tcl: fix Phase 7d oo tests using ::name-with-hyphens

Tcl tokenizer treats $::g-name as $::g + literal -name, so the var
lookup fails. Renamed test vars to ::gname / ::nval (no hyphens).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

hosts/javascript/platform.py

@@ -2771,8 +2771,8 @@ PLATFORM_DOM_JS = """
     // If lambda takes 0 params, call without event arg (convenience for on-click handlers)
     var wrapped = isLambda(handler)
       ? (lambdaParams(handler).length === 0
-        ? function(e) { try { cekCall(handler, NIL); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } }
-        : function(e) { try { cekCall(handler, [e]); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } })
+        ? function(e) { try { var r = cekCall(handler, NIL); if (globalThis._driveAsync) globalThis._driveAsync(r); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } }
+        : function(e) { try { var r = cekCall(handler, [e]); if (globalThis._driveAsync) globalThis._driveAsync(r); } catch(err) { console.error("[sx-ref] domListen handler error:", name, err); } })
       : handler;
     if (name === "click") logInfo("domListen: click on <" + (el.tagName||"?").toLowerCase() + "> text=" + (el.textContent||"").substring(0,20) + " isLambda=" + isLambda(handler));
     var passiveEvents = { touchstart: 1, touchmove: 1, wheel: 1, scroll: 1 };

hosts/ocaml/bin/mcp_tree.ml

@@ -1892,8 +1892,34 @@ let handle_sx_harness_eval args =
     let file = args |> member "file" |> to_string_option in
     let setup_str = args |> member "setup" |> to_string_option in
     let files_json = try args |> member "files" with _ -> `Null in
+    let host_stubs = match args |> member "host_stubs" with `Bool b -> b | _ -> false in
     let e = !env in
     let warnings = ref [] in
+    (* Inject stub host primitives so files using host-get/host-new/etc. can load *)
+    if host_stubs then begin
+      let stubs = {|
+        (define host-global (fn (&rest _) nil))
+        (define host-get (fn (&rest _) nil))
+        (define host-set! (fn (obj k v) v))
+        (define host-call (fn (&rest _) nil))
+        (define host-new (fn (&rest _) (dict)))
+        (define host-callback (fn (f) f))
+        (define host-typeof (fn (&rest _) "string"))
+        (define hs-ref-eq (fn (a b) (identical? a b)))
+        (define host-call-fn (fn (&rest _) nil))
+        (define host-iter? (fn (&rest _) false))
+        (define host-to-list (fn (&rest _) (list)))
+        (define host-await (fn (&rest _) nil))
+        (define host-new-function (fn (&rest _) nil))
+        (define load-library! (fn (&rest _) false))
+      |} in
+      let stub_exprs = Sx_parser.parse_all stubs in
+      List.iter (fun expr ->
+        try ignore (Sx_ref.eval_expr expr (Env e))
+        with exn ->
+          warnings := Printf.sprintf "Stub warning: %s" (Printexc.to_string exn) :: !warnings
+      ) stub_exprs
+    end;
     (* Collect all files to load *)
     let all_files = match files_json with
       | `List items ->
@@ -3018,7 +3044,8 @@ let tool_definitions = `List [
      ("mock", `Assoc [("type", `String "string"); ("description", `String "Optional mock platform overrides as SX dict, e.g. {:fetch (fn (url) {:status 200})}")]);
      ("file", `Assoc [("type", `String "string"); ("description", `String "Optional .sx file to load for definitions")]);
      ("files", `Assoc [("type", `String "array"); ("items", `Assoc [("type", `String "string")]); ("description", `String "Multiple .sx files to load in order")]);
-     ("setup", `Assoc [("type", `String "string"); ("description", `String "SX setup expression to run before main evaluation")])]
+     ("setup", `Assoc [("type", `String "string"); ("description", `String "SX setup expression to run before main evaluation")]);
+     ("host_stubs", `Assoc [("type", `String "boolean"); ("description", `String "If true, inject nil-returning stubs for host-get/host-set!/host-call/host-new/etc. so files that use host primitives can load in the harness")])]
     ["expr"];
   tool "sx_nav" "Manage sx-docs navigation and articles. Modes: list (all nav items with status), check (validate consistency), add (create article + nav entry), delete (remove nav entry + page fn), move (move entry between sections, rewriting hrefs)."
     [("mode", `Assoc [("type", `String "string"); ("description", `String "Mode: list, check, add, delete, or move")]);

hosts/ocaml/bin/sx_server.ml

@@ -703,6 +703,11 @@ let setup_evaluator_bridge env =
     | [expr; e] -> Sx_ref.eval_expr expr (Env (Sx_runtime.unwrap_env e))
     | [expr] -> Sx_ref.eval_expr expr (Env env)
     | _ -> raise (Eval_error "eval-expr: expected (expr env?)"));
+  (* eval-in-env: (env expr) → result.  Evaluates expr in the given env. *)
+  Sx_primitives.register "eval-in-env" (fun args ->
+    match args with
+    | [e; expr] -> Sx_ref.eval_expr expr e
+    | _ -> raise (Eval_error "eval-in-env: (env expr)"));
   bind "trampoline" (fun args ->
     match args with
     | [v] ->
@@ -764,7 +769,13 @@ let setup_evaluator_bridge env =
     | _ -> raise (Eval_error "register-special-form!: expected (name handler)"));
   ignore (env_bind env "*custom-special-forms*" Sx_ref.custom_special_forms);
   ignore (Sx_ref.register_special_form (String "<>") (NativeFn ("<>", fun args ->
-    List (List.map (fun a -> Sx_ref.eval_expr a (Env env)) args))))
+    List (List.map (fun a -> Sx_ref.eval_expr a (Env env)) args))));
+  (* current-env: special form — returns current lexical env as a first-class value *)
+  ignore (Sx_ref.register_special_form (String "current-env")
+    (NativeFn ("current-env", fun args ->
+      match args with
+      | [_arg_list; env_val] -> env_val
+      | _ -> Nil)))
 
 (* ---- Type predicates and introspection ---- *)
 let setup_introspection env =
@@ -950,7 +961,24 @@ let setup_env_operations env =
   bind "env-has?" (fun args -> match args with [e; String k] -> Bool (Sx_types.env_has (uw e) k) | [e; Keyword k] -> Bool (Sx_types.env_has (uw e) k) | _ -> raise (Eval_error "env-has?: expected env and string"));
   bind "env-bind!" (fun args -> match args with [e; String k; v] -> Sx_types.env_bind (uw e) k v | [e; Keyword k; v] -> Sx_types.env_bind (uw e) k v | _ -> raise (Eval_error "env-bind!: expected env, key, value"));
   bind "env-set!" (fun args -> match args with [e; String k; v] -> Sx_types.env_set (uw e) k v | [e; Keyword k; v] -> Sx_types.env_set (uw e) k v | _ -> raise (Eval_error "env-set!: expected env, key, value"));
-  bind "env-extend" (fun args -> match args with [e] -> Env (Sx_types.env_extend (uw e)) | _ -> raise (Eval_error "env-extend: expected env"));
+  bind "env-extend" (fun args ->
+    match args with
+    | e :: pairs ->
+      let child = Sx_types.env_extend (uw e) in
+      let rec go = function
+        | [] -> ()
+        | k :: v :: rest ->
+          ignore (Sx_types.env_bind child (Sx_runtime.value_to_str k) v); go rest
+        | [_] -> raise (Eval_error "env-extend: odd number of key-val pairs") in
+      go pairs; Env child
+    | _ -> raise (Eval_error "env-extend: expected env"));
+  bind "env-lookup" (fun args ->
+    match args with
+    | [e; key] ->
+      let k = Sx_runtime.value_to_str key in
+      let raw = uw e in
+      if Sx_types.env_has raw k then Sx_types.env_get raw k else Nil
+    | _ -> raise (Eval_error "env-lookup: (env key)"));
   bind "env-merge" (fun args -> match args with [a; b] -> Sx_runtime.env_merge a b | _ -> raise (Eval_error "env-merge: expected 2 envs"))
 
 (* ---- Strict mode (gradual type system support) ---- *)

hosts/ocaml/lib/dune

@@ -1,4 +1,4 @@
 (library
  (name sx)
  (wrapped false)
- (libraries re re.pcre))
+ (libraries re re.pcre unix))

hosts/ocaml/lib/sx_runtime.ml

@@ -539,3 +539,4 @@ let jit_try_call f args =
       (match hook f arg_list with Some result -> incr _jit_hit; result | None -> incr _jit_miss; _jit_skip_sentinel)
     | _ -> incr _jit_skip; _jit_skip_sentinel
 
+

lib/common-lisp/tests/runtime.sx

@@ -0,0 +1,207 @@
+;; lib/common-lisp/tests/runtime.sx — tests for CL runtime layer
+
+(load "lib/common-lisp/runtime.sx")
+
+(defsuite
+  "cl-types"
+  (deftest "cl-null? nil" (assert= true (cl-null? nil)))
+  (deftest "cl-null? false" (assert= false (cl-null? false)))
+  (deftest
+    "cl-consp? pair"
+    (assert= true (cl-consp? (list 1 2))))
+  (deftest "cl-consp? nil" (assert= false (cl-consp? nil)))
+  (deftest "cl-listp? nil" (assert= true (cl-listp? nil)))
+  (deftest
+    "cl-listp? list"
+    (assert= true (cl-listp? (list 1 2))))
+  (deftest "cl-atom? nil" (assert= true (cl-atom? nil)))
+  (deftest "cl-atom? pair" (assert= false (cl-atom? (list 1))))
+  (deftest "cl-integerp?" (assert= true (cl-integerp? 42)))
+  (deftest "cl-floatp?" (assert= true (cl-floatp? 3.14)))
+  (deftest
+    "cl-characterp?"
+    (assert= true (cl-characterp? (integer->char 65))))
+  (deftest "cl-stringp?" (assert= true (cl-stringp? "hello")))
+  (deftest "cl-symbolp?" (assert= true (cl-symbolp? (quote foo)))))
+
+(defsuite
+  "cl-arithmetic"
+  (deftest "cl-mod" (assert= 1 (cl-mod 10 3)))
+  (deftest "cl-rem" (assert= 1 (cl-rem 10 3)))
+  (deftest
+    "cl-quotient"
+    (assert= 3 (cl-quotient 10 3)))
+  (deftest "cl-gcd" (assert= 4 (cl-gcd 12 8)))
+  (deftest "cl-lcm" (assert= 12 (cl-lcm 4 6)))
+  (deftest "cl-abs pos" (assert= 5 (cl-abs 5)))
+  (deftest "cl-abs neg" (assert= 5 (cl-abs -5)))
+  (deftest "cl-min" (assert= 2 (cl-min 2 7)))
+  (deftest "cl-max" (assert= 7 (cl-max 2 7)))
+  (deftest "cl-evenp? t" (assert= true (cl-evenp? 4)))
+  (deftest "cl-evenp? f" (assert= false (cl-evenp? 3)))
+  (deftest "cl-oddp? t" (assert= true (cl-oddp? 7)))
+  (deftest "cl-zerop?" (assert= true (cl-zerop? 0)))
+  (deftest "cl-plusp?" (assert= true (cl-plusp? 1)))
+  (deftest "cl-minusp?" (assert= true (cl-minusp? -1)))
+  (deftest "cl-signum pos" (assert= 1 (cl-signum 42)))
+  (deftest "cl-signum neg" (assert= -1 (cl-signum -7)))
+  (deftest "cl-signum zero" (assert= 0 (cl-signum 0))))
+
+(defsuite
+  "cl-chars"
+  (deftest
+    "cl-char-code"
+    (assert= 65 (cl-char-code (integer->char 65))))
+  (deftest "cl-code-char" (assert= true (char? (cl-code-char 65))))
+  (deftest
+    "cl-char-upcase"
+    (assert=
+      (integer->char 65)
+      (cl-char-upcase (integer->char 97))))
+  (deftest
+    "cl-char-downcase"
+    (assert=
+      (integer->char 97)
+      (cl-char-downcase (integer->char 65))))
+  (deftest
+    "cl-alpha-char-p"
+    (assert= true (cl-alpha-char-p (integer->char 65))))
+  (deftest
+    "cl-digit-char-p"
+    (assert= true (cl-digit-char-p (integer->char 48))))
+  (deftest
+    "cl-char=?"
+    (assert=
+      true
+      (cl-char=? (integer->char 65) (integer->char 65))))
+  (deftest
+    "cl-char<?"
+    (assert=
+      true
+      (cl-char<? (integer->char 65) (integer->char 90))))
+  (deftest
+    "cl-char space"
+    (assert= (integer->char 32) cl-char-space))
+  (deftest
+    "cl-char newline"
+    (assert= (integer->char 10) cl-char-newline)))
+
+(defsuite
+  "cl-format"
+  (deftest
+    "cl-format nil basic"
+    (assert= "hello" (cl-format nil "~a" "hello")))
+  (deftest
+    "cl-format nil number"
+    (assert= "42" (cl-format nil "~d" 42)))
+  (deftest
+    "cl-format nil hex"
+    (assert= "ff" (cl-format nil "~x" 255)))
+  (deftest
+    "cl-format nil template"
+    (assert= "x=3 y=4" (cl-format nil "x=~d y=~d" 3 4)))
+  (deftest "cl-format nil tilde" (assert= "a~b" (cl-format nil "a~~b"))))
+
+(defsuite
+  "cl-gensym"
+  (deftest
+    "cl-gensym returns symbol"
+    (assert= "symbol" (type-of (cl-gensym))))
+  (deftest "cl-gensym unique" (assert= false (= (cl-gensym) (cl-gensym)))))
+
+(defsuite
+  "cl-sets"
+  (deftest "cl-make-set empty" (assert= true (cl-set? (cl-make-set))))
+  (deftest
+    "cl-set-add/member"
+    (let
+      ((s (cl-make-set)))
+      (do
+        (cl-set-add s 1)
+        (assert= true (cl-set-memberp s 1)))))
+  (deftest
+    "cl-set-memberp false"
+    (assert= false (cl-set-memberp (cl-make-set) 42)))
+  (deftest
+    "cl-list->set"
+    (let
+      ((s (cl-list->set (list 1 2 3))))
+      (assert= true (cl-set-memberp s 2)))))
+
+(defsuite
+  "cl-lists"
+  (deftest
+    "cl-nth 0"
+    (assert=
+      1
+      (cl-nth 0 (list 1 2 3))))
+  (deftest
+    "cl-nth 2"
+    (assert=
+      3
+      (cl-nth 2 (list 1 2 3))))
+  (deftest
+    "cl-last"
+    (assert=
+      (list 3)
+      (cl-last (list 1 2 3))))
+  (deftest
+    "cl-butlast"
+    (assert=
+      (list 1 2)
+      (cl-butlast (list 1 2 3))))
+  (deftest
+    "cl-nthcdr 1"
+    (assert=
+      (list 2 3)
+      (cl-nthcdr 1 (list 1 2 3))))
+  (deftest
+    "cl-assoc hit"
+    (assert=
+      (list "b" 2)
+      (cl-assoc "b" (list (list "a" 1) (list "b" 2)))))
+  (deftest
+    "cl-assoc miss"
+    (assert= nil (cl-assoc "z" (list (list "a" 1)))))
+  (deftest
+    "cl-getf hit"
+    (assert= 42 (cl-getf (list "x" 42 "y" 99) "x")))
+  (deftest "cl-getf miss" (assert= nil (cl-getf (list "x" 42) "z")))
+  (deftest
+    "cl-adjoin new"
+    (assert=
+      (list 0 1 2)
+      (cl-adjoin 0 (list 1 2))))
+  (deftest
+    "cl-adjoin dup"
+    (assert=
+      (list 1 2)
+      (cl-adjoin 1 (list 1 2))))
+  (deftest
+    "cl-flatten"
+    (assert=
+      (list 1 2 3 4)
+      (cl-flatten (list 1 (list 2 3) 4))))
+  (deftest
+    "cl-member hit"
+    (assert=
+      (list 2 3)
+      (cl-member 2 (list 1 2 3))))
+  (deftest
+    "cl-member miss"
+    (assert=
+      nil
+      (cl-member 9 (list 1 2 3)))))
+
+(defsuite
+  "cl-radix"
+  (deftest "binary" (assert= "1010" (cl-format-binary 10)))
+  (deftest "octal" (assert= "17" (cl-format-octal 15)))
+  (deftest "hex" (assert= "ff" (cl-format-hex 255)))
+  (deftest "decimal" (assert= "42" (cl-format-decimal 42)))
+  (deftest
+    "n->s r16"
+    (assert= "1f" (cl-integer-to-string 31 16)))
+  (deftest
+    "s->n r16"
+    (assert= 31 (cl-string-to-integer "1f" 16))))

lib/fiber.sx

@@ -0,0 +1,44 @@
+; lib/fiber.sx — pure SX fiber library using call/cc
+;
+; A fiber is a cooperative coroutine with true suspension (no eager
+; pre-execution). Each fiber is a dict {:resume fn :done? fn}.
+;
+; make-fiber body   → fiber dict
+;   body = (fn (yield init-val) ...)  — body receives yield + first resume val
+;   yield = (fn (val) ...)            — suspends fiber, returns val to resumer
+;
+; fiber-resume f v  → next yielded value, or nil when body returns
+; fiber-done? f     → true after body has returned
+
+(define make-fiber
+  (fn (body)
+    (let
+      ((resume-k nil)
+        (caller-k nil)
+        (done false))
+      (let
+        ((yield
+            (fn (val)
+              (call/cc
+                (fn (k)
+                  (set! resume-k k)
+                  (caller-k val))))))
+        {:resume
+         (fn (val)
+           (if
+             done
+             nil
+             (call/cc
+               (fn (k)
+                 (set! caller-k k)
+                 (if
+                   (nil? resume-k)
+                   (begin
+                     (body yield val)
+                     (set! done true)
+                     (k nil))
+                   (resume-k val))))))
+         :done? (fn () done)}))))
+
+(define fiber-resume (fn (f v) ((get f :resume) v)))
+(define fiber-done?  (fn (f) ((get f :done?))))

lib/haskell/conformance.sh

@@ -0,0 +1,140 @@
+#!/usr/bin/env bash
+# lib/haskell/conformance.sh — run the classic-program test suites.
+# Writes lib/haskell/scoreboard.json and lib/haskell/scoreboard.md.
+#
+# Usage:
+#   bash lib/haskell/conformance.sh           # run + write scoreboards
+#   bash lib/haskell/conformance.sh --check   # run only, exit 1 on failure
+
+set -euo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="hosts/ocaml/_build/default/bin/sx_server.exe"
+if [ ! -x "$SX_SERVER" ]; then
+  MAIN_ROOT=$(git worktree list | head -1 | awk '{print $1}')
+  if [ -x "$MAIN_ROOT/$SX_SERVER" ]; then
+    SX_SERVER="$MAIN_ROOT/$SX_SERVER"
+  else
+    echo "ERROR: sx_server.exe not found. Run: cd hosts/ocaml && dune build"
+    exit 1
+  fi
+fi
+
+PROGRAMS=(fib sieve quicksort nqueens calculator collatz palindrome maybe fizzbuzz anagram roman binary either primes zipwith matrix wordcount powers)
+PASS_COUNTS=()
+FAIL_COUNTS=()
+
+run_suite() {
+  local prog="$1"
+  local FILE="lib/haskell/tests/program-${prog}.sx"
+  local TMPFILE
+  TMPFILE=$(mktemp)
+  cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/haskell/tokenizer.sx")
+(load "lib/haskell/layout.sx")
+(load "lib/haskell/parser.sx")
+(load "lib/haskell/desugar.sx")
+(load "lib/haskell/runtime.sx")
+(load "lib/haskell/match.sx")
+(load "lib/haskell/eval.sx")
+(load "lib/haskell/testlib.sx")
+(epoch 2)
+(load "$FILE")
+(epoch 3)
+(eval "(list hk-test-pass hk-test-fail)")
+EPOCHS
+  local OUTPUT
+  OUTPUT=$(timeout 120 "$SX_SERVER" < "$TMPFILE" 2>&1 || true)
+  rm -f "$TMPFILE"
+
+  local LINE
+  LINE=$(echo "$OUTPUT" | awk '/^\(ok-len 3 / {getline; print; exit}')
+  if [ -z "$LINE" ]; then
+    LINE=$(echo "$OUTPUT" | grep -E '^\(ok 3 \([0-9]+ [0-9]+\)\)' | tail -1 \
+           | sed -E 's/^\(ok 3 //; s/\)$//' || true)
+  fi
+  if [ -z "$LINE" ]; then
+    echo "0 1"
+  else
+    local P F
+    P=$(echo "$LINE" | sed -E 's/^\(([0-9]+) ([0-9]+)\).*/\1/' || echo "0")
+    F=$(echo "$LINE" | sed -E 's/^\(([0-9]+) ([0-9]+)\).*/\2/' || echo "1")
+    echo "$P $F"
+  fi
+}
+
+for prog in "${PROGRAMS[@]}"; do
+  RESULT=$(run_suite "$prog")
+  P=$(echo "$RESULT" | cut -d' ' -f1)
+  F=$(echo "$RESULT" | cut -d' ' -f2)
+  PASS_COUNTS+=("$P")
+  FAIL_COUNTS+=("$F")
+  T=$((P + F))
+  if [ "$F" -eq 0 ]; then
+    printf '✓ %-14s  %d/%d\n' "${prog}.hs" "$P" "$T"
+  else
+    printf '✗ %-14s  %d/%d\n' "${prog}.hs" "$P" "$T"
+  fi
+done
+
+TOTAL_PASS=0
+TOTAL_FAIL=0
+PROG_PASS=0
+for i in "${!PROGRAMS[@]}"; do
+  TOTAL_PASS=$((TOTAL_PASS + PASS_COUNTS[i]))
+  TOTAL_FAIL=$((TOTAL_FAIL + FAIL_COUNTS[i]))
+  [ "${FAIL_COUNTS[$i]}" -eq 0 ] && PROG_PASS=$((PROG_PASS + 1))
+done
+PROG_TOTAL=${#PROGRAMS[@]}
+
+echo ""
+echo "Classic programs: ${TOTAL_PASS}/$((TOTAL_PASS + TOTAL_FAIL)) tests  |  ${PROG_PASS}/${PROG_TOTAL} programs passing"
+
+if [[ "${1:-}" == "--check" ]]; then
+  [ $TOTAL_FAIL -eq 0 ]
+  exit $?
+fi
+
+DATE=$(date '+%Y-%m-%d')
+
+# scoreboard.json
+{
+  printf '{\n'
+  printf '  "date": "%s",\n' "$DATE"
+  printf '  "total_pass": %d,\n' "$TOTAL_PASS"
+  printf '  "total_fail": %d,\n' "$TOTAL_FAIL"
+  printf '  "programs": {\n'
+  last=$((${#PROGRAMS[@]} - 1))
+  for i in "${!PROGRAMS[@]}"; do
+    prog="${PROGRAMS[$i]}"
+    if [ $i -lt $last ]; then
+      printf '    "%s": {"pass": %d, "fail": %d},\n' "$prog" "${PASS_COUNTS[$i]}" "${FAIL_COUNTS[$i]}"
+    else
+      printf '    "%s": {"pass": %d, "fail": %d}\n'  "$prog" "${PASS_COUNTS[$i]}" "${FAIL_COUNTS[$i]}"
+    fi
+  done
+  printf '  }\n'
+  printf '}\n'
+} > lib/haskell/scoreboard.json
+
+# scoreboard.md
+{
+  printf '# Haskell-on-SX Scoreboard\n\n'
+  printf 'Updated %s · Phase 6 (prelude extras + 18 programs)\n\n' "$DATE"
+  printf '| Program | Tests | Status |\n'
+  printf '|---------|-------|--------|\n'
+  for i in "${!PROGRAMS[@]}"; do
+    prog="${PROGRAMS[$i]}"
+    P=${PASS_COUNTS[$i]}
+    F=${FAIL_COUNTS[$i]}
+    T=$((P + F))
+    [ "$F" -eq 0 ] && STATUS="✓" || STATUS="✗"
+    printf '| %s | %d/%d | %s |\n' "${prog}.hs" "$P" "$T" "$STATUS"
+  done
+  printf '| **Total** | **%d/%d** | **%d/%d programs** |\n' \
+    "$TOTAL_PASS" "$((TOTAL_PASS + TOTAL_FAIL))" "$PROG_PASS" "$PROG_TOTAL"
+} > lib/haskell/scoreboard.md
+
+echo "Wrote lib/haskell/scoreboard.json and lib/haskell/scoreboard.md"
+[ $TOTAL_FAIL -eq 0 ]

lib/haskell/desugar.sx

@@ -0,0 +1,249 @@
+;; Desugar the Haskell surface AST into a smaller core AST.
+;;
+;; Eliminates the three surface-only shapes produced by the parser:
+;;   :where BODY DECLS     →  :let DECLS BODY
+;;   :guarded GUARDS       →  :if C1 E1 (:if C2 E2 … (:app error …))
+;;   :list-comp EXPR QUALS →  concatMap-based expression (§3.11)
+;;
+;; Everything else (:app, :op, :lambda, :let, :case, :do, :tuple,
+;; :list, :range, :if, :neg, :sect-left / :sect-right, plus all
+;; leaf forms and pattern / type nodes) is passed through after
+;; recursing into children.
+
+(define
+  hk-guards-to-if
+  (fn
+    (guards)
+    (cond
+      ((empty? guards)
+        (list
+          :app
+          (list :var "error")
+          (list :string "Non-exhaustive guards")))
+      (:else
+        (let
+          ((g (first guards)))
+          (list
+            :if
+            (hk-desugar (nth g 1))
+            (hk-desugar (nth g 2))
+            (hk-guards-to-if (rest guards))))))))
+
+;; do-notation desugaring (Haskell 98 §3.14):
+;;   do { e }              =  e
+;;   do { e ; ss }         =  e >> do { ss }
+;;   do { p <- e ; ss }    =  e >>= \p -> do { ss }
+;;   do { let decls ; ss } =  let decls in do { ss }
+(define
+  hk-desugar-do
+  (fn
+    (stmts)
+    (cond
+      ((empty? stmts) (raise "empty do block"))
+      ((empty? (rest stmts))
+        (let ((s (first stmts)))
+          (cond
+            ((= (first s) "do-expr") (hk-desugar (nth s 1)))
+            (:else
+              (raise "do block must end with an expression")))))
+      (:else
+        (let
+          ((s (first stmts)) (rest-stmts (rest stmts)))
+          (let
+            ((rest-do (hk-desugar-do rest-stmts)))
+            (cond
+              ((= (first s) "do-expr")
+                (list
+                  :app
+                  (list
+                    :app
+                    (list :var ">>")
+                    (hk-desugar (nth s 1)))
+                  rest-do))
+              ((= (first s) "do-bind")
+                (list
+                  :app
+                  (list
+                    :app
+                    (list :var ">>=")
+                    (hk-desugar (nth s 2)))
+                  (list :lambda (list (nth s 1)) rest-do)))
+              ((= (first s) "do-let")
+                (list
+                  :let
+                  (map hk-desugar (nth s 1))
+                  rest-do))
+              (:else (raise "unknown do-stmt tag")))))))))
+
+;; List-comprehension desugaring (Haskell 98 §3.11):
+;;   [e |             ]  =  [e]
+;;   [e | b,     Q    ]  =  if b then [e | Q] else []
+;;   [e | p <- l, Q    ]  =  concatMap (\p -> [e | Q]) l
+;;   [e | let ds, Q    ]  =  let ds in [e | Q]
+(define
+  hk-lc-desugar
+  (fn
+    (e quals)
+    (cond
+      ((empty? quals) (list :list (list e)))
+      (:else
+        (let
+          ((q (first quals)))
+          (let
+            ((qtag (first q)))
+            (cond
+              ((= qtag "q-guard")
+                (list
+                  :if
+                  (hk-desugar (nth q 1))
+                  (hk-lc-desugar e (rest quals))
+                  (list :list (list))))
+              ((= qtag "q-gen")
+                (list
+                  :app
+                  (list
+                    :app
+                    (list :var "concatMap")
+                    (list
+                      :lambda
+                      (list (nth q 1))
+                      (hk-lc-desugar e (rest quals))))
+                  (hk-desugar (nth q 2))))
+              ((= qtag "q-let")
+                (list
+                  :let
+                  (map hk-desugar (nth q 1))
+                  (hk-lc-desugar e (rest quals))))
+              (:else
+                (raise
+                  (str
+                    "hk-lc-desugar: unknown qualifier tag "
+                    qtag))))))))))
+
+(define
+  hk-desugar
+  (fn
+    (node)
+    (cond
+      ((not (list? node)) node)
+      ((empty? node) node)
+      (:else
+        (let
+          ((tag (first node)))
+          (cond
+            ;; Transformations
+            ((= tag "where")
+              (list
+                :let
+                (map hk-desugar (nth node 2))
+                (hk-desugar (nth node 1))))
+            ((= tag "guarded") (hk-guards-to-if (nth node 1)))
+            ((= tag "list-comp")
+              (hk-lc-desugar
+                (hk-desugar (nth node 1))
+                (nth node 2)))
+
+            ;; Expression nodes
+            ((= tag "app")
+              (list
+                :app
+                (hk-desugar (nth node 1))
+                (hk-desugar (nth node 2))))
+            ((= tag "op")
+              (list
+                :op
+                (nth node 1)
+                (hk-desugar (nth node 2))
+                (hk-desugar (nth node 3))))
+            ((= tag "neg") (list :neg (hk-desugar (nth node 1))))
+            ((= tag "if")
+              (list
+                :if
+                (hk-desugar (nth node 1))
+                (hk-desugar (nth node 2))
+                (hk-desugar (nth node 3))))
+            ((= tag "tuple")
+              (list :tuple (map hk-desugar (nth node 1))))
+            ((= tag "list")
+              (list :list (map hk-desugar (nth node 1))))
+            ((= tag "range")
+              (list
+                :range
+                (hk-desugar (nth node 1))
+                (hk-desugar (nth node 2))))
+            ((= tag "range-step")
+              (list
+                :range-step
+                (hk-desugar (nth node 1))
+                (hk-desugar (nth node 2))
+                (hk-desugar (nth node 3))))
+            ((= tag "lambda")
+              (list
+                :lambda
+                (nth node 1)
+                (hk-desugar (nth node 2))))
+            ((= tag "let")
+              (list
+                :let
+                (map hk-desugar (nth node 1))
+                (hk-desugar (nth node 2))))
+            ((= tag "case")
+              (list
+                :case
+                (hk-desugar (nth node 1))
+                (map hk-desugar (nth node 2))))
+            ((= tag "alt")
+              (list :alt (nth node 1) (hk-desugar (nth node 2))))
+            ((= tag "do") (hk-desugar-do (nth node 1)))
+            ((= tag "sect-left")
+              (list
+                :sect-left
+                (nth node 1)
+                (hk-desugar (nth node 2))))
+            ((= tag "sect-right")
+              (list
+                :sect-right
+                (nth node 1)
+                (hk-desugar (nth node 2))))
+
+            ;; Top-level
+            ((= tag "program")
+              (list :program (map hk-desugar (nth node 1))))
+            ((= tag "module")
+              (list
+                :module
+                (nth node 1)
+                (nth node 2)
+                (nth node 3)
+                (map hk-desugar (nth node 4))))
+
+            ;; Decls carrying a body
+            ((= tag "fun-clause")
+              (list
+                :fun-clause
+                (nth node 1)
+                (nth node 2)
+                (hk-desugar (nth node 3))))
+            ((= tag "pat-bind")
+              (list
+                :pat-bind
+                (nth node 1)
+                (hk-desugar (nth node 2))))
+            ((= tag "bind")
+              (list
+                :bind
+                (nth node 1)
+                (hk-desugar (nth node 2))))
+
+            ;; Everything else: leaf literals, vars, cons, patterns,
+            ;; types, imports, type-sigs, data / newtype / fixity, …
+            (:else node)))))))
+
+;; Convenience — tokenize + layout + parse + desugar.
+(define
+  hk-core
+  (fn (src) (hk-desugar (hk-parse-top src))))
+
+(define
+  hk-core-expr
+  (fn (src) (hk-desugar (hk-parse src))))

lib/haskell/infer.sx

@@ -0,0 +1,658 @@
+;; infer.sx — Hindley-Milner Algorithm W for Haskell-on-SX (Phase 4).
+;;
+;; Types: TVar, TCon, TArr, TApp, TTuple, TScheme
+;; Substitution: apply, compose, restrict
+;; Unification (with occurs check)
+;; Instantiation + generalization (let-polymorphism)
+;; Algorithm W for: literals, var, con, lambda, app, let, if, op, tuple, list
+
+;; ─── Type constructors ────────────────────────────────────────────────────────
+
+(define hk-tvar (fn (n) (list "TVar" n)))
+(define hk-tcon (fn (s) (list "TCon" s)))
+(define hk-tarr (fn (a b) (list "TArr" a b)))
+(define hk-tapp (fn (a b) (list "TApp" a b)))
+(define hk-ttuple (fn (ts) (list "TTuple" ts)))
+(define hk-tscheme (fn (vs t) (list "TScheme" vs t)))
+
+(define hk-tvar? (fn (t) (and (list? t) (not (empty? t)) (= (first t) "TVar"))))
+(define hk-tcon? (fn (t) (and (list? t) (not (empty? t)) (= (first t) "TCon"))))
+(define hk-tarr? (fn (t) (and (list? t) (not (empty? t)) (= (first t) "TArr"))))
+(define hk-tapp? (fn (t) (and (list? t) (not (empty? t)) (= (first t) "TApp"))))
+(define hk-ttuple? (fn (t) (and (list? t) (not (empty? t)) (= (first t) "TTuple"))))
+(define hk-tscheme? (fn (t) (and (list? t) (not (empty? t)) (= (first t) "TScheme"))))
+
+(define hk-tvar-name (fn (t) (nth t 1)))
+(define hk-tcon-name (fn (t) (nth t 1)))
+(define hk-tarr-t1 (fn (t) (nth t 1)))
+(define hk-tarr-t2 (fn (t) (nth t 2)))
+(define hk-tapp-t1 (fn (t) (nth t 1)))
+(define hk-tapp-t2 (fn (t) (nth t 2)))
+(define hk-ttuple-ts (fn (t) (nth t 1)))
+(define hk-tscheme-vs (fn (t) (nth t 1)))
+(define hk-tscheme-type (fn (t) (nth t 2)))
+
+(define hk-t-int    (hk-tcon "Int"))
+(define hk-t-bool   (hk-tcon "Bool"))
+(define hk-t-string (hk-tcon "String"))
+(define hk-t-char   (hk-tcon "Char"))
+(define hk-t-float  (hk-tcon "Float"))
+(define hk-t-list (fn (t) (hk-tapp (hk-tcon "[]") t)))
+
+;; ─── Type formatter ──────────────────────────────────────────────────────────
+
+(define
+  hk-type->str
+  (fn
+    (t)
+    (cond
+      ((hk-tvar? t)   (hk-tvar-name t))
+      ((hk-tcon? t)   (hk-tcon-name t))
+      ((hk-tarr? t)
+       (let ((s1 (if (hk-tarr? (hk-tarr-t1 t))
+                   (str "(" (hk-type->str (hk-tarr-t1 t)) ")")
+                   (hk-type->str (hk-tarr-t1 t)))))
+         (str s1 " -> " (hk-type->str (hk-tarr-t2 t)))))
+      ((hk-tapp? t)
+       (let ((h (hk-tapp-t1 t)))
+         (cond
+           ((and (hk-tcon? h) (= (hk-tcon-name h) "[]"))
+            (str "[" (hk-type->str (hk-tapp-t2 t)) "]"))
+           (:else
+            (str "(" (hk-type->str h) " " (hk-type->str (hk-tapp-t2 t)) ")")))))
+      ((hk-ttuple? t)
+       (str "(" (join ", " (map hk-type->str (hk-ttuple-ts t))) ")"))
+      ((hk-tscheme? t)
+       (str "forall " (join " " (hk-tscheme-vs t)) ". " (hk-type->str (hk-tscheme-type t))))
+      (:else "<?>"))))
+
+;; ─── Fresh variable counter ───────────────────────────────────────────────────
+
+(define hk-fresh-ctr 0)
+(define hk-fresh (fn () (set! hk-fresh-ctr (+ hk-fresh-ctr 1)) (hk-tvar (str "t" hk-fresh-ctr))))
+(define hk-reset-fresh (fn () (set! hk-fresh-ctr 0)))
+
+;; ─── Utilities ───────────────────────────────────────────────────────────────
+
+(define hk-infer-member? (fn (x lst) (some (fn (y) (= x y)) lst)))
+
+(define
+  hk-nub
+  (fn (lst)
+    (reduce (fn (acc x) (if (hk-infer-member? x acc) acc (append acc (list x)))) (list) lst)))
+
+;; ─── Free type variables ──────────────────────────────────────────────────────
+
+(define
+  hk-ftv
+  (fn
+    (t)
+    (cond
+      ((hk-tvar? t)    (list (hk-tvar-name t)))
+      ((hk-tcon? t)    (list))
+      ((hk-tarr? t)    (append (hk-ftv (hk-tarr-t1 t)) (hk-ftv (hk-tarr-t2 t))))
+      ((hk-tapp? t)    (append (hk-ftv (hk-tapp-t1 t)) (hk-ftv (hk-tapp-t2 t))))
+      ((hk-ttuple? t)  (reduce append (list) (map hk-ftv (hk-ttuple-ts t))))
+      ((hk-tscheme? t)
+       (filter
+         (fn (v) (not (hk-infer-member? v (hk-tscheme-vs t))))
+         (hk-ftv (hk-tscheme-type t))))
+      (:else (list)))))
+
+(define
+  hk-ftv-env
+  (fn (env)
+    (reduce (fn (acc k) (append acc (hk-ftv (get env k)))) (list) (keys env))))
+
+;; ─── Substitution ─────────────────────────────────────────────────────────────
+
+(define hk-subst-empty (dict))
+
+(define
+  hk-subst-restrict
+  (fn
+    (s exclude)
+    (let ((r (dict)))
+      (for-each
+        (fn (k)
+          (when (not (hk-infer-member? k exclude))
+            (dict-set! r k (get s k))))
+        (keys s))
+      r)))
+
+(define
+  hk-subst-apply
+  (fn
+    (s t)
+    (cond
+      ((hk-tvar? t)
+       (let ((v (get s (hk-tvar-name t))))
+         (if (nil? v) t (hk-subst-apply s v))))
+      ((hk-tarr? t)
+       (hk-tarr (hk-subst-apply s (hk-tarr-t1 t))
+                (hk-subst-apply s (hk-tarr-t2 t))))
+      ((hk-tapp? t)
+       (hk-tapp (hk-subst-apply s (hk-tapp-t1 t))
+                (hk-subst-apply s (hk-tapp-t2 t))))
+      ((hk-ttuple? t)
+       (hk-ttuple (map (fn (u) (hk-subst-apply s u)) (hk-ttuple-ts t))))
+      ((hk-tscheme? t)
+       (let ((s2 (hk-subst-restrict s (hk-tscheme-vs t))))
+         (hk-tscheme (hk-tscheme-vs t)
+                     (hk-subst-apply s2 (hk-tscheme-type t)))))
+      (:else t))))
+
+(define
+  hk-subst-compose
+  (fn
+    (s2 s1)
+    (let ((r (hk-dict-copy s2)))
+      (for-each
+        (fn (k)
+          (when (nil? (get r k))
+            (dict-set! r k (hk-subst-apply s2 (get s1 k)))))
+        (keys s1))
+      r)))
+
+(define
+  hk-env-apply-subst
+  (fn
+    (s env)
+    (let ((r (dict)))
+      (for-each (fn (k) (dict-set! r k (hk-subst-apply s (get env k)))) (keys env))
+      r)))
+
+;; ─── Unification ─────────────────────────────────────────────────────────────
+
+(define
+  hk-bind-var
+  (fn
+    (v t)
+    (cond
+      ((and (hk-tvar? t) (= (hk-tvar-name t) v))
+       hk-subst-empty)
+      ((hk-infer-member? v (hk-ftv t))
+       (raise (str "Occurs check failed: " v " in " (hk-type->str t))))
+      (:else
+       (let ((s (dict)))
+         (dict-set! s v t)
+         s)))))
+
+(define
+  hk-zip-unify
+  (fn
+    (ts1 ts2 acc)
+    (if (or (empty? ts1) (empty? ts2))
+      acc
+      (let ((s (hk-unify (hk-subst-apply acc (first ts1))
+                         (hk-subst-apply acc (first ts2)))))
+        (hk-zip-unify (rest ts1) (rest ts2) (hk-subst-compose s acc))))))
+
+(define
+  hk-unify
+  (fn
+    (t1 t2)
+    (cond
+      ((and (hk-tvar? t1) (hk-tvar? t2) (= (hk-tvar-name t1) (hk-tvar-name t2)))
+       hk-subst-empty)
+      ((hk-tvar? t1) (hk-bind-var (hk-tvar-name t1) t2))
+      ((hk-tvar? t2) (hk-bind-var (hk-tvar-name t2) t1))
+      ((and (hk-tcon? t1) (hk-tcon? t2) (= (hk-tcon-name t1) (hk-tcon-name t2)))
+       hk-subst-empty)
+      ((and (hk-tarr? t1) (hk-tarr? t2))
+       (let ((s1 (hk-unify (hk-tarr-t1 t1) (hk-tarr-t1 t2))))
+         (let ((s2 (hk-unify (hk-subst-apply s1 (hk-tarr-t2 t1))
+                             (hk-subst-apply s1 (hk-tarr-t2 t2)))))
+           (hk-subst-compose s2 s1))))
+      ((and (hk-tapp? t1) (hk-tapp? t2))
+       (let ((s1 (hk-unify (hk-tapp-t1 t1) (hk-tapp-t1 t2))))
+         (let ((s2 (hk-unify (hk-subst-apply s1 (hk-tapp-t2 t1))
+                             (hk-subst-apply s1 (hk-tapp-t2 t2)))))
+           (hk-subst-compose s2 s1))))
+      ((and (hk-ttuple? t1) (hk-ttuple? t2)
+            (= (length (hk-ttuple-ts t1)) (length (hk-ttuple-ts t2))))
+       (hk-zip-unify (hk-ttuple-ts t1) (hk-ttuple-ts t2) hk-subst-empty))
+      (:else
+       (raise (str "Cannot unify " (hk-type->str t1) " with " (hk-type->str t2)))))))
+
+;; ─── Instantiation and generalization ────────────────────────────────────────
+
+(define
+  hk-instantiate
+  (fn
+    (t)
+    (if (not (hk-tscheme? t))
+      t
+      (let ((s (dict)))
+        (for-each (fn (v) (dict-set! s v (hk-fresh))) (hk-tscheme-vs t))
+        (hk-subst-apply s (hk-tscheme-type t))))))
+
+(define
+  hk-generalize
+  (fn
+    (env t)
+    (let ((free-t   (hk-nub (hk-ftv t)))
+          (free-env (hk-nub (hk-ftv-env env))))
+      (let ((bound (filter (fn (v) (not (hk-infer-member? v free-env))) free-t)))
+        (if (empty? bound)
+          t
+          (hk-tscheme bound t))))))
+
+;; ─── Pattern binding extraction ──────────────────────────────────────────────
+;; Returns a dict of name → type bindings introduced by matching pat against tv.
+
+(define
+  hk-w-pat
+  (fn
+    (pat tv)
+    (let ((tag (first pat)))
+      (cond
+        ((= tag "p-var")  (let ((d (dict))) (dict-set! d (nth pat 1) tv) d))
+        ((= tag "p-wild") (dict))
+        (:else            (dict))))))
+
+;; ─── Algorithm W ─────────────────────────────────────────────────────────────
+;; hk-w : env × expr → (list subst type)
+
+(define
+  hk-w-let
+  (fn
+    (env binds body)
+    ;; Infer types for each binding in order, generalising at each step.
+    (let
+      ((env2
+        (reduce
+          (fn
+            (cur-env b)
+            (let ((tag (first b)))
+              (cond
+                ;; Simple pattern binding: let x = expr
+                ((or (= tag "bind") (= tag "pat-bind"))
+                 (let ((pat  (nth b 1))
+                       (rhs  (nth b 2)))
+                   (let ((tv (hk-fresh)))
+                     (let ((r (hk-w cur-env rhs)))
+                       (let ((s1 (first r)) (t1 (nth r 1)))
+                         (let ((s2 (hk-unify (hk-subst-apply s1 tv) t1)))
+                           (let ((s (hk-subst-compose s2 s1)))
+                             (let ((t-gen (hk-generalize (hk-env-apply-subst s cur-env)
+                                                         (hk-subst-apply s t1))))
+                               (let ((bindings (hk-w-pat pat t-gen)))
+                                 (let ((r2 (hk-dict-copy cur-env)))
+                                   (for-each
+                                     (fn (k) (dict-set! r2 k (get bindings k)))
+                                     (keys bindings))
+                                   r2))))))))))
+                ;; Function clause: let f x y = expr
+                ((= tag "fun-clause")
+                 (let ((name (nth b 1))
+                       (pats (nth b 2))
+                       (body2 (nth b 3)))
+                   ;; Treat as: let name = lambda pats body2
+                   (let ((rhs (if (empty? pats)
+                                body2
+                                (list "lambda" pats body2))))
+                     (let ((tv (hk-fresh)))
+                       (let ((env-rec (hk-dict-copy cur-env)))
+                         (dict-set! env-rec name tv)
+                         (let ((r (hk-w env-rec rhs)))
+                           (let ((s1 (first r)) (t1 (nth r 1)))
+                             (let ((s2 (hk-unify (hk-subst-apply s1 tv) t1)))
+                               (let ((s (hk-subst-compose s2 s1)))
+                                 (let ((t-gen (hk-generalize
+                                                (hk-env-apply-subst s cur-env)
+                                                (hk-subst-apply s t1))))
+                                   (let ((r2 (hk-dict-copy cur-env)))
+                                     (dict-set! r2 name t-gen)
+                                     r2)))))))))))
+                (:else cur-env))))
+          env
+          binds)))
+      (hk-w env2 body))))
+
+(define
+  hk-w
+  (fn
+    (env expr)
+    (let ((tag (first expr)))
+      (cond
+        ;; Literals
+        ((= tag "int")    (list hk-subst-empty hk-t-int))
+        ((= tag "float")  (list hk-subst-empty hk-t-float))
+        ((= tag "string") (list hk-subst-empty hk-t-string))
+        ((= tag "char")   (list hk-subst-empty hk-t-char))
+
+        ;; Variable
+        ((= tag "var")
+         (let ((name (nth expr 1)))
+           (let ((scheme (get env name)))
+             (if (nil? scheme)
+               (raise (str "Unbound variable: " name))
+               (list hk-subst-empty (hk-instantiate scheme))))))
+
+        ;; Constructor (same lookup as var)
+        ((= tag "con")
+         (let ((name (nth expr 1)))
+           (let ((scheme (get env name)))
+             (if (nil? scheme)
+               (list hk-subst-empty (hk-fresh))
+               (list hk-subst-empty (hk-instantiate scheme))))))
+
+        ;; Unary negation
+        ((= tag "neg")
+         (let ((r (hk-w env (nth expr 1))))
+           (let ((s1 (first r)) (t1 (nth r 1)))
+             (let ((s2 (hk-unify t1 hk-t-int)))
+               (list (hk-subst-compose s2 s1) hk-t-int)))))
+
+        ;; Lambda: ("lambda" pats body)
+        ((= tag "lambda")
+         (let ((pats (nth expr 1))
+               (body (nth expr 2)))
+           (if (empty? pats)
+             (hk-w env body)
+             (let ((pat  (first pats))
+                   (rest (rest pats)))
+               (let ((tv (hk-fresh)))
+                 (let ((bindings (hk-w-pat pat tv)))
+                   (let ((env2 (hk-dict-copy env)))
+                     (for-each (fn (k) (dict-set! env2 k (get bindings k))) (keys bindings))
+                     (let ((inner (if (empty? rest)
+                                    body
+                                    (list "lambda" rest body))))
+                       (let ((r (hk-w env2 inner)))
+                         (let ((s1 (first r)) (t1 (nth r 1)))
+                           (list s1 (hk-tarr (hk-subst-apply s1 tv) t1))))))))))))
+
+        ;; Application: ("app" f x)
+        ((= tag "app")
+         (let ((tv (hk-fresh)))
+           (let ((r1 (hk-w env (nth expr 1))))
+             (let ((s1 (first r1)) (tf (nth r1 1)))
+               (let ((r2 (hk-w (hk-env-apply-subst s1 env) (nth expr 2))))
+                 (let ((s2 (first r2)) (tx (nth r2 1)))
+                   (let ((s3 (hk-unify (hk-subst-apply s2 tf) (hk-tarr tx tv))))
+                     (let ((s (hk-subst-compose s3 (hk-subst-compose s2 s1))))
+                       (list s (hk-subst-apply s3 tv))))))))))
+
+        ;; Let: ("let" binds body)
+        ((= tag "let")
+         (hk-w-let env (nth expr 1) (nth expr 2)))
+
+        ;; If: ("if" cond then else)
+        ((= tag "if")
+         (let ((r1 (hk-w env (nth expr 1))))
+           (let ((s1 (first r1)) (tc (nth r1 1)))
+             (let ((s2 (hk-unify tc hk-t-bool)))
+               (let ((s12 (hk-subst-compose s2 s1)))
+                 (let ((r2 (hk-w (hk-env-apply-subst s12 env) (nth expr 2))))
+                   (let ((s3 (first r2)) (tt (nth r2 1)))
+                     (let ((s123 (hk-subst-compose s3 s12)))
+                       (let ((r3 (hk-w (hk-env-apply-subst s123 env) (nth expr 3))))
+                         (let ((s4 (first r3)) (te (nth r3 1)))
+                           (let ((s5 (hk-unify (hk-subst-apply s4 tt) te)))
+                             (let ((s (hk-subst-compose s5 (hk-subst-compose s4 s123))))
+                               (list s (hk-subst-apply s5 te))))))))))))))
+
+        ;; Binary operator: ("op" op-name left right)
+        ;; Desugar to double application.
+        ((= tag "op")
+         (hk-w env
+               (list "app"
+                     (list "app" (list "var" (nth expr 1)) (nth expr 2))
+                     (nth expr 3))))
+
+        ;; Tuple: ("tuple" [e1 e2 ...])
+        ((= tag "tuple")
+         (let ((elems (nth expr 1)))
+           (let ((s-acc hk-subst-empty)
+                 (ts    (list)))
+             (for-each
+               (fn (e)
+                 (let ((r (hk-w (hk-env-apply-subst s-acc env) e)))
+                   (set! s-acc (hk-subst-compose (first r) s-acc))
+                   (set! ts    (append ts (list (nth r 1))))))
+               elems)
+             (list s-acc (hk-ttuple (map (fn (t) (hk-subst-apply s-acc t)) ts))))))
+
+        ;; List literal: ("list" [e1 e2 ...])
+        ((= tag "list")
+         (let ((elems (nth expr 1)))
+           (if (empty? elems)
+             (list hk-subst-empty (hk-t-list (hk-fresh)))
+             (let ((tv (hk-fresh)))
+               (let ((s-acc hk-subst-empty))
+                 (for-each
+                   (fn (e)
+                     (let ((r (hk-w (hk-env-apply-subst s-acc env) e)))
+                       (let ((s2 (first r)) (te (nth r 1)))
+                         (let ((s3 (hk-unify (hk-subst-apply s2 tv) te)))
+                           (set! s-acc (hk-subst-compose s3 (hk-subst-compose s2 s-acc)))))))
+                   elems)
+                 (list s-acc (hk-t-list (hk-subst-apply s-acc tv))))))))
+
+        ;; Location annotation: just delegate — position is for outer context.
+        ((= tag "loc")
+         (hk-w env (nth expr 3)))
+
+        (:else
+         (raise (str "hk-w: unhandled tag: " tag)))))))
+
+;; ─── Initial type environment ─────────────────────────────────────────────────
+;; Monomorphic numeric ops (no Num typeclass yet — upgraded in Phase 5).
+
+(define
+  hk-type-env0
+  (fn ()
+    (let ((env (dict)))
+      ;; Integer arithmetic
+      (for-each
+        (fn (op)
+          (dict-set! env op (hk-tarr hk-t-int (hk-tarr hk-t-int hk-t-int))))
+        (list "+" "-" "*" "div" "mod" "quot" "rem"))
+      ;; Integer comparison → Bool
+      (for-each
+        (fn (op)
+          (dict-set! env op (hk-tarr hk-t-int (hk-tarr hk-t-int hk-t-bool))))
+        (list "==" "/=" "<" "<=" ">" ">="))
+      ;; Boolean operators
+      (dict-set! env "&&" (hk-tarr hk-t-bool (hk-tarr hk-t-bool hk-t-bool)))
+      (dict-set! env "||" (hk-tarr hk-t-bool (hk-tarr hk-t-bool hk-t-bool)))
+      (dict-set! env "not" (hk-tarr hk-t-bool hk-t-bool))
+      ;; Constructors
+      (dict-set! env "True"  hk-t-bool)
+      (dict-set! env "False" hk-t-bool)
+      ;; Polymorphic list ops (using TScheme)
+      (let ((a (hk-tvar "a")))
+        (dict-set! env "head"  (hk-tscheme (list "a") (hk-tarr (hk-t-list a) a)))
+        (dict-set! env "tail"  (hk-tscheme (list "a") (hk-tarr (hk-t-list a) (hk-t-list a))))
+        (dict-set! env "null"  (hk-tscheme (list "a") (hk-tarr (hk-t-list a) hk-t-bool)))
+        (dict-set! env "length" (hk-tscheme (list "a") (hk-tarr (hk-t-list a) hk-t-int)))
+        (dict-set! env "reverse" (hk-tscheme (list "a") (hk-tarr (hk-t-list a) (hk-t-list a))))
+        (dict-set! env ":"
+          (hk-tscheme (list "a") (hk-tarr a (hk-tarr (hk-t-list a) (hk-t-list a))))))
+      ;; negate
+      (dict-set! env "negate" (hk-tarr hk-t-int hk-t-int))
+      (dict-set! env "abs"    (hk-tarr hk-t-int hk-t-int))
+      env)))
+
+;; ─── Expression brief printer ────────────────────────────────────────────────
+;; Produces a short human-readable label for an AST node used in error messages.
+
+(define
+  hk-expr->brief
+  (fn
+    (expr)
+    (cond
+      ((not (list? expr)) (str expr))
+      ((empty? expr)      "()")
+      (:else
+       (let ((tag (first expr)))
+         (cond
+           ((= tag "var")    (nth expr 1))
+           ((= tag "con")    (nth expr 1))
+           ((= tag "int")    (str (nth expr 1)))
+           ((= tag "float")  (str (nth expr 1)))
+           ((= tag "string") (str "\"" (nth expr 1) "\""))
+           ((= tag "char")   (str "'" (nth expr 1) "'"))
+           ((= tag "neg")    (str "(-" (hk-expr->brief (nth expr 1)) ")"))
+           ((= tag "app")
+            (str "(" (hk-expr->brief (nth expr 1))
+                 " " (hk-expr->brief (nth expr 2)) ")"))
+           ((= tag "op")
+            (str "(" (hk-expr->brief (nth expr 2))
+                 " " (nth expr 1)
+                 " " (hk-expr->brief (nth expr 3)) ")"))
+           ((= tag "lambda") "(\\ ...)")
+           ((= tag "let")    "(let ...)")
+           ((= tag "if")     "(if ...)")
+           ((= tag "tuple")  "(tuple ...)")
+           ((= tag "list")   "[...]")
+           ((= tag "loc")    (hk-expr->brief (nth expr 3)))
+           (:else            (str "(" tag " ..."))))))))
+
+;; ─── Loc-annotated inference ──────────────────────────────────────────────────
+;; ("loc" LINE COL INNER) node: hk-w catches any error and re-raises with
+;; "at LINE:COL: " prepended.  Emitted by the parser or test scaffolding.
+
+;; Extended hk-w handles "loc" — handled inline in the cond below.
+
+;; ─── Program-level inference ─────────────────────────────────────────────────
+;; hk-infer-decl : env × decl → ("ok" name type-str) | ("err" msg) | nil
+;;   Uses tagged results so callers don't need re-raise.
+
+(define
+  hk-infer-decl
+  (fn
+    (env decl)
+    (let
+      ((tag (first decl)))
+      (cond
+        ((= tag "fun-clause")
+          (let
+            ((name (nth decl 1)) (pats (nth decl 2)) (body (nth decl 3)))
+            (let
+              ((rhs (if (empty? pats) body (list "lambda" pats body))))
+              (guard
+                (e (#t (list "err" (str "in '" name "': " e))))
+                (begin
+                  (hk-reset-fresh)
+                  (let
+                    ((r (hk-w env rhs)))
+                    (let
+                      ((final-type (hk-subst-apply (first r) (nth r 1))))
+                      (list "ok" name (hk-type->str final-type) final-type))))))))
+        ((or (= tag "bind") (= tag "pat-bind"))
+          (let
+            ((pat (nth decl 1)) (body (nth decl 2)))
+            (let
+              ((label (if (and (list? pat) (= (first pat) "p-var")) (nth pat 1) "<binding>")))
+              (guard
+                (e (#t (list "err" (str "in '" label "': " e))))
+                (begin
+                  (hk-reset-fresh)
+                  (let
+                    ((r (hk-w env body)))
+                    (let
+                      ((final-type (hk-subst-apply (first r) (nth r 1))))
+                      (list "ok" label (hk-type->str final-type) final-type))))))))
+        (:else nil)))))
+
+;; hk-infer-prog : program-ast × env → list of ("ok" name type) | ("err" msg)
+
+(define
+  hk-ast-type
+  (fn
+    (ast)
+    (let
+      ((tag (first ast)))
+      (cond
+        ((= tag "t-con") (list "TCon" (nth ast 1)))
+        ((= tag "t-var") (list "TVar" (nth ast 1)))
+        ((= tag "t-fun")
+          (list "TArr" (hk-ast-type (nth ast 1)) (hk-ast-type (nth ast 2))))
+        ((= tag "t-app")
+          (list "TApp" (hk-ast-type (nth ast 1)) (hk-ast-type (nth ast 2))))
+        ((= tag "t-list")
+          (list "TApp" (list "TCon" "[]") (hk-ast-type (nth ast 1))))
+        ((= tag "t-tuple") (list "TTuple" (map hk-ast-type (nth ast 1))))
+        (:else (raise (str "unknown type node: " (first ast))))))))
+
+;; ─── Convenience ─────────────────────────────────────────────────────────────
+;; hk-infer-type : Haskell expression source → inferred type string
+
+(define
+  hk-collect-tvars
+  (fn
+    (t acc)
+    (cond
+      ((= (first t) "TVar")
+        (if
+          (some (fn (v) (= v (nth t 1))) acc)
+          acc
+          (begin (append! acc (nth t 1)) acc)))
+      ((= (first t) "TArr")
+        (hk-collect-tvars (nth t 2) (hk-collect-tvars (nth t 1) acc)))
+      ((= (first t) "TApp")
+        (hk-collect-tvars (nth t 2) (hk-collect-tvars (nth t 1) acc)))
+      ((= (first t) "TTuple")
+        (reduce (fn (a elem) (hk-collect-tvars elem a)) acc (nth t 1)))
+      (:else acc))))
+
+(define
+  hk-check-sig
+  (fn
+    (declared-ast inferred-type)
+    (let
+      ((declared (hk-ast-type declared-ast)))
+      (let
+        ((tvars (hk-collect-tvars declared (list))))
+        (let
+          ((scheme (if (empty? tvars) declared (list "TScheme" tvars declared))))
+          (let
+            ((inst (hk-instantiate scheme)))
+            (hk-unify inst inferred-type)))))))
+
+(define
+  hk-infer-prog
+  (fn
+    (prog env)
+    (let
+      ((decls (cond ((and (list? prog) (= (first prog) "program")) (nth prog 1)) ((and (list? prog) (= (first prog) "module")) (nth prog 3)) (:else (list))))
+        (results (list))
+        (sigs (dict)))
+      (for-each
+        (fn
+          (d)
+          (when
+            (= (first d) "type-sig")
+            (let
+              ((names (nth d 1)) (type-ast (nth d 2)))
+              (for-each (fn (n) (dict-set! sigs n type-ast)) names))))
+        decls)
+      (for-each
+        (fn
+          (d)
+          (let
+            ((r (hk-infer-decl env d)))
+            (when
+              (not (nil? r))
+              (let
+                ((checked (if (and (= (first r) "ok") (has-key? sigs (nth r 1))) (guard (e (true (list "err" (str "in '" (nth r 1) "': declared type mismatch: " e)))) (begin (hk-check-sig (get sigs (nth r 1)) (nth r 3)) r)) r)))
+                (append! results checked)
+                (when
+                  (= (first checked) "ok")
+                  (dict-set! env (nth checked 1) (nth checked 3)))))))
+        decls)
+      results)))
+
+(define
+  hk-infer-type
+  (fn
+    (src)
+    (hk-reset-fresh)
+    (let
+      ((ast (hk-core-expr src)) (env (hk-type-env0)))
+      (let
+        ((r (hk-w env ast)))
+        (hk-type->str (hk-subst-apply (first r) (nth r 1)))))))

lib/haskell/layout.sx

@@ -0,0 +1,329 @@
+;; Haskell 98 layout algorithm (§10.3).
+;;
+;; Consumes the raw token stream produced by hk-tokenize and inserts
+;; virtual braces / semicolons (types vlbrace / vrbrace / vsemi) based
+;; on indentation. Newline tokens are consumed and stripped.
+;;
+;;   (hk-layout (hk-tokenize src))  →  tokens-with-virtual-layout
+
+;; ── Pre-pass ──────────────────────────────────────────────────────
+;;
+;; Walks the raw token list and emits an augmented stream containing
+;; two fresh pseudo-tokens:
+;;
+;;   {:type "layout-open"   :col N :keyword K}
+;;     At stream start (K = "<module>") unless the first real token is
+;;     `module` or `{`. Also immediately after every `let` / `where` /
+;;     `do` / `of` whose following token is NOT `{`. N is the column
+;;     of the token that follows.
+;;
+;;   {:type "layout-indent" :col N}
+;;     Before any token whose line is strictly greater than the line
+;;     of the previously emitted real token, EXCEPT when that token
+;;     is already preceded by a layout-open (Haskell 98 §10.3 note 3).
+;;
+;; Raw newline tokens are dropped.
+
+(define
+  hk-layout-keyword?
+  (fn
+    (tok)
+    (and
+      (= (get tok "type") "reserved")
+      (or
+        (= (get tok "value") "let")
+        (= (get tok "value") "where")
+        (= (get tok "value") "do")
+        (= (get tok "value") "of")))))
+
+(define
+  hk-layout-pre
+  (fn
+    (tokens)
+    (let
+      ((result (list))
+        (n (len tokens))
+        (i 0)
+        (prev-line -1)
+        (first-real-emitted false)
+        (suppress-next-indent false))
+      (define
+        hk-next-real-idx
+        (fn
+          (start)
+          (let
+            ((j start))
+            (define
+              hk-nri-loop
+              (fn
+                ()
+                (when
+                  (and
+                    (< j n)
+                    (= (get (nth tokens j) "type") "newline"))
+                  (do (set! j (+ j 1)) (hk-nri-loop)))))
+            (hk-nri-loop)
+            j)))
+      (define
+        hk-pre-step
+        (fn
+          ()
+          (when
+            (< i n)
+            (let
+              ((tok (nth tokens i)) (ty (get tok "type")))
+              (cond
+                ((= ty "newline") (do (set! i (+ i 1)) (hk-pre-step)))
+                (:else
+                  (do
+                    (when
+                      (not first-real-emitted)
+                      (do
+                        (set! first-real-emitted true)
+                        (when
+                          (not
+                            (or
+                              (and
+                                (= ty "reserved")
+                                (= (get tok "value") "module"))
+                              (= ty "lbrace")))
+                          (do
+                            (append!
+                              result
+                              {:type "layout-open"
+                                :col (get tok "col")
+                                :keyword "<module>"
+                                :line (get tok "line")})
+                            (set! suppress-next-indent true)))))
+                    (when
+                      (and
+                        (>= prev-line 0)
+                        (> (get tok "line") prev-line)
+                        (not suppress-next-indent))
+                      (append!
+                        result
+                        {:type "layout-indent"
+                          :col (get tok "col")
+                          :line (get tok "line")}))
+                    (set! suppress-next-indent false)
+                    (set! prev-line (get tok "line"))
+                    (append! result tok)
+                    (when
+                      (hk-layout-keyword? tok)
+                      (let
+                        ((j (hk-next-real-idx (+ i 1))))
+                        (cond
+                          ((>= j n)
+                            (do
+                              (append!
+                                result
+                                {:type "layout-open"
+                                  :col 0
+                                  :keyword (get tok "value")
+                                  :line (get tok "line")})
+                              (set! suppress-next-indent true)))
+                          ((= (get (nth tokens j) "type") "lbrace") nil)
+                          (:else
+                            (do
+                              (append!
+                                result
+                                {:type "layout-open"
+                                  :col (get (nth tokens j) "col")
+                                  :keyword (get tok "value")
+                                  :line (get tok "line")})
+                              (set! suppress-next-indent true))))))
+                    (set! i (+ i 1))
+                    (hk-pre-step))))))))
+      (hk-pre-step)
+      result)))
+
+;; ── Main pass: L algorithm ────────────────────────────────────────
+;;
+;; Stack is a list; the head is the top of stack. Each entry is
+;; either the keyword :explicit (pushed by an explicit `{`) or a dict
+;; {:col N :keyword K} pushed by a layout-open marker.
+;;
+;; Rules (following Haskell 98 §10.3):
+;;
+;;   layout-open(n)  vs stack:
+;;     empty or explicit top                 → push n; emit {
+;;     n > top-col                           → push n; emit {
+;;     otherwise                             → emit { }; retry as indent(n)
+;;
+;;   layout-indent(n) vs stack:
+;;     empty or explicit top                 → drop
+;;     n == top-col                          → emit ;
+;;     n <  top-col                          → emit }; pop; recurse
+;;     n >  top-col                          → drop
+;;
+;;   lbrace                                  → push :explicit; emit {
+;;   rbrace                                  → pop if :explicit; emit }
+;;   `in` with implicit let on top           → emit }; pop; emit in
+;;   any other token                         → emit
+;;
+;; EOF: emit } for every remaining implicit context.
+
+(define
+  hk-layout-L
+  (fn
+    (pre-toks)
+    (let
+      ((result (list))
+        (stack (list))
+        (n (len pre-toks))
+        (i 0))
+      (define hk-emit (fn (t) (append! result t)))
+      (define
+        hk-indent-at
+        (fn
+          (col line)
+          (cond
+            ((or (empty? stack) (= (first stack) :explicit)) nil)
+            (:else
+              (let
+                ((top-col (get (first stack) "col")))
+                (cond
+                  ((= col top-col)
+                    (hk-emit
+                      {:type "vsemi" :value ";" :line line :col col}))
+                  ((< col top-col)
+                    (do
+                      (hk-emit
+                        {:type "vrbrace" :value "}" :line line :col col})
+                      (set! stack (rest stack))
+                      (hk-indent-at col line)))
+                  (:else nil)))))))
+      (define
+        hk-open-at
+        (fn
+          (col keyword line)
+          (cond
+            ((and
+                (> col 0)
+                (or
+                  (empty? stack)
+                  (= (first stack) :explicit)
+                  (> col (get (first stack) "col"))))
+              (do
+                (hk-emit
+                  {:type "vlbrace" :value "{" :line line :col col})
+                (set! stack (cons {:col col :keyword keyword} stack))))
+            (:else
+              (do
+                (hk-emit
+                  {:type "vlbrace" :value "{" :line line :col col})
+                (hk-emit
+                  {:type "vrbrace" :value "}" :line line :col col})
+                (hk-indent-at col line))))))
+      (define
+        hk-close-eof
+        (fn
+          ()
+          (when
+            (and
+              (not (empty? stack))
+              (not (= (first stack) :explicit)))
+            (do
+              (hk-emit {:type "vrbrace" :value "}" :line 0 :col 0})
+              (set! stack (rest stack))
+              (hk-close-eof)))))
+      ;; Peek past further layout-indent / layout-open markers to find
+      ;; the next real token's value when its type is `reserved`.
+      ;; Returns nil if no such token.
+      (define
+        hk-peek-next-reserved
+        (fn
+          (start)
+          (let ((j (+ start 1)) (found nil) (done false))
+            (define
+              hk-pnr-loop
+              (fn
+                ()
+                (when
+                  (and (not done) (< j n))
+                  (let
+                    ((t (nth pre-toks j)) (ty (get t "type")))
+                    (cond
+                      ((or
+                          (= ty "layout-indent")
+                          (= ty "layout-open"))
+                        (do (set! j (+ j 1)) (hk-pnr-loop)))
+                      ((= ty "reserved")
+                        (do (set! found (get t "value")) (set! done true)))
+                      (:else (set! done true)))))))
+            (hk-pnr-loop)
+            found)))
+      (define
+        hk-layout-step
+        (fn
+          ()
+          (when
+            (< i n)
+            (let
+              ((tok (nth pre-toks i)) (ty (get tok "type")))
+              (cond
+                ((= ty "eof")
+                  (do
+                    (hk-close-eof)
+                    (hk-emit tok)
+                    (set! i (+ i 1))
+                    (hk-layout-step)))
+                ((= ty "layout-open")
+                  (do
+                    (hk-open-at
+                      (get tok "col")
+                      (get tok "keyword")
+                      (get tok "line"))
+                    (set! i (+ i 1))
+                    (hk-layout-step)))
+                ((= ty "layout-indent")
+                  (cond
+                    ((= (hk-peek-next-reserved i) "in")
+                      (do (set! i (+ i 1)) (hk-layout-step)))
+                    (:else
+                      (do
+                        (hk-indent-at (get tok "col") (get tok "line"))
+                        (set! i (+ i 1))
+                        (hk-layout-step)))))
+                ((= ty "lbrace")
+                  (do
+                    (set! stack (cons :explicit stack))
+                    (hk-emit tok)
+                    (set! i (+ i 1))
+                    (hk-layout-step)))
+                ((= ty "rbrace")
+                  (do
+                    (when
+                      (and
+                        (not (empty? stack))
+                        (= (first stack) :explicit))
+                      (set! stack (rest stack)))
+                    (hk-emit tok)
+                    (set! i (+ i 1))
+                    (hk-layout-step)))
+                ((and
+                    (= ty "reserved")
+                    (= (get tok "value") "in")
+                    (not (empty? stack))
+                    (not (= (first stack) :explicit))
+                    (= (get (first stack) "keyword") "let"))
+                  (do
+                    (hk-emit
+                      {:type "vrbrace"
+                        :value "}"
+                        :line (get tok "line")
+                        :col (get tok "col")})
+                    (set! stack (rest stack))
+                    (hk-emit tok)
+                    (set! i (+ i 1))
+                    (hk-layout-step)))
+                (:else
+                  (do
+                    (hk-emit tok)
+                    (set! i (+ i 1))
+                    (hk-layout-step))))))))
+      (hk-layout-step)
+      (hk-close-eof)
+      result)))
+
+(define hk-layout (fn (tokens) (hk-layout-L (hk-layout-pre tokens))))

lib/haskell/match.sx

@@ -0,0 +1,201 @@
+;; Value-level pattern matching.
+;;
+;; Constructor values are tagged lists whose first element is the
+;; constructor name (a string). Tuples use the special tag "Tuple".
+;; Lists use the spine of `:` cons and `[]` nil.
+;;
+;;   Just 5         →  ("Just" 5)
+;;   Nothing        →  ("Nothing")
+;;   (1, 2)         →  ("Tuple" 1 2)
+;;   [1, 2]         →  (":" 1 (":" 2 ("[]")))
+;;   ()             →  ("()")
+;;
+;; Primitive values (numbers, strings, chars) are stored raw.
+;;
+;; The matcher takes a pattern AST node, a value, and an environment
+;; dict; it returns an extended dict on success, or `nil` on failure.
+
+;; ── Value builders ──────────────────────────────────────────
+(define
+  hk-mk-con
+  (fn
+    (cname args)
+    (let ((result (list cname)))
+      (for-each (fn (a) (append! result a)) args)
+      result)))
+
+(define
+  hk-mk-tuple
+  (fn
+    (items)
+    (let ((result (list "Tuple")))
+      (for-each (fn (x) (append! result x)) items)
+      result)))
+
+(define hk-mk-nil (fn () (list "[]")))
+
+(define hk-mk-cons (fn (h t) (list ":" h t)))
+
+(define
+  hk-mk-list
+  (fn
+    (items)
+    (cond
+      ((empty? items) (hk-mk-nil))
+      (:else
+        (hk-mk-cons (first items) (hk-mk-list (rest items)))))))
+
+;; ── Predicates / accessors on constructor values ───────────
+(define
+  hk-is-con-val?
+  (fn
+    (v)
+    (and
+      (list? v)
+      (not (empty? v))
+      (string? (first v)))))
+
+(define hk-val-con-name (fn (v) (first v)))
+
+(define hk-val-con-args (fn (v) (rest v)))
+
+;; ── The matcher ────────────────────────────────────────────
+;;
+;; Pattern match forces the scrutinee to WHNF before inspecting it
+;; — except for `p-wild`, `p-var`, and `p-lazy`, which never need
+;; to look at the value. Args of constructor / tuple / list values
+;; remain thunked (they're forced only when their own pattern needs
+;; to inspect them, recursively).
+(define
+  hk-match
+  (fn
+    (pat val env)
+    (cond
+      ((not (list? pat)) nil)
+      ((empty? pat) nil)
+      (:else
+        (let
+          ((tag (first pat)))
+          (cond
+            ((= tag "p-wild") env)
+            ((= tag "p-var") (assoc env (nth pat 1) val))
+            ((= tag "p-lazy") (hk-match (nth pat 1) val env))
+            ((= tag "p-as")
+              (let
+                ((res (hk-match (nth pat 2) val env)))
+                (cond
+                  ((nil? res) nil)
+                  (:else (assoc res (nth pat 1) val)))))
+            (:else
+              (let ((fv (hk-force val)))
+                (cond
+                  ((= tag "p-int")
+                    (if
+                      (and (number? fv) (= fv (nth pat 1)))
+                      env
+                      nil))
+                  ((= tag "p-float")
+                    (if
+                      (and (number? fv) (= fv (nth pat 1)))
+                      env
+                      nil))
+                  ((= tag "p-string")
+                    (if
+                      (and (string? fv) (= fv (nth pat 1)))
+                      env
+                      nil))
+                  ((= tag "p-char")
+                    (if
+                      (and (string? fv) (= fv (nth pat 1)))
+                      env
+                      nil))
+                  ((= tag "p-con")
+                    (let
+                      ((pat-name (nth pat 1)) (pat-args (nth pat 2)))
+                      (cond
+                        ((not (hk-is-con-val? fv)) nil)
+                        ((not (= (hk-val-con-name fv) pat-name)) nil)
+                        (:else
+                          (let
+                            ((val-args (hk-val-con-args fv)))
+                            (cond
+                              ((not (= (len pat-args) (len val-args)))
+                                nil)
+                              (:else
+                                (hk-match-all
+                                  pat-args
+                                  val-args
+                                  env))))))))
+                  ((= tag "p-tuple")
+                    (let
+                      ((items (nth pat 1)))
+                      (cond
+                        ((not (hk-is-con-val? fv)) nil)
+                        ((not (= (hk-val-con-name fv) "Tuple")) nil)
+                        ((not (= (len (hk-val-con-args fv)) (len items)))
+                          nil)
+                        (:else
+                          (hk-match-all
+                            items
+                            (hk-val-con-args fv)
+                            env)))))
+                  ((= tag "p-list")
+                    (hk-match-list-pat (nth pat 1) fv env))
+                  (:else nil))))))))))
+
+(define
+  hk-match-all
+  (fn
+    (pats vals env)
+    (cond
+      ((empty? pats) env)
+      (:else
+        (let
+          ((res (hk-match (first pats) (first vals) env)))
+          (cond
+            ((nil? res) nil)
+            (:else
+              (hk-match-all (rest pats) (rest vals) res))))))))
+
+(define
+  hk-match-list-pat
+  (fn
+    (items val env)
+    (let ((fv (hk-force val)))
+      (cond
+        ((empty? items)
+          (if
+            (and
+              (hk-is-con-val? fv)
+              (= (hk-val-con-name fv) "[]"))
+            env
+            nil))
+        (:else
+          (cond
+            ((not (hk-is-con-val? fv)) nil)
+            ((not (= (hk-val-con-name fv) ":")) nil)
+            (:else
+              (let
+                ((args (hk-val-con-args fv)))
+                (let
+                  ((h (first args)) (t (first (rest args))))
+                  (let
+                    ((res (hk-match (first items) h env)))
+                    (cond
+                      ((nil? res) nil)
+                      (:else
+                        (hk-match-list-pat
+                          (rest items)
+                          t
+                          res)))))))))))))
+
+;; ── Convenience: parse a pattern from source for tests ─────
+;; (Uses the parser's case-alt entry — `case _ of pat -> 0` —
+;; to extract a pattern AST.)
+(define
+  hk-parse-pat-source
+  (fn
+    (src)
+    (let
+      ((expr (hk-parse (str "case 0 of " src " -> 0"))))
+      (nth (nth (nth expr 2) 0) 1))))

lib/haskell/runtime.sx

@@ -1,507 +1,130 @@
-;; lib/haskell/runtime.sx — Haskell-on-SX runtime layer
+;; Haskell runtime: constructor registry.
 ;;
-;; Covers the Haskell primitives now reachable via SX spec:
-;;  1. Numeric type class helpers (Num / Integral / Fractional)
-;;  2. Rational numbers (dict-based: {:_rational true :num n :den d})
-;;  3. Lazy evaluation — hk-force for promises created by delay
-;;  4. Char utilities (Data.Char)
-;;  5. Data.Set wrappers
-;;  6. Data.List utilities
-;;  7. Maybe / Either ADTs
-;;  8. Tuples (lists, since list->vector unreliable in sx_server)
-;;  9. String helpers (words/lines/isPrefixOf/etc.)
-;; 10. Show helper
+;; A mutable dict keyed by constructor name (e.g. "Just", "[]") with
+;; entries of shape  {:arity N :type TYPE-NAME-STRING}.
+;; Populated by ingesting `data` / `newtype` decls from parsed ASTs.
+;; Pre-registers a small set of constructors tied to Haskell syntactic
+;; forms (Bool, list, unit) — every nontrivial program depends on
+;; these, and the parser/desugar pipeline emits them as (:var "True")
+;; etc. without a corresponding `data` decl.
 
-;; ===========================================================================
-;; 1. Numeric type class helpers
-;; ===========================================================================
-
-(define hk-is-integer? integer?)
-(define hk-is-float? float?)
-(define hk-is-num? number?)
-
-;; fromIntegral — coerce integer to Float
-(define (hk-to-float x) (exact->inexact x))
-
-;; truncate / round toward zero
-(define hk-to-integer truncate)
-(define hk-from-integer (fn (n) n))
-
-;; Haskell div: floor division (rounds toward -inf)
-(define
-  (hk-div a b)
-  (let
-    ((q (quotient a b)) (r (remainder a b)))
-    (if
-      (and
-        (not (= r 0))
-        (or
-          (and (< a 0) (> b 0))
-          (and (> a 0) (< b 0))))
-      (- q 1)
-      q)))
-
-;; Haskell mod: result has same sign as divisor
-(define hk-mod modulo)
-
-;; Haskell rem: result has same sign as dividend
-(define hk-rem remainder)
-
-;; Haskell quot: truncation division
-(define hk-quot quotient)
-
-;; divMod and quotRem return pairs (lists)
-(define (hk-div-mod a b) (list (hk-div a b) (hk-mod a b)))
-(define (hk-quot-rem a b) (list (hk-quot a b) (hk-rem a b)))
-
-(define (hk-abs x) (if (< x 0) (- 0 x) x))
-(define
-  (hk-signum x)
-  (cond
-    ((> x 0) 1)
-    ((< x 0) -1)
-    (else 0)))
-
-(define hk-gcd gcd)
-(define hk-lcm lcm)
-
-(define (hk-even? n) (= (modulo n 2) 0))
-(define (hk-odd? n) (not (= (modulo n 2) 0)))
-
-;; ===========================================================================
-;; 2. Rational numbers (dict implementation — no built-in rational in sx_server)
-;; ===========================================================================
+(define hk-constructors (dict))
 
 (define
-  (hk-make-rational n d)
-  (let
-    ((g (gcd (hk-abs n) (hk-abs d))))
-    (if (< d 0) {:num (quotient (- 0 n) g) :den (quotient (- 0 d) g) :_rational true} {:num (quotient n g) :den (quotient d g) :_rational true})))
-
-(define
-  (hk-rational? x)
-  (and (dict? x) (not (= (get x :_rational) nil))))
-(define (hk-numerator r) (get r :num))
-(define (hk-denominator r) (get r :den))
-
-(define
-  (hk-rational-add r1 r2)
-  (hk-make-rational
-    (+
-      (* (hk-numerator r1) (hk-denominator r2))
-      (* (hk-numerator r2) (hk-denominator r1)))
-    (* (hk-denominator r1) (hk-denominator r2))))
-
-(define
-  (hk-rational-sub r1 r2)
-  (hk-make-rational
-    (-
-      (* (hk-numerator r1) (hk-denominator r2))
-      (* (hk-numerator r2) (hk-denominator r1)))
-    (* (hk-denominator r1) (hk-denominator r2))))
-
-(define
-  (hk-rational-mul r1 r2)
-  (hk-make-rational
-    (* (hk-numerator r1) (hk-numerator r2))
-    (* (hk-denominator r1) (hk-denominator r2))))
-
-(define
-  (hk-rational-div r1 r2)
-  (hk-make-rational
-    (* (hk-numerator r1) (hk-denominator r2))
-    (* (hk-denominator r1) (hk-numerator r2))))
-
-(define
-  (hk-rational-to-float r)
-  (exact->inexact (/ (hk-numerator r) (hk-denominator r))))
-
-(define (hk-show-rational r) (str (hk-numerator r) "%" (hk-denominator r)))
-
-;; ===========================================================================
-;; 3. Lazy evaluation — promises (created via SX delay)
-;; ===========================================================================
-
-(define
-  (hk-force p)
-  (if
-    (and (dict? p) (not (= (get p :_promise) nil)))
-    (if (get p :forced) (get p :value) ((get p :thunk)))
-    p))
-
-;; ===========================================================================
-;; 4. Char utilities (Data.Char)
-;; ===========================================================================
-
-(define hk-ord char->integer)
-(define hk-chr integer->char)
-
-;; Inline ASCII predicates — char-alphabetic?/char-numeric? unreliable in sx_server
-(define
-  (hk-is-alpha? c)
-  (let
-    ((n (char->integer c)))
-    (or
-      (and (>= n 65) (<= n 90))
-      (and (>= n 97) (<= n 122)))))
-
-(define
-  (hk-is-digit? c)
-  (let ((n (char->integer c))) (and (>= n 48) (<= n 57))))
-
-(define
-  (hk-is-alnum? c)
-  (let
-    ((n (char->integer c)))
-    (or
-      (and (>= n 48) (<= n 57))
-      (and (>= n 65) (<= n 90))
-      (and (>= n 97) (<= n 122)))))
-
-(define
-  (hk-is-upper? c)
-  (let ((n (char->integer c))) (and (>= n 65) (<= n 90))))
-
-(define
-  (hk-is-lower? c)
-  (let ((n (char->integer c))) (and (>= n 97) (<= n 122))))
-
-(define
-  (hk-is-space? c)
-  (let
-    ((n (char->integer c)))
-    (or
-      (= n 32)
-      (= n 9)
-      (= n 10)
-      (= n 13)
-      (= n 12)
-      (= n 11))))
-
-(define hk-to-upper char-upcase)
-(define hk-to-lower char-downcase)
-
-;; digitToInt: '0'-'9' → 0-9, 'a'-'f'/'A'-'F' → 10-15
-(define
-  (hk-digit-to-int c)
-  (let
-    ((n (char->integer c)))
-    (cond
-      ((and (>= n 48) (<= n 57)) (- n 48))
-      ((and (>= n 65) (<= n 70)) (- n 55))
-      ((and (>= n 97) (<= n 102)) (- n 87))
-      (else (error (str "hk-digit-to-int: not a hex digit: " c))))))
-
-;; intToDigit: 0-15 → char
-(define
-  (hk-int-to-digit n)
-  (cond
-    ((and (>= n 0) (<= n 9))
-      (integer->char (+ n 48)))
-    ((and (>= n 10) (<= n 15))
-      (integer->char (+ n 87)))
-    (else (error (str "hk-int-to-digit: out of range: " n)))))
-
-;; ===========================================================================
-;; 5. Data.Set wrappers
-;; ===========================================================================
-
-(define (hk-set-empty) (make-set))
-(define hk-set? set?)
-(define hk-set-member? set-member?)
-
-(define (hk-set-insert x s) (begin (set-add! s x) s))
-
-(define (hk-set-delete x s) (begin (set-remove! s x) s))
-
-(define hk-set-union set-union)
-(define hk-set-intersection set-intersection)
-(define hk-set-difference set-difference)
-(define hk-set-from-list list->set)
-(define hk-set-to-list set->list)
-(define (hk-set-null? s) (= (len (set->list s)) 0))
-(define (hk-set-size s) (len (set->list s)))
-
-(define (hk-set-singleton x) (let ((s (make-set))) (set-add! s x) s))
-
-;; ===========================================================================
-;; 6. Data.List utilities
-;; ===========================================================================
-
-(define hk-head first)
-(define hk-tail rest)
-(define (hk-null? lst) (= (len lst) 0))
-(define hk-length len)
-
-(define
-  (hk-take n lst)
-  (if
-    (or (= n 0) (= (len lst) 0))
-    (list)
-    (cons (first lst) (hk-take (- n 1) (rest lst)))))
-
-(define
-  (hk-drop n lst)
-  (if
-    (or (= n 0) (= (len lst) 0))
-    lst
-    (hk-drop (- n 1) (rest lst))))
-
-(define
-  (hk-take-while pred lst)
-  (if
-    (or (= (len lst) 0) (not (pred (first lst))))
-    (list)
-    (cons (first lst) (hk-take-while pred (rest lst)))))
-
-(define
-  (hk-drop-while pred lst)
-  (if
-    (or (= (len lst) 0) (not (pred (first lst))))
-    lst
-    (hk-drop-while pred (rest lst))))
-
-(define
-  (hk-zip a b)
-  (if
-    (or (= (len a) 0) (= (len b) 0))
-    (list)
-    (cons (list (first a) (first b)) (hk-zip (rest a) (rest b)))))
-
-(define
-  (hk-zip-with f a b)
-  (if
-    (or (= (len a) 0) (= (len b) 0))
-    (list)
-    (cons (f (first a) (first b)) (hk-zip-with f (rest a) (rest b)))))
-
-(define
-  (hk-unzip pairs)
-  (list
-    (map (fn (p) (first p)) pairs)
-    (map (fn (p) (nth p 1)) pairs)))
-
-(define
-  (hk-elem x lst)
-  (cond
-    ((= (len lst) 0) false)
-    ((= x (first lst)) true)
-    (else (hk-elem x (rest lst)))))
-
-(define (hk-not-elem x lst) (not (hk-elem x lst)))
-
-(define
-  (hk-nub lst)
-  (letrec
-    ((go (fn (seen acc items) (if (= (len items) 0) (reverse acc) (let ((h (first items)) (t (rest items))) (if (hk-elem h seen) (go seen acc t) (go (cons h seen) (cons h acc) t)))))))
-    (go (list) (list) lst)))
-
-(define (hk-sum lst) (reduce + 0 lst))
-(define (hk-product lst) (reduce * 1 lst))
-
-(define
-  (hk-maximum lst)
-  (reduce (fn (a b) (if (> a b) a b)) (first lst) (rest lst)))
-
-(define
-  (hk-minimum lst)
-  (reduce (fn (a b) (if (< a b) a b)) (first lst) (rest lst)))
-
-(define (hk-concat lsts) (reduce append (list) lsts))
-
-(define (hk-concat-map f lst) (hk-concat (map f lst)))
-
-(define hk-sort sort)
-
-(define
-  (hk-span pred lst)
-  (list (hk-take-while pred lst) (hk-drop-while pred lst)))
-
-(define (hk-break pred lst) (hk-span (fn (x) (not (pred x))) lst))
-
-(define
-  (hk-foldl f acc lst)
-  (if
-    (= (len lst) 0)
-    acc
-    (hk-foldl f (f acc (first lst)) (rest lst))))
-
-(define
-  (hk-foldr f z lst)
-  (if
-    (= (len lst) 0)
-    z
-    (f (first lst) (hk-foldr f z (rest lst)))))
-
-(define
-  (hk-scanl f acc lst)
-  (if
-    (= (len lst) 0)
-    (list acc)
-    (cons acc (hk-scanl f (f acc (first lst)) (rest lst)))))
-
-(define
-  (hk-replicate n x)
-  (if (= n 0) (list) (cons x (hk-replicate (- n 1) x))))
-
-(define
-  (hk-intersperse sep lst)
-  (if
-    (or (= (len lst) 0) (= (len lst) 1))
-    lst
-    (cons (first lst) (cons sep (hk-intersperse sep (rest lst))))))
-
-;; ===========================================================================
-;; 7. Maybe / Either ADTs
-;; ===========================================================================
-
-(define hk-nothing {:_maybe true :_tag "nothing"})
-(define (hk-just x) {:_maybe true :value x :_tag "just"})
-(define (hk-is-nothing? m) (= (get m :_tag) "nothing"))
-(define (hk-is-just? m) (= (get m :_tag) "just"))
-(define (hk-from-just m) (get m :value))
-(define (hk-from-maybe def m) (if (hk-is-nothing? m) def (hk-from-just m)))
-(define
-  (hk-maybe def f m)
-  (if (hk-is-nothing? m) def (f (hk-from-just m))))
-
-(define (hk-left x) {:value x :_either true :_tag "left"})
-(define (hk-right x) {:value x :_either true :_tag "right"})
-(define (hk-is-left? e) (= (get e :_tag) "left"))
-(define (hk-is-right? e) (= (get e :_tag) "right"))
-(define (hk-from-left e) (get e :value))
-(define (hk-from-right e) (get e :value))
-(define
-  (hk-either f g e)
-  (if (hk-is-left? e) (f (hk-from-left e)) (g (hk-from-right e))))
-
-;; ===========================================================================
-;; 8. Tuples (lists — list->vector unreliable in sx_server)
-;; ===========================================================================
-
-(define (hk-pair a b) (list a b))
-(define hk-fst first)
-(define (hk-snd t) (nth t 1))
-
-(define (hk-triple a b c) (list a b c))
-(define hk-fst3 first)
-(define (hk-snd3 t) (nth t 1))
-(define (hk-thd3 t) (nth t 2))
-
-(define (hk-curry f) (fn (a) (fn (b) (f a b))))
-(define (hk-uncurry f) (fn (p) (f (hk-fst p) (hk-snd p))))
-
-;; ===========================================================================
-;; 9. String helpers (Data.List / Data.Char for strings)
-;; ===========================================================================
-
-;; words: split on whitespace
-(define
-  (hk-words s)
-  (letrec
-    ((slen (len s))
-      (skip-ws
+  hk-register-con!
   (fn
-          (i)
-          (if
-            (>= i slen)
-            (list)
-            (let
-              ((c (substring s i (+ i 1))))
-              (if
-                (or (= c " ") (= c "\t") (= c "\n"))
-                (skip-ws (+ i 1))
-                (collect-word i (+ i 1)))))))
-      (collect-word
+    (cname arity type-name)
+    (dict-set!
+      hk-constructors
+      cname
+      {:arity arity :type type-name})))
+
+(define hk-is-con? (fn (name) (has-key? hk-constructors name)))
+
+(define
+  hk-con-arity
   (fn
-          (start i)
+    (name)
     (if
-            (>= i slen)
-            (list (substring s start i))
-            (let
-              ((c (substring s i (+ i 1))))
-              (if
-                (or (= c " ") (= c "\t") (= c "\n"))
-                (cons (substring s start i) (skip-ws (+ i 1)))
-                (collect-word start (+ i 1))))))))
-    (skip-ws 0)))
+      (has-key? hk-constructors name)
+      (get (get hk-constructors name) "arity")
+      nil)))
 
-;; unwords: join with spaces
 (define
-  (hk-unwords lst)
-  (if
-    (= (len lst) 0)
-    ""
-    (reduce (fn (a b) (str a " " b)) (first lst) (rest lst))))
-
-;; lines: split on newline
-(define
-  (hk-lines s)
-  (letrec
-    ((slen (len s))
-      (go
+  hk-con-type
   (fn
-          (start i acc)
+    (name)
     (if
-            (>= i slen)
-            (reverse (cons (substring s start i) acc))
-            (if
-              (= (substring s i (+ i 1)) "\n")
-              (go
-                (+ i 1)
-                (+ i 1)
-                (cons (substring s start i) acc))
-              (go start (+ i 1) acc))))))
-    (if (= slen 0) (list) (go 0 0 (list)))))
+      (has-key? hk-constructors name)
+      (get (get hk-constructors name) "type")
+      nil)))
 
-;; unlines: join, each with trailing newline
-(define (hk-unlines lst) (reduce (fn (a b) (str a b "\n")) "" lst))
+(define hk-con-names (fn () (keys hk-constructors)))
 
-;; isPrefixOf
+;; ── Registration from AST ────────────────────────────────────
+;; (:data NAME TVARS ((:con-def CNAME FIELDS) …))
 (define
-  (hk-is-prefix-of pre s)
-  (and (<= (len pre) (len s)) (= pre (substring s 0 (len pre)))))
-
-;; isSuffixOf
-(define
-  (hk-is-suffix-of suf s)
+  hk-register-data!
+  (fn
+    (data-node)
     (let
-    ((sl (len suf)) (tl (len s)))
-    (and (<= sl tl) (= suf (substring s (- tl sl) tl)))))
+      ((type-name (nth data-node 1))
+        (cons-list (nth data-node 3)))
+      (for-each
+        (fn
+          (cd)
+          (hk-register-con!
+            (nth cd 1)
+            (len (nth cd 2))
+            type-name))
+        cons-list))))
 
-;; isInfixOf — linear scan
+;; (:newtype NAME TVARS CNAME FIELD)
 (define
-  (hk-is-infix-of pat s)
-  (let
-    ((plen (len pat)) (slen (len s)))
-    (letrec
-      ((go (fn (i) (if (> (+ i plen) slen) false (if (= pat (substring s i (+ i plen))) true (go (+ i 1)))))))
-      (if (= plen 0) true (go 0)))))
-
-;; ===========================================================================
-;; 10. Show helper
-;; ===========================================================================
+  hk-register-newtype!
+  (fn
+    (nt-node)
+    (hk-register-con!
+      (nth nt-node 3)
+      1
+      (nth nt-node 1))))
 
+;; Walk a decls list, registering every `data` / `newtype` decl.
 (define
-  (hk-show x)
+  hk-register-decls!
+  (fn
+    (decls)
+    (for-each
+      (fn
+        (d)
         (cond
-    ((= x nil) "Nothing")
-    ((= x true) "True")
-    ((= x false) "False")
-    ((hk-rational? x) (hk-show-rational x))
-    ((integer? x) (str x))
-    ((float? x) (str x))
-    ((= (type-of x) "string") (str "\"" x "\""))
-    ((= (type-of x) "char") (str "'" (str x) "'"))
-    ((list? x)
-      (str
-        "["
-        (if
-          (= (len x) 0)
-          ""
-          (reduce
-            (fn (a b) (str a "," (hk-show b)))
-            (hk-show (first x))
-            (rest x)))
-        "]"))
-    (else (str x))))
+          ((and
+              (list? d)
+              (not (empty? d))
+              (= (first d) "data"))
+            (hk-register-data! d))
+          ((and
+              (list? d)
+              (not (empty? d))
+              (= (first d) "newtype"))
+            (hk-register-newtype! d))
+          (:else nil)))
+      decls)))
+
+(define
+  hk-register-program!
+  (fn
+    (ast)
+    (cond
+      ((nil? ast) nil)
+      ((not (list? ast)) nil)
+      ((empty? ast) nil)
+      ((= (first ast) "program")
+        (hk-register-decls! (nth ast 1)))
+      ((= (first ast) "module")
+        (hk-register-decls! (nth ast 4)))
+      (:else nil))))
+
+;; Convenience: source → AST → desugar → register.
+(define
+  hk-load-source!
+  (fn (src) (hk-register-program! (hk-core src))))
+
+;; ── Built-in constructors pre-registered ─────────────────────
+;; Bool — used implicitly by `if`, comparison operators.
+(hk-register-con! "True" 0 "Bool")
+(hk-register-con! "False" 0 "Bool")
+;; List — used by list literals, range syntax, and cons operator.
+(hk-register-con! "[]" 0 "List")
+(hk-register-con! ":" 2 "List")
+;; Unit — produced by empty parens `()`.
+(hk-register-con! "()" 0 "Unit")
+;; Standard Prelude types — pre-registered so expression-level
+;; programs can use them without a `data` decl.
+(hk-register-con! "Nothing" 0 "Maybe")
+(hk-register-con! "Just"    1 "Maybe")
+(hk-register-con! "Left"    1 "Either")
+(hk-register-con! "Right"   1 "Either")
+(hk-register-con! "LT" 0 "Ordering")
+(hk-register-con! "EQ" 0 "Ordering")
+(hk-register-con! "GT" 0 "Ordering")

lib/haskell/scoreboard.json

@@ -0,0 +1,25 @@
+{
+  "date": "2026-05-06",
+  "total_pass": 156,
+  "total_fail": 0,
+  "programs": {
+    "fib": {"pass": 2, "fail": 0},
+    "sieve": {"pass": 2, "fail": 0},
+    "quicksort": {"pass": 5, "fail": 0},
+    "nqueens": {"pass": 2, "fail": 0},
+    "calculator": {"pass": 5, "fail": 0},
+    "collatz": {"pass": 11, "fail": 0},
+    "palindrome": {"pass": 8, "fail": 0},
+    "maybe": {"pass": 12, "fail": 0},
+    "fizzbuzz": {"pass": 12, "fail": 0},
+    "anagram": {"pass": 9, "fail": 0},
+    "roman": {"pass": 14, "fail": 0},
+    "binary": {"pass": 12, "fail": 0},
+    "either": {"pass": 12, "fail": 0},
+    "primes": {"pass": 12, "fail": 0},
+    "zipwith": {"pass": 9, "fail": 0},
+    "matrix": {"pass": 8, "fail": 0},
+    "wordcount": {"pass": 7, "fail": 0},
+    "powers": {"pass": 14, "fail": 0}
+  }
+}

lib/haskell/scoreboard.md

@@ -0,0 +1,25 @@
+# Haskell-on-SX Scoreboard
+
+Updated 2026-05-06 · Phase 6 (prelude extras + 18 programs)
+
+| Program | Tests | Status |
+|---------|-------|--------|
+| fib.hs | 2/2 | ✓ |
+| sieve.hs | 2/2 | ✓ |
+| quicksort.hs | 5/5 | ✓ |
+| nqueens.hs | 2/2 | ✓ |
+| calculator.hs | 5/5 | ✓ |
+| collatz.hs | 11/11 | ✓ |
+| palindrome.hs | 8/8 | ✓ |
+| maybe.hs | 12/12 | ✓ |
+| fizzbuzz.hs | 12/12 | ✓ |
+| anagram.hs | 9/9 | ✓ |
+| roman.hs | 14/14 | ✓ |
+| binary.hs | 12/12 | ✓ |
+| either.hs | 12/12 | ✓ |
+| primes.hs | 12/12 | ✓ |
+| zipwith.hs | 9/9 | ✓ |
+| matrix.hs | 8/8 | ✓ |
+| wordcount.hs | 7/7 | ✓ |
+| powers.hs | 14/14 | ✓ |
+| **Total** | **156/156** | **18/18 programs** |

lib/haskell/test.sh

@@ -14,7 +14,7 @@ cd "$(git rev-parse --show-toplevel)"
 SX_SERVER="hosts/ocaml/_build/default/bin/sx_server.exe"
 if [ ! -x "$SX_SERVER" ]; then
   # Fall back to the main-repo build if we're in a worktree.
-  MAIN_ROOT=$(git worktree list | head -1 | awk '{print $1}')
+  MAIN_ROOT=$(git worktree list | awk 'NR==1{print $1}')
   if [ -x "$MAIN_ROOT/$SX_SERVER" ]; then
     SX_SERVER="$MAIN_ROOT/$SX_SERVER"
   else
@@ -42,25 +42,35 @@ FAILED_FILES=()
 
 for FILE in "${FILES[@]}"; do
   [ -f "$FILE" ] || { echo "skip $FILE (not found)"; continue; }
+  # Load infer.sx only for infer/typecheck test files (it adds ~6s overhead).
+  INFER_LOAD=""
+  case "$FILE" in *infer*|*typecheck*) INFER_LOAD='(load "lib/haskell/infer.sx")' ;; esac
   TMPFILE=$(mktemp)
   cat > "$TMPFILE" <<EPOCHS
 (epoch 1)
 (load "lib/haskell/tokenizer.sx")
+(load "lib/haskell/layout.sx")
+(load "lib/haskell/parser.sx")
+(load "lib/haskell/desugar.sx")
 (load "lib/haskell/runtime.sx")
+(load "lib/haskell/match.sx")
+(load "lib/haskell/eval.sx")
+$INFER_LOAD
+(load "lib/haskell/testlib.sx")
 (epoch 2)
 (load "$FILE")
 (epoch 3)
 (eval "(list hk-test-pass hk-test-fail)")
 EPOCHS
 
-  OUTPUT=$(timeout 60 "$SX_SERVER" < "$TMPFILE" 2>&1 || true)
+  OUTPUT=$(timeout 360 "$SX_SERVER" < "$TMPFILE" 2>&1 || true)
   rm -f "$TMPFILE"
 
   # Output format: either "(ok 3 (P F))" on one line (short result) or
   # "(ok-len 3 N)\n(P F)" where the value appears on the following line.
   LINE=$(echo "$OUTPUT" | awk '/^\(ok-len 3 / {getline; print; exit}')
   if [ -z "$LINE" ]; then
-    LINE=$(echo "$OUTPUT" | grep -E '^\(ok 3 \([0-9]+ [0-9]+\)\)' | tail -1 \
+    LINE=$(echo "$OUTPUT" | { grep -E '^\(ok 3 \([0-9]+ [0-9]+\)\)' || true; } | tail -1 \
             | sed -E 's/^\(ok 3 //; s/\)$//')
   fi
   if [ -z "$LINE" ]; then
@@ -82,13 +92,20 @@ EPOCHS
     cat > "$TMPFILE2" <<EPOCHS
 (epoch 1)
 (load "lib/haskell/tokenizer.sx")
+(load "lib/haskell/layout.sx")
+(load "lib/haskell/parser.sx")
+(load "lib/haskell/desugar.sx")
 (load "lib/haskell/runtime.sx")
+(load "lib/haskell/match.sx")
+(load "lib/haskell/eval.sx")
+$INFER_LOAD
+(load "lib/haskell/testlib.sx")
 (epoch 2)
 (load "$FILE")
 (epoch 3)
 (eval "(map (fn (f) (get f \"name\")) hk-test-fails)")
 EPOCHS
-    FAILS=$(timeout 60 "$SX_SERVER" < "$TMPFILE2" 2>&1 | grep -E '^\(ok 3 ' || true)
+    FAILS=$(timeout 360 "$SX_SERVER" < "$TMPFILE2" 2>&1 | grep -E '^\(ok 3 ' || true)
     rm -f "$TMPFILE2"
     echo "    $FAILS"
   elif [ "$VERBOSE" = "1" ]; then

lib/haskell/testlib.sx

@@ -0,0 +1,58 @@
+;; Shared test harness for Haskell-on-SX tests.
+;; Each test file expects hk-test / hk-deep=? / counters to already be bound.
+
+(define
+  hk-deep=?
+  (fn
+    (a b)
+    (cond
+      ((= a b) true)
+      ((and (dict? a) (dict? b))
+        (let
+          ((ak (keys a)) (bk (keys b)))
+          (if
+            (not (= (len ak) (len bk)))
+            false
+            (every?
+              (fn
+                (k)
+                (and (has-key? b k) (hk-deep=? (get a k) (get b k))))
+              ak))))
+      ((and (list? a) (list? b))
+        (if
+          (not (= (len a) (len b)))
+          false
+          (let
+            ((i 0) (ok true))
+            (define
+              hk-de-loop
+              (fn
+                ()
+                (when
+                  (and ok (< i (len a)))
+                  (do
+                    (when
+                      (not (hk-deep=? (nth a i) (nth b i)))
+                      (set! ok false))
+                    (set! i (+ i 1))
+                    (hk-de-loop)))))
+            (hk-de-loop)
+            ok)))
+      (:else false))))
+
+(define hk-test-pass 0)
+(define hk-test-fail 0)
+(define hk-test-fails (list))
+
+(define
+  hk-test
+  (fn
+    (name actual expected)
+    (if
+      (hk-deep=? actual expected)
+      (set! hk-test-pass (+ hk-test-pass 1))
+      (do
+        (set! hk-test-fail (+ hk-test-fail 1))
+        (append!
+          hk-test-fails
+          {:actual actual :expected expected :name name})))))

lib/haskell/tests/class.sx

@@ -0,0 +1,60 @@
+;; class.sx — tests for class/instance parsing and evaluation.
+
+(define prog-class1 (hk-core "class MyEq a where\n  myEq :: a -> a -> Bool"))
+(define prog-inst1 (hk-core "instance MyEq Int where\n  myEq x y = x == y"))
+
+;; ─── class-decl AST ───────────────────────────────────────────────────────────
+(define cd1 (first (nth prog-class1 1)))
+(hk-test "class-decl tag" (first cd1) "class-decl")
+(hk-test "class-decl name" (nth cd1 1) "MyEq")
+(hk-test "class-decl tvar" (nth cd1 2) "a")
+(hk-test "class-decl methods" (len (nth cd1 3)) 1)
+
+;; ─── instance-decl AST ────────────────────────────────────────────────────────
+(define id1 (first (nth prog-inst1 1)))
+(hk-test "instance-decl tag" (first id1) "instance-decl")
+(hk-test "instance-decl class" (nth id1 1) "MyEq")
+(hk-test "instance-decl type tag" (first (nth id1 2)) "t-con")
+(hk-test "instance-decl type name" (nth (nth id1 2) 1) "Int")
+(hk-test "instance-decl method count" (len (nth id1 3)) 1)
+
+;; ─── eval: instance dict is built ────────────────────────────────────────────
+(define
+  prog-full
+  (hk-core
+    "class MyEq a where\n  myEq :: a -> a -> Bool\ninstance MyEq Int where\n  myEq x y = x == y"))
+(define env-full (hk-eval-program prog-full))
+
+(hk-test "instance dict in env" (has-key? env-full "dictMyEq_Int") true)
+
+(hk-test
+  "instance dict has method"
+  (has-key? (get env-full "dictMyEq_Int") "myEq")
+  true)
+
+(hk-test
+  "dispatch: single-arg method works"
+  (hk-deep-force
+    (hk-run
+      "class Describable a where\n  describe :: a -> String\ninstance Describable Int where\n  describe x = \"an integer\"\nmain = describe 42"))
+  "an integer")
+
+(hk-test
+  "dispatch: second instance (Bool)"
+  (hk-deep-force
+    (hk-run
+      "class Describable a where\n  describe :: a -> String\ninstance Describable Bool where\n  describe x = \"a boolean\"\ninstance Describable Int where\n  describe x = \"an integer\"\nmain = describe True"))
+  "a boolean")
+
+(hk-test
+  "dispatch: error on unknown instance"
+  (guard
+    (e (true (>= (index-of e "No instance") 0)))
+    (begin
+      (hk-deep-force
+        (hk-run
+          "class Describable a where\n  describe :: a -> String\nmain = describe 42"))
+      false))
+  true)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/deriving.sx

@@ -0,0 +1,84 @@
+;; deriving.sx — tests for deriving (Eq, Show) on ADTs.
+
+;; ─── Show ────────────────────────────────────────────────────────────────────
+
+(hk-test
+  "deriving Show: nullary constructor"
+  (hk-deep-force
+    (hk-run "data Color = Red | Green | Blue deriving (Show)\nmain = show Red"))
+  "Red")
+
+(hk-test
+  "deriving Show: constructor with arg"
+  (hk-deep-force
+    (hk-run "data Wrapper = Wrap Int deriving (Show)\nmain = show (Wrap 42)"))
+  "(Wrap 42)")
+
+(hk-test
+  "deriving Show: nested constructors"
+  (hk-deep-force
+    (hk-run
+      "data Tree = Leaf | Node Int Tree Tree deriving (Show)\nmain = show (Node 1 Leaf Leaf)"))
+  "(Node 1 Leaf Leaf)")
+
+(hk-test
+  "deriving Show: second constructor"
+  (hk-deep-force
+    (hk-run
+      "data Color = Red | Green | Blue deriving (Show)\nmain = show Green"))
+  "Green")
+
+;; ─── Eq ──────────────────────────────────────────────────────────────────────
+
+(hk-test
+  "deriving Eq: same constructor"
+  (hk-deep-force
+    (hk-run
+      "data Color = Red | Green | Blue deriving (Eq)\nmain = show (Red == Red)"))
+  "True")
+
+(hk-test
+  "deriving Eq: different constructors"
+  (hk-deep-force
+    (hk-run
+      "data Color = Red | Green | Blue deriving (Eq)\nmain = show (Red == Blue)"))
+  "False")
+
+(hk-test
+  "deriving Eq: /= same"
+  (hk-deep-force
+    (hk-run
+      "data Color = Red | Green | Blue deriving (Eq)\nmain = show (Red /= Red)"))
+  "False")
+
+(hk-test
+  "deriving Eq: /= different"
+  (hk-deep-force
+    (hk-run
+      "data Color = Red | Green | Blue deriving (Eq)\nmain = show (Red /= Blue)"))
+  "True")
+
+;; ─── combined Eq + Show ───────────────────────────────────────────────────────
+
+(hk-test
+  "deriving Eq Show: combined in parens"
+  (hk-deep-force
+    (hk-run
+      "data Shape = Circle Int | Square Int deriving (Eq, Show)\nmain = show (Circle 5)"))
+  "(Circle 5)")
+
+(hk-test
+  "deriving Eq Show: eq on constructor with arg"
+  (hk-deep-force
+    (hk-run
+      "data Shape = Circle Int | Square Int deriving (Eq, Show)\nmain = show (Circle 3 == Circle 3)"))
+  "True")
+
+(hk-test
+  "deriving Eq Show: different constructors with args"
+  (hk-deep-force
+    (hk-run
+      "data Shape = Circle Int | Square Int deriving (Eq, Show)\nmain = show (Circle 3 == Square 3)"))
+  "False")
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/desugar.sx

@@ -0,0 +1,305 @@
+;; Desugar tests — surface AST → core AST.
+;;   :guarded   →  nested :if
+;;   :where     →  :let
+;;   :list-comp →  concatMap-based tree
+
+(define
+  hk-prog
+  (fn (&rest decls) (list :program decls)))
+
+;; ── Guards → if ──
+(hk-test
+  "two-way guarded rhs"
+  (hk-desugar (hk-parse-top "abs x | x < 0 = - x\n      | otherwise = x"))
+  (hk-prog
+    (list
+      :fun-clause
+      "abs"
+      (list (list :p-var "x"))
+      (list
+        :if
+        (list :op "<" (list :var "x") (list :int 0))
+        (list :neg (list :var "x"))
+        (list
+          :if
+          (list :var "otherwise")
+          (list :var "x")
+          (list
+            :app
+            (list :var "error")
+            (list :string "Non-exhaustive guards")))))))
+
+(hk-test
+  "three-way guarded rhs"
+  (hk-desugar
+    (hk-parse-top "sign n | n > 0 = 1\n       | n < 0 = -1\n       | otherwise = 0"))
+  (hk-prog
+    (list
+      :fun-clause
+      "sign"
+      (list (list :p-var "n"))
+      (list
+        :if
+        (list :op ">" (list :var "n") (list :int 0))
+        (list :int 1)
+        (list
+          :if
+          (list :op "<" (list :var "n") (list :int 0))
+          (list :neg (list :int 1))
+          (list
+            :if
+            (list :var "otherwise")
+            (list :int 0)
+            (list
+              :app
+              (list :var "error")
+              (list :string "Non-exhaustive guards"))))))))
+
+(hk-test
+  "case-alt guards desugared too"
+  (hk-desugar
+    (hk-parse "case x of\n  Just y | y > 0 -> y\n         | otherwise -> 0\n  Nothing -> -1"))
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list :p-con "Just" (list (list :p-var "y")))
+        (list
+          :if
+          (list :op ">" (list :var "y") (list :int 0))
+          (list :var "y")
+          (list
+            :if
+            (list :var "otherwise")
+            (list :int 0)
+            (list
+              :app
+              (list :var "error")
+              (list :string "Non-exhaustive guards")))))
+      (list
+        :alt
+        (list :p-con "Nothing" (list))
+        (list :neg (list :int 1))))))
+
+;; ── Where → let ──
+(hk-test
+  "where with single binding"
+  (hk-desugar (hk-parse-top "f x = y\n  where y = x + 1"))
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list
+        :let
+        (list
+          (list
+            :fun-clause
+            "y"
+            (list)
+            (list :op "+" (list :var "x") (list :int 1))))
+        (list :var "y")))))
+
+(hk-test
+  "where with two bindings"
+  (hk-desugar
+    (hk-parse-top "f x = y + z\n  where y = x + 1\n        z = x - 1"))
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list
+        :let
+        (list
+          (list
+            :fun-clause
+            "y"
+            (list)
+            (list :op "+" (list :var "x") (list :int 1)))
+          (list
+            :fun-clause
+            "z"
+            (list)
+            (list :op "-" (list :var "x") (list :int 1))))
+        (list :op "+" (list :var "y") (list :var "z"))))))
+
+(hk-test
+  "guards + where — guarded body inside let"
+  (hk-desugar
+    (hk-parse-top "f x | x > 0 = y\n    | otherwise = 0\n  where y = 99"))
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list
+        :let
+        (list (list :fun-clause "y" (list) (list :int 99)))
+        (list
+          :if
+          (list :op ">" (list :var "x") (list :int 0))
+          (list :var "y")
+          (list
+            :if
+            (list :var "otherwise")
+            (list :int 0)
+            (list
+              :app
+              (list :var "error")
+              (list :string "Non-exhaustive guards"))))))))
+
+;; ── List comprehensions → concatMap / if / let ──
+(hk-test
+  "list-comp: single generator"
+  (hk-core-expr "[x | x <- xs]")
+  (list
+    :app
+    (list
+      :app
+      (list :var "concatMap")
+      (list
+        :lambda
+        (list (list :p-var "x"))
+        (list :list (list (list :var "x")))))
+    (list :var "xs")))
+
+(hk-test
+  "list-comp: generator then guard"
+  (hk-core-expr "[x * 2 | x <- xs, x > 0]")
+  (list
+    :app
+    (list
+      :app
+      (list :var "concatMap")
+      (list
+        :lambda
+        (list (list :p-var "x"))
+        (list
+          :if
+          (list :op ">" (list :var "x") (list :int 0))
+          (list
+            :list
+            (list (list :op "*" (list :var "x") (list :int 2))))
+          (list :list (list)))))
+    (list :var "xs")))
+
+(hk-test
+  "list-comp: generator then let"
+  (hk-core-expr "[y | x <- xs, let y = x + 1]")
+  (list
+    :app
+    (list
+      :app
+      (list :var "concatMap")
+      (list
+        :lambda
+        (list (list :p-var "x"))
+        (list
+          :let
+          (list
+            (list
+              :bind
+              (list :p-var "y")
+              (list :op "+" (list :var "x") (list :int 1))))
+          (list :list (list (list :var "y"))))))
+    (list :var "xs")))
+
+(hk-test
+  "list-comp: two generators (nested concatMap)"
+  (hk-core-expr "[(x, y) | x <- xs, y <- ys]")
+  (list
+    :app
+    (list
+      :app
+      (list :var "concatMap")
+      (list
+        :lambda
+        (list (list :p-var "x"))
+        (list
+          :app
+          (list
+            :app
+            (list :var "concatMap")
+            (list
+              :lambda
+              (list (list :p-var "y"))
+              (list
+                :list
+                (list
+                  (list
+                    :tuple
+                    (list (list :var "x") (list :var "y")))))))
+          (list :var "ys"))))
+    (list :var "xs")))
+
+;; ── Pass-through cases ──
+(hk-test
+  "plain int literal unchanged"
+  (hk-core-expr "42")
+  (list :int 42))
+
+(hk-test
+  "lambda + if passes through"
+  (hk-core-expr "\\x -> if x > 0 then x else - x")
+  (list
+    :lambda
+    (list (list :p-var "x"))
+    (list
+      :if
+      (list :op ">" (list :var "x") (list :int 0))
+      (list :var "x")
+      (list :neg (list :var "x")))))
+
+(hk-test
+  "simple fun-clause (no guards/where) passes through"
+  (hk-desugar (hk-parse-top "id x = x"))
+  (hk-prog
+    (list
+      :fun-clause
+      "id"
+      (list (list :p-var "x"))
+      (list :var "x"))))
+
+(hk-test
+  "data decl passes through"
+  (hk-desugar (hk-parse-top "data Maybe a = Nothing | Just a"))
+  (hk-prog
+    (list
+      :data
+      "Maybe"
+      (list "a")
+      (list
+        (list :con-def "Nothing" (list))
+        (list :con-def "Just" (list (list :t-var "a")))))))
+
+(hk-test
+  "module header passes through, body desugared"
+  (hk-desugar
+    (hk-parse-top "module M where\nf x | x > 0 = 1\n    | otherwise = 0"))
+  (list
+    :module
+    "M"
+    nil
+    (list)
+    (list
+      (list
+        :fun-clause
+        "f"
+        (list (list :p-var "x"))
+        (list
+          :if
+          (list :op ">" (list :var "x") (list :int 0))
+          (list :int 1)
+          (list
+            :if
+            (list :var "otherwise")
+            (list :int 0)
+            (list
+              :app
+              (list :var "error")
+              (list :string "Non-exhaustive guards"))))))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/do-io.sx

@@ -0,0 +1,117 @@
+;; do-notation + stub IO monad. Desugaring is per Haskell 98 §3.14:
+;;   do { e ; ss }      = e >> do { ss }
+;;   do { p <- e ; ss } = e >>= \p -> do { ss }
+;;   do { let ds ; ss } = let ds in do { ss }
+;;   do { e }           = e
+;; The IO type is just `("IO" payload)` for now — no real side
+;; effects yet. `return`, `>>=`, `>>` are built-ins.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+;; ── Single-statement do ──
+(hk-test
+  "do with a single expression"
+  (hk-eval-expr-source "do { return 5 }")
+  (list "IO" 5))
+
+(hk-test
+  "return wraps any expression"
+  (hk-eval-expr-source "return (1 + 2 * 3)")
+  (list "IO" 7))
+
+;; ── Bind threads results ──
+(hk-test
+  "single bind"
+  (hk-eval-expr-source
+    "do { x <- return 5 ; return (x + 1) }")
+  (list "IO" 6))
+
+(hk-test
+  "two binds"
+  (hk-eval-expr-source
+    "do\n  x <- return 5\n  y <- return 7\n  return (x + y)")
+  (list "IO" 12))
+
+(hk-test
+  "three binds — accumulating"
+  (hk-eval-expr-source
+    "do\n  a <- return 1\n  b <- return 2\n  c <- return 3\n  return (a + b + c)")
+  (list "IO" 6))
+
+;; ── Mixing >> and >>= ──
+(hk-test
+  ">> sequencing — last wins"
+  (hk-eval-expr-source
+    "do\n  return 1\n  return 2\n  return 3")
+  (list "IO" 3))
+
+(hk-test
+  ">> then >>= — last bind wins"
+  (hk-eval-expr-source
+    "do\n  return 99\n  x <- return 5\n  return x")
+  (list "IO" 5))
+
+;; ── do-let ──
+(hk-test
+  "do-let single binding"
+  (hk-eval-expr-source
+    "do\n  let x = 3\n  return (x * 2)")
+  (list "IO" 6))
+
+(hk-test
+  "do-let multi-bind, used after"
+  (hk-eval-expr-source
+    "do\n  let x = 4\n      y = 5\n  return (x * y)")
+  (list "IO" 20))
+
+(hk-test
+  "do-let interleaved with bind"
+  (hk-eval-expr-source
+    "do\n  x <- return 10\n  let y = x + 1\n  return (x * y)")
+  (list "IO" 110))
+
+;; ── Bind + pattern ──
+(hk-test
+  "bind to constructor pattern"
+  (hk-eval-expr-source
+    "do\n  Just x <- return (Just 7)\n  return (x + 100)")
+  (list "IO" 107))
+
+(hk-test
+  "bind to tuple pattern"
+  (hk-eval-expr-source
+    "do\n  (a, b) <- return (3, 4)\n  return (a * b)")
+  (list "IO" 12))
+
+;; ── User-defined IO functions ──
+(hk-test
+  "do inside top-level fun"
+  (hk-prog-val
+    "addM x y = do\n  a <- return x\n  b <- return y\n  return (a + b)\nresult = addM 5 6"
+    "result")
+  (list "IO" 11))
+
+(hk-test
+  "nested do"
+  (hk-eval-expr-source
+    "do\n  x <- do { y <- return 3 ; return (y + 1) }\n  return (x * 2)")
+  (list "IO" 8))
+
+;; ── (>>=) and (>>) used directly as functions ──
+(hk-test
+  ">>= used directly"
+  (hk-eval-expr-source
+    "(return 4) >>= (\\x -> return (x + 100))")
+  (list "IO" 104))
+
+(hk-test
+  ">> used directly"
+  (hk-eval-expr-source
+    "(return 1) >> (return 2)")
+  (list "IO" 2))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/eval.sx

@@ -0,0 +1,278 @@
+;; Strict evaluator tests. Each test parses, desugars, and evaluates
+;; either an expression (hk-eval-expr-source) or a full program
+;; (hk-eval-program → look up a named value).
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+;; ── Literals ──
+(hk-test "int literal" (hk-eval-expr-source "42") 42)
+(hk-test "float literal" (hk-eval-expr-source "3.14") 3.14)
+(hk-test "string literal" (hk-eval-expr-source "\"hi\"") "hi")
+(hk-test "char literal" (hk-eval-expr-source "'a'") "a")
+(hk-test "negative literal" (hk-eval-expr-source "- 5") -5)
+
+;; ── Arithmetic ──
+(hk-test "addition" (hk-eval-expr-source "1 + 2") 3)
+(hk-test
+  "precedence"
+  (hk-eval-expr-source "1 + 2 * 3")
+  7)
+(hk-test
+  "parens override precedence"
+  (hk-eval-expr-source "(1 + 2) * 3")
+  9)
+(hk-test
+  "subtraction left-assoc"
+  (hk-eval-expr-source "10 - 3 - 2")
+  5)
+
+;; ── Comparison + Bool ──
+(hk-test
+  "less than is True"
+  (hk-eval-expr-source "3 < 5")
+  (list "True"))
+(hk-test
+  "equality is False"
+  (hk-eval-expr-source "1 == 2")
+  (list "False"))
+(hk-test
+  "&& shortcuts"
+  (hk-eval-expr-source "(1 == 1) && (2 == 2)")
+  (list "True"))
+
+;; ── if / otherwise ──
+(hk-test
+  "if True"
+  (hk-eval-expr-source "if True then 1 else 2")
+  1)
+(hk-test
+  "if comparison branch"
+  (hk-eval-expr-source "if 5 > 3 then \"yes\" else \"no\"")
+  "yes")
+(hk-test "otherwise is True" (hk-eval-expr-source "otherwise") (list "True"))
+
+;; ── let ──
+(hk-test
+  "let single binding"
+  (hk-eval-expr-source "let x = 5 in x + 1")
+  6)
+(hk-test
+  "let two bindings"
+  (hk-eval-expr-source "let x = 1; y = 2 in x + y")
+  3)
+(hk-test
+  "let recursive: factorial 5"
+  (hk-eval-expr-source
+    "let f n = if n == 0 then 1 else n * f (n - 1) in f 5")
+  120)
+
+;; ── Lambdas ──
+(hk-test
+  "lambda apply"
+  (hk-eval-expr-source "(\\x -> x + 1) 5")
+  6)
+(hk-test
+  "lambda multi-arg"
+  (hk-eval-expr-source "(\\x y -> x * y) 3 4")
+  12)
+(hk-test
+  "lambda with constructor pattern"
+  (hk-eval-expr-source "(\\(Just x) -> x + 1) (Just 7)")
+  8)
+
+;; ── Constructors ──
+(hk-test
+  "0-arity constructor"
+  (hk-eval-expr-source "Nothing")
+  (list "Nothing"))
+(hk-test
+  "1-arity constructor applied"
+  (hk-eval-expr-source "Just 5")
+  (list "Just" 5))
+(hk-test
+  "True / False as bools"
+  (hk-eval-expr-source "True")
+  (list "True"))
+
+;; ── case ──
+(hk-test
+  "case Just"
+  (hk-eval-expr-source
+    "case Just 7 of Just x -> x ; Nothing -> 0")
+  7)
+(hk-test
+  "case Nothing"
+  (hk-eval-expr-source
+    "case Nothing of Just x -> x ; Nothing -> 99")
+  99)
+(hk-test
+  "case literal pattern"
+  (hk-eval-expr-source
+    "case 0 of 0 -> \"zero\" ; n -> \"other\"")
+  "zero")
+(hk-test
+  "case tuple"
+  (hk-eval-expr-source
+    "case (1, 2) of (a, b) -> a + b")
+  3)
+(hk-test
+  "case wildcard fallback"
+  (hk-eval-expr-source
+    "case 5 of 0 -> \"z\" ; _ -> \"nz\"")
+  "nz")
+
+;; ── List literals + cons ──
+(hk-test
+  "list literal as cons spine"
+  (hk-eval-expr-source "[1, 2, 3]")
+  (list ":" 1 (list ":" 2 (list ":" 3 (list "[]")))))
+(hk-test
+  "empty list literal"
+  (hk-eval-expr-source "[]")
+  (list "[]"))
+(hk-test
+  "cons via :"
+  (hk-eval-expr-source "1 : []")
+  (list ":" 1 (list "[]")))
+(hk-test
+  "++ concatenates lists"
+  (hk-eval-expr-source "[1, 2] ++ [3]")
+  (list ":" 1 (list ":" 2 (list ":" 3 (list "[]")))))
+
+;; ── Tuples ──
+(hk-test
+  "2-tuple"
+  (hk-eval-expr-source "(1, 2)")
+  (list "Tuple" 1 2))
+(hk-test
+  "3-tuple"
+  (hk-eval-expr-source "(\"a\", 5, True)")
+  (list "Tuple" "a" 5 (list "True")))
+
+;; ── Sections ──
+(hk-test
+  "right section (+ 1) applied"
+  (hk-eval-expr-source "(+ 1) 5")
+  6)
+(hk-test
+  "left section (10 -) applied"
+  (hk-eval-expr-source "(10 -) 4")
+  6)
+
+;; ── Multi-clause top-level functions ──
+(hk-test
+  "multi-clause: factorial"
+  (hk-prog-val
+    "fact 0 = 1\nfact n = n * fact (n - 1)\nresult = fact 6"
+    "result")
+  720)
+
+(hk-test
+  "multi-clause: list length via cons pattern"
+  (hk-prog-val
+    "len [] = 0\nlen (x:xs) = 1 + len xs\nresult = len [10, 20, 30, 40]"
+    "result")
+  4)
+
+(hk-test
+  "multi-clause: Maybe handler"
+  (hk-prog-val
+    "fromMaybe d Nothing = d\nfromMaybe _ (Just x) = x\nresult = fromMaybe 0 (Just 9)"
+    "result")
+  9)
+
+(hk-test
+  "multi-clause: Maybe with default"
+  (hk-prog-val
+    "fromMaybe d Nothing = d\nfromMaybe _ (Just x) = x\nresult = fromMaybe 0 Nothing"
+    "result")
+  0)
+
+;; ── User-defined data and matching ──
+(hk-test
+  "custom data with pattern match"
+  (hk-prog-val
+    "data Color = Red | Green | Blue\nname Red = \"red\"\nname Green = \"green\"\nname Blue = \"blue\"\nresult = name Green"
+    "result")
+  "green")
+
+(hk-test
+  "custom binary tree height"
+  (hk-prog-val
+    "data Tree = Leaf | Node Tree Tree\nh Leaf = 0\nh (Node l r) = 1 + max (h l) (h r)\nmax a b = if a > b then a else b\nresult = h (Node (Node Leaf Leaf) Leaf)"
+    "result")
+  2)
+
+;; ── Currying ──
+(hk-test
+  "partial application"
+  (hk-prog-val
+    "add x y = x + y\nadd5 = add 5\nresult = add5 7"
+    "result")
+  12)
+
+;; ── Higher-order ──
+(hk-test
+  "higher-order: function as arg"
+  (hk-prog-val
+    "twice f x = f (f x)\ninc x = x + 1\nresult = twice inc 10"
+    "result")
+  12)
+
+;; ── Error built-in ──
+(hk-test
+  "error short-circuits via if"
+  (hk-eval-expr-source
+    "if True then 1 else error \"unreachable\"")
+  1)
+
+;; ── Laziness: app args evaluate only when forced ──
+(hk-test
+  "second arg never forced"
+  (hk-eval-expr-source
+    "(\\x y -> x) 1 (error \"never\")")
+  1)
+
+(hk-test
+  "first arg never forced"
+  (hk-eval-expr-source
+    "(\\x y -> y) (error \"never\") 99")
+  99)
+
+(hk-test
+  "constructor argument is lazy under wildcard pattern"
+  (hk-eval-expr-source
+    "case Just (error \"deeply\") of Just _ -> 7 ; Nothing -> 0")
+  7)
+
+(hk-test
+  "lazy: const drops its second argument"
+  (hk-prog-val
+    "const x y = x\nresult = const 5 (error \"boom\")"
+    "result")
+  5)
+
+(hk-test
+  "lazy: head ignores tail"
+  (hk-prog-val
+    "myHead (x:_) = x\nresult = myHead (1 : (error \"tail\") : [])"
+    "result")
+  1)
+
+(hk-test
+  "lazy: Just on undefined evaluates only on force"
+  (hk-prog-val
+    "wrapped = Just (error \"oh no\")\nresult = case wrapped of Just _ -> True ; Nothing -> False"
+    "result")
+  (list "True"))
+
+;; ── not / id built-ins ──
+(hk-test "not True" (hk-eval-expr-source "not True") (list "False"))
+(hk-test "not False" (hk-eval-expr-source "not False") (list "True"))
+(hk-test "id" (hk-eval-expr-source "id 42") 42)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/infer.sx

@@ -0,0 +1,181 @@
+;; infer.sx tests — Algorithm W: literals, vars, lambdas, application, let,
+;; if, operators, tuples, lists, let-polymorphism.
+
+(define hk-t (fn (src expected)
+  (hk-test (str "infer: " src) (hk-infer-type src) expected)))
+
+;; ─── Literals ────────────────────────────────────────────────────────────────
+(hk-t "1"          "Int")
+(hk-t "3.14"       "Float")
+(hk-t "\"hello\""  "String")
+(hk-t "'x'"        "Char")
+(hk-t "True"       "Bool")
+(hk-t "False"      "Bool")
+
+;; ─── Arithmetic and boolean operators ────────────────────────────────────────
+(hk-t "1 + 2"      "Int")
+(hk-t "3 * 4"      "Int")
+(hk-t "10 - 3"     "Int")
+(hk-t "True && False" "Bool")
+(hk-t "True || False" "Bool")
+(hk-t "not True"   "Bool")
+(hk-t "1 == 1"     "Bool")
+(hk-t "1 < 2"      "Bool")
+
+;; ─── Lambda ───────────────────────────────────────────────────────────────────
+;; \x -> x   (identity)  should get t1 -> t1
+(hk-test "infer: identity lambda" (hk-infer-type "\\x -> x") "t1 -> t1")
+
+;; \x -> x + 1 : Int -> Int
+(hk-test "infer: lambda add" (hk-infer-type "\\x -> x + 1") "Int -> Int")
+
+;; \x -> not x : Bool -> Bool
+(hk-test "infer: lambda not" (hk-infer-type "\\x -> not x") "Bool -> Bool")
+
+;; \x y -> x + y : Int -> Int -> Int
+(hk-test "infer: two-arg lambda" (hk-infer-type "\\x -> \\y -> x + y") "Int -> Int -> Int")
+
+;; ─── Application ─────────────────────────────────────────────────────────────
+(hk-t "not True"    "Bool")
+(hk-t "negate 1"    "Int")
+
+;; ─── If-then-else ─────────────────────────────────────────────────────────────
+(hk-t "if True then 1 else 2"     "Int")
+(hk-t "if 1 == 2 then True else False" "Bool")
+
+;; ─── Let bindings ─────────────────────────────────────────────────────────────
+;; let x = 1 in x + 2
+(hk-t "let x = 1 in x + 2" "Int")
+
+;; let f x = x + 1 in f 5
+(hk-t "let f x = x + 1 in f 5" "Int")
+
+;; let-polymorphism: let id x = x in id 1
+(hk-t "let id x = x in id 1" "Int")
+
+;; ─── Tuples ───────────────────────────────────────────────────────────────────
+(hk-t "(1, True)"       "(Int, Bool)")
+(hk-t "(1, 2, 3)"       "(Int, Int, Int)")
+
+;; ─── Lists ───────────────────────────────────────────────────────────────────
+(hk-t "[1, 2, 3]"    "[Int]")
+(hk-t "[True, False]" "[Bool]")
+
+;; ─── Polymorphic list functions ───────────────────────────────────────────────
+(hk-t "length [1, 2, 3]"   "Int")
+(hk-t "null []"             "Bool")
+(hk-t "head [1, 2, 3]"     "Int")
+
+;; ─── hk-expr->brief ──────────────────────────────────────────────────────────
+(hk-test "brief var"    (hk-expr->brief (list "var" "x"))           "x")
+(hk-test "brief con"    (hk-expr->brief (list "con" "Just"))        "Just")
+(hk-test "brief int"    (hk-expr->brief (list "int" 42))            "42")
+(hk-test "brief app"    (hk-expr->brief (list "app" (list "var" "f") (list "var" "x"))) "(f x)")
+(hk-test "brief op"     (hk-expr->brief (list "op" "+" (list "int" 1) (list "int" 2))) "(1 + 2)")
+(hk-test "brief lambda" (hk-expr->brief (list "lambda" (list) (list "var" "x"))) "(\\ ...)")
+(hk-test "brief loc"    (hk-expr->brief (list "loc" 3 7 (list "var" "x"))) "x")
+
+;; ─── Type error messages ─────────────────────────────────────────────────────
+;; Helper: catch the error and check it contains a substring.
+(define hk-str-has? (fn (s sub) (>= (index-of s sub) 0)))
+
+(define hk-te
+  (fn (label src sub)
+    (hk-test label
+      (guard (e (#t (hk-str-has? e sub)))
+        (begin (hk-infer-type src) false))
+      true)))
+
+;; Unbound variable error includes the variable name.
+(hk-te "error unbound name" "foo + 1"    "foo")
+(hk-te "error unbound unk"  "unknown"    "unknown")
+
+;; Unification error mentions the conflicting types.
+(hk-te "error unify int-bool-1" "1 + True"  "Int")
+(hk-te "error unify int-bool-2" "1 + True"  "Bool")
+
+;; ─── Loc node: passes through to inner (position decorates outer context) ────
+(define hk-loc-err-msg
+  (fn ()
+    (guard (e (#t e))
+      (begin
+        (hk-reset-fresh)
+        (hk-w (hk-type-env0) (list "loc" 5 10 (list "var" "mystery")))
+        "no-error"))))
+(hk-test "loc passes through to var error"
+  (hk-str-has? (hk-loc-err-msg) "mystery")
+  true)
+
+;; ─── hk-infer-decl ───────────────────────────────────────────────────────────
+;; Returns ("ok" name type) | ("err" msg)
+(define hk-env0-t (hk-type-env0))
+
+(define prog1 (hk-core "f x = x + 1"))
+(define decl1 (first (nth prog1 1)))
+(define res1 (hk-infer-decl hk-env0-t decl1))
+(hk-test "decl result tag"  (first res1)    "ok")
+(hk-test "decl result name" (nth res1 1)    "f")
+(hk-test "decl result type" (nth res1 2)    "Int -> Int")
+
+;; Error decl: result is ("err" "in 'g': ...")
+(define prog2 (hk-core "g x = x + True"))
+(define decl2 (first (nth prog2 1)))
+(define res2 (hk-infer-decl hk-env0-t decl2))
+(hk-test "decl error tag"    (first res2)                  "err")
+(hk-test "decl error has g"  (hk-str-has? (nth res2 1) "g")   true)
+(hk-test "decl error has msg" (hk-str-has? (nth res2 1) "unify") true)
+
+;; ─── hk-infer-prog ───────────────────────────────────────────────────────────
+;; Returns list of ("ok"/"err" ...) tagged results.
+(define prog3 (hk-core "double x = x + x\ntwice f x = f (f x)"))
+(define results3 (hk-infer-prog prog3 hk-env0-t))
+;; results3 = (("ok" "double" "Int -> Int") ("ok" "twice" "..."))
+(hk-test "infer-prog count"  (len results3)               2)
+(hk-test "infer-prog double" (nth (nth results3 0) 2)     "Int -> Int")
+(hk-test "infer-prog twice"  (nth (nth results3 1) 2)     "(t3 -> t3) -> t3 -> t3")
+
+(hk-t "let id x = x in id 1" "Int")
+
+(hk-t "let id x = x in id True" "Bool")
+
+(hk-t "let id x = x in (id 1, id True)" "(Int, Bool)")
+
+(hk-t "let const x y = x in (const 1 True, const True 1)" "(Int, Bool)")
+
+(hk-t "let f x = x in let g y = f y in (g 1, g True)" "(Int, Bool)")
+
+(hk-t "let twice f x = f (f x) in twice (\x -> x + 1) 5" "Int")
+
+(hk-t "not (not True)" "Bool")
+
+(hk-t "negate (negate 1)" "Int")
+
+(hk-t "\\x -> \\y -> x && y" "Bool -> Bool -> Bool")
+
+(hk-t "\\x -> x == 1" "Int -> Bool")
+
+(hk-t "let x = True in if x then 1 else 0" "Int")
+
+(hk-t "let f x = not x in f True" "Bool")
+
+(hk-t "let f x = (x, x + 1) in f 5" "(Int, Int)")
+
+(hk-t "let x = 1 in let y = 2 in x + y" "Int")
+
+(hk-t "let f x = x + 1 in f (f 5)" "Int")
+
+(hk-t "if 1 < 2 then True else False" "Bool")
+
+(hk-t "if True then 1 + 1 else 2 + 2" "Int")
+
+(hk-t "(1 + 2, True && False)" "(Int, Bool)")
+
+(hk-t "(1 == 1, 2 < 3)" "(Bool, Bool)")
+
+(hk-t "length [True, False]" "Int")
+
+(hk-t "null [1]" "Bool")
+
+(hk-t "[True]" "[Bool]")
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/infinite.sx

@@ -0,0 +1,137 @@
+;; Infinite structures + Prelude tests. The lazy `:` operator builds
+;; cons cells with thunked head/tail so recursive list-defining
+;; functions terminate when only a finite prefix is consumed.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define hk-as-list
+  (fn (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-eval-list
+  (fn (src) (hk-as-list (hk-eval-expr-source src))))
+
+;; ── Prelude basics ──
+(hk-test "head of literal" (hk-eval-expr-source "head [1, 2, 3]") 1)
+(hk-test
+  "tail of literal"
+  (hk-eval-list "tail [1, 2, 3]")
+  (list 2 3))
+(hk-test "length" (hk-eval-expr-source "length [10, 20, 30, 40]") 4)
+(hk-test "length empty" (hk-eval-expr-source "length []") 0)
+(hk-test
+  "map with section"
+  (hk-eval-list "map (+ 1) [1, 2, 3]")
+  (list 2 3 4))
+(hk-test
+  "filter"
+  (hk-eval-list "filter (\\x -> x > 2) [1, 2, 3, 4, 5]")
+  (list 3 4 5))
+(hk-test
+  "drop"
+  (hk-eval-list "drop 2 [10, 20, 30, 40]")
+  (list 30 40))
+(hk-test "fst" (hk-eval-expr-source "fst (7, 9)") 7)
+(hk-test "snd" (hk-eval-expr-source "snd (7, 9)") 9)
+(hk-test
+  "zipWith"
+  (hk-eval-list "zipWith plus [1, 2, 3] [10, 20, 30]")
+  (list 11 22 33))
+
+;; ── Infinite structures ──
+(hk-test
+  "take from repeat"
+  (hk-eval-list "take 5 (repeat 7)")
+  (list 7 7 7 7 7))
+(hk-test
+  "take 0 from repeat returns empty"
+  (hk-eval-list "take 0 (repeat 7)")
+  (list))
+(hk-test
+  "take from iterate"
+  (hk-eval-list "take 5 (iterate (\\x -> x + 1) 0)")
+  (list 0 1 2 3 4))
+(hk-test
+  "iterate with multiplication"
+  (hk-eval-list "take 4 (iterate (\\x -> x * 2) 1)")
+  (list 1 2 4 8))
+(hk-test
+  "head of repeat"
+  (hk-eval-expr-source "head (repeat 99)")
+  99)
+
+;; ── Fibonacci stream ──
+(hk-test
+  "first 10 Fibonacci numbers"
+  (hk-eval-list "take 10 fibs")
+  (list 0 1 1 2 3 5 8 13 21 34))
+(hk-test
+  "fib at position 8"
+  (hk-eval-expr-source "head (drop 8 fibs)")
+  21)
+
+;; ── Building infinite structures in user code ──
+(hk-test
+  "user-defined infinite ones"
+  (hk-prog-val
+    "ones = 1 : ones\nresult = take 6 ones"
+    "result")
+  (list ":" 1 (list ":" 1 (list ":" 1 (list ":" 1 (list ":" 1 (list ":" 1 (list "[]"))))))))
+
+(hk-test
+  "user-defined nats"
+  (hk-prog-val
+    "nats = naturalsFrom 1\nnaturalsFrom n = n : naturalsFrom (n + 1)\nresult = take 5 nats"
+    "result")
+  (list ":" 1 (list ":" 2 (list ":" 3 (list ":" 4 (list ":" 5 (list "[]")))))))
+
+;; ── Range syntax ──
+(hk-test
+  "finite range [1..5]"
+  (hk-eval-list "[1..5]")
+  (list 1 2 3 4 5))
+(hk-test
+  "empty range when from > to"
+  (hk-eval-list "[10..3]")
+  (list))
+(hk-test
+  "stepped range"
+  (hk-eval-list "[1, 3..10]")
+  (list 1 3 5 7 9))
+(hk-test
+  "open range — head"
+  (hk-eval-expr-source "head [1..]")
+  1)
+(hk-test
+  "open range — drop then head"
+  (hk-eval-expr-source "head (drop 99 [1..])")
+  100)
+(hk-test
+  "open range — take 5"
+  (hk-eval-list "take 5 [10..]")
+  (list 10 11 12 13 14))
+
+;; ── Composing Prelude functions ──
+(hk-test
+  "map then filter"
+  (hk-eval-list
+    "filter (\\x -> x > 5) (map (\\x -> x * 2) [1, 2, 3, 4])")
+  (list 6 8))
+
+(hk-test
+  "sum-via-foldless"
+  (hk-prog-val
+    "mySum [] = 0\nmySum (x:xs) = x + mySum xs\nresult = mySum (take 5 (iterate (\\x -> x + 1) 1))"
+    "result")
+  15)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/io-input.sx

@@ -0,0 +1,85 @@
+;; io-input.sx — tests for getLine, getContents, readFile, writeFile.
+
+(hk-test
+  "getLine reads single line"
+  (hk-run-io-with-input "main = getLine >>= putStrLn" (list "hello"))
+  (list "hello"))
+
+(hk-test
+  "getLine reads two lines"
+  (hk-run-io-with-input
+    "main = do { line1 <- getLine; line2 <- getLine; putStrLn line1; putStrLn line2 }"
+    (list "first" "second"))
+  (list "first" "second"))
+
+(hk-test
+  "getLine bind in layout do"
+  (hk-run-io-with-input
+    "main = do\n  line <- getLine\n  putStrLn line"
+    (list "world"))
+  (list "world"))
+
+(hk-test
+  "getLine echo with prefix"
+  (hk-run-io-with-input
+    "main = do\n  line <- getLine\n  putStrLn (\"Got: \" ++ line)"
+    (list "test"))
+  (list "Got: test"))
+
+(hk-test
+  "getContents reads all lines joined"
+  (hk-run-io-with-input
+    "main = getContents >>= putStr"
+    (list "line1" "line2" "line3"))
+  (list "line1\nline2\nline3"))
+
+(hk-test
+  "getContents empty stdin"
+  (hk-run-io-with-input "main = getContents >>= putStr" (list))
+  (list ""))
+
+(hk-test
+  "readFile reads pre-loaded content"
+  (begin
+    (set! hk-vfs (dict))
+    (dict-set! hk-vfs "hello.txt" "Hello, World!")
+    (hk-run-io "main = readFile \"hello.txt\" >>= putStrLn"))
+  (list "Hello, World!"))
+
+(hk-test
+  "writeFile creates file"
+  (begin
+    (set! hk-vfs (dict))
+    (hk-run-io "main = writeFile \"out.txt\" \"written content\"")
+    (get hk-vfs "out.txt"))
+  "written content")
+
+(hk-test
+  "writeFile then readFile roundtrip"
+  (begin
+    (set! hk-vfs (dict))
+    (hk-run-io
+      "main = do { writeFile \"f.txt\" \"round trip\"; readFile \"f.txt\" >>= putStrLn }"))
+  (list "round trip"))
+
+(hk-test
+  "readFile error on missing file"
+  (guard
+    (e (true (>= (index-of e "file not found") 0)))
+    (begin
+      (set! hk-vfs (dict))
+      (hk-run-io "main = readFile \"no.txt\" >>= putStrLn")
+      false))
+  true)
+
+(hk-test
+  "getLine then writeFile combined"
+  (begin
+    (set! hk-vfs (dict))
+    (hk-run-io-with-input
+      "main = do\n  line <- getLine\n  writeFile \"cap.txt\" line"
+      (list "captured"))
+    (get hk-vfs "cap.txt"))
+  "captured")
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/layout.sx

@@ -0,0 +1,245 @@
+;; Haskell layout-rule tests. hk-tokenizer + hk-layout produce a
+;; virtual-brace-annotated stream; these tests cover the algorithm
+;; from Haskell 98 §10.3 plus the pragmatic let/in single-line rule.
+
+;; Convenience — tokenize, run layout, strip eof, keep :type/:value.
+(define
+  hk-lay
+  (fn
+    (src)
+    (map
+      (fn (tok) {:value (get tok "value") :type (get tok "type")})
+      (filter
+        (fn (tok) (not (= (get tok "type") "eof")))
+        (hk-layout (hk-tokenize src))))))
+
+;; ── 1. Basics ──
+(hk-test
+  "empty input produces empty module { }"
+  (hk-lay "")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "}" :type "vrbrace"}))
+
+(hk-test
+  "single token → module open+close"
+  (hk-lay "foo")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "foo" :type "varid"}
+    {:value "}" :type "vrbrace"}))
+
+(hk-test
+  "two top-level decls get vsemi between"
+  (hk-lay "foo = 1\nbar = 2")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "foo" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 1 :type "integer"}
+    {:value ";" :type "vsemi"}
+    {:value "bar" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 2 :type "integer"}
+    {:value "}" :type "vrbrace"}))
+
+;; ── 2. Layout keywords — do / let / where / of ──
+(hk-test
+  "do block with two stmts"
+  (hk-lay "f = do\n  x\n  y")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "f" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value "do" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "x" :type "varid"}
+    {:value ";" :type "vsemi"}
+    {:value "y" :type "varid"}
+    {:value "}" :type "vrbrace"}
+    {:value "}" :type "vrbrace"}))
+
+(hk-test
+  "single-line let ... in"
+  (hk-lay "let x = 1 in x")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "let" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "x" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 1 :type "integer"}
+    {:value "}" :type "vrbrace"}
+    {:value "in" :type "reserved"}
+    {:value "x" :type "varid"}
+    {:value "}" :type "vrbrace"}))
+
+(hk-test
+  "where block with two bindings"
+  (hk-lay "f = g\n  where\n    g = 1\n    h = 2")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "f" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value "g" :type "varid"}
+    {:value "where" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "g" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 1 :type "integer"}
+    {:value ";" :type "vsemi"}
+    {:value "h" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 2 :type "integer"}
+    {:value "}" :type "vrbrace"}
+    {:value "}" :type "vrbrace"}))
+
+(hk-test
+  "case … of with arms"
+  (hk-lay "f x = case x of\n  Just y -> y\n  Nothing -> 0")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "f" :type "varid"}
+    {:value "x" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value "case" :type "reserved"}
+    {:value "x" :type "varid"}
+    {:value "of" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "Just" :type "conid"}
+    {:value "y" :type "varid"}
+    {:value "->" :type "reservedop"}
+    {:value "y" :type "varid"}
+    {:value ";" :type "vsemi"}
+    {:value "Nothing" :type "conid"}
+    {:value "->" :type "reservedop"}
+    {:value 0 :type "integer"}
+    {:value "}" :type "vrbrace"}
+    {:value "}" :type "vrbrace"}))
+
+;; ── 3. Explicit braces disable layout ──
+(hk-test
+  "explicit braces — no implicit vlbrace/vsemi/vrbrace inside"
+  (hk-lay "do { x ; y }")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "do" :type "reserved"}
+    {:value "{" :type "lbrace"}
+    {:value "x" :type "varid"}
+    {:value ";" :type "semi"}
+    {:value "y" :type "varid"}
+    {:value "}" :type "rbrace"}
+    {:value "}" :type "vrbrace"}))
+
+;; ── 4. Dedent closes nested blocks ──
+(hk-test
+  "dedent back to module level closes do block"
+  (hk-lay "f = do\n  x\n  y\ng = 2")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "f" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value "do" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "x" :type "varid"}
+    {:value ";" :type "vsemi"}
+    {:value "y" :type "varid"}
+    {:value "}" :type "vrbrace"}
+    {:value ";" :type "vsemi"}
+    {:value "g" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 2 :type "integer"}
+    {:value "}" :type "vrbrace"}))
+
+(hk-test
+  "dedent closes inner let, emits vsemi at outer do level"
+  (hk-lay "main = do\n  let x = 1\n  print x")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "main" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value "do" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "let" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "x" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 1 :type "integer"}
+    {:value "}" :type "vrbrace"}
+    {:value ";" :type "vsemi"}
+    {:value "print" :type "varid"}
+    {:value "x" :type "varid"}
+    {:value "}" :type "vrbrace"}
+    {:value "}" :type "vrbrace"}))
+
+;; ── 5. Module header skips outer implicit open ──
+(hk-test
+  "module M where — only where opens a block"
+  (hk-lay "module M where\n  f = 1")
+  (list
+    {:value "module" :type "reserved"}
+    {:value "M" :type "conid"}
+    {:value "where" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "f" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 1 :type "integer"}
+    {:value "}" :type "vrbrace"}))
+
+;; ── 6. Newlines are stripped ──
+(hk-test
+  "newline tokens do not appear in output"
+  (let
+    ((toks (hk-layout (hk-tokenize "foo\nbar"))))
+    (every?
+      (fn (t) (not (= (get t "type") "newline")))
+      toks))
+  true)
+
+;; ── 7. Continuation — deeper indent does NOT emit vsemi ──
+(hk-test
+  "line continuation (deeper indent) just merges"
+  (hk-lay "foo = 1 +\n   2")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "foo" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 1 :type "integer"}
+    {:value "+" :type "varsym"}
+    {:value 2 :type "integer"}
+    {:value "}" :type "vrbrace"}))
+
+;; ── 8. Stack closing at EOF ──
+(hk-test
+  "EOF inside nested do closes all implicit blocks"
+  (let
+    ((toks (hk-lay "main = do\n  do\n    x")))
+    (let
+      ((n (len toks)))
+      (list
+        (get (nth toks (- n 1)) "type")
+        (get (nth toks (- n 2)) "type")
+        (get (nth toks (- n 3)) "type"))))
+  (list "vrbrace" "vrbrace" "vrbrace"))
+
+;; ── 9. Qualified-newline: x at deeper col than stack top does nothing ──
+(hk-test
+  "mixed where + do"
+  (hk-lay "f = do\n    x\n  where\n    x = 1")
+  (list
+    {:value "{" :type "vlbrace"}
+    {:value "f" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value "do" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "x" :type "varid"}
+    {:value "}" :type "vrbrace"}
+    {:value "where" :type "reserved"}
+    {:value "{" :type "vlbrace"}
+    {:value "x" :type "varid"}
+    {:value "=" :type "reservedop"}
+    {:value 1 :type "integer"}
+    {:value "}" :type "vrbrace"}
+    {:value "}" :type "vrbrace"}))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/match.sx

@@ -0,0 +1,256 @@
+;; Pattern-matcher tests. The matcher takes (pat val env) and returns
+;; an extended env dict on success, or `nil` on failure. Constructor
+;; values are tagged lists (con-name first); tuples use the "Tuple"
+;; tag; lists use chained `:` cons with `[]` nil.
+
+;; ── Atomic patterns ──
+(hk-test
+  "wildcard always matches"
+  (hk-match (list :p-wild) 42 (dict))
+  (dict))
+
+(hk-test
+  "var binds value"
+  (hk-match (list :p-var "x") 42 (dict))
+  {:x 42})
+
+(hk-test
+  "var preserves prior env"
+  (hk-match (list :p-var "y") 7 {:x 1})
+  {:x 1 :y 7})
+
+(hk-test
+  "int literal matches equal"
+  (hk-match (list :p-int 5) 5 (dict))
+  (dict))
+
+(hk-test
+  "int literal fails on mismatch"
+  (hk-match (list :p-int 5) 6 (dict))
+  nil)
+
+(hk-test
+  "negative int literal matches"
+  (hk-match (list :p-int -3) -3 (dict))
+  (dict))
+
+(hk-test
+  "string literal matches"
+  (hk-match (list :p-string "hi") "hi" (dict))
+  (dict))
+
+(hk-test
+  "string literal fails"
+  (hk-match (list :p-string "hi") "bye" (dict))
+  nil)
+
+(hk-test
+  "char literal matches"
+  (hk-match (list :p-char "a") "a" (dict))
+  (dict))
+
+;; ── Constructor patterns ──
+(hk-test
+  "0-arity con matches"
+  (hk-match
+    (list :p-con "Nothing" (list))
+    (hk-mk-con "Nothing" (list))
+    (dict))
+  (dict))
+
+(hk-test
+  "1-arity con matches and binds"
+  (hk-match
+    (list :p-con "Just" (list (list :p-var "y")))
+    (hk-mk-con "Just" (list 9))
+    (dict))
+  {:y 9})
+
+(hk-test
+  "con name mismatch fails"
+  (hk-match
+    (list :p-con "Just" (list (list :p-var "y")))
+    (hk-mk-con "Nothing" (list))
+    (dict))
+  nil)
+
+(hk-test
+  "con arity mismatch fails"
+  (hk-match
+    (list :p-con "Pair" (list (list :p-var "a") (list :p-var "b")))
+    (hk-mk-con "Pair" (list 1))
+    (dict))
+  nil)
+
+(hk-test
+  "nested con: Just (Just x)"
+  (hk-match
+    (list
+      :p-con
+      "Just"
+      (list
+        (list
+          :p-con
+          "Just"
+          (list (list :p-var "x")))))
+    (hk-mk-con "Just" (list (hk-mk-con "Just" (list 42))))
+    (dict))
+  {:x 42})
+
+;; ── Tuple patterns ──
+(hk-test
+  "2-tuple matches and binds"
+  (hk-match
+    (list
+      :p-tuple
+      (list (list :p-var "a") (list :p-var "b")))
+    (hk-mk-tuple (list 10 20))
+    (dict))
+  {:a 10 :b 20})
+
+(hk-test
+  "tuple arity mismatch fails"
+  (hk-match
+    (list
+      :p-tuple
+      (list (list :p-var "a") (list :p-var "b")))
+    (hk-mk-tuple (list 10 20 30))
+    (dict))
+  nil)
+
+;; ── List patterns ──
+(hk-test
+  "[] pattern matches empty list"
+  (hk-match (list :p-list (list)) (hk-mk-nil) (dict))
+  (dict))
+
+(hk-test
+  "[] pattern fails on non-empty"
+  (hk-match (list :p-list (list)) (hk-mk-list (list 1)) (dict))
+  nil)
+
+(hk-test
+  "[a] pattern matches singleton"
+  (hk-match
+    (list :p-list (list (list :p-var "a")))
+    (hk-mk-list (list 7))
+    (dict))
+  {:a 7})
+
+(hk-test
+  "[a, b] pattern matches pair-list and binds"
+  (hk-match
+    (list
+      :p-list
+      (list (list :p-var "a") (list :p-var "b")))
+    (hk-mk-list (list 1 2))
+    (dict))
+  {:a 1 :b 2})
+
+(hk-test
+  "[a, b] fails on too-long list"
+  (hk-match
+    (list
+      :p-list
+      (list (list :p-var "a") (list :p-var "b")))
+    (hk-mk-list (list 1 2 3))
+    (dict))
+  nil)
+
+;; Cons-style infix pattern (which the parser produces as :p-con ":")
+(hk-test
+  "cons (h:t) on non-empty list"
+  (hk-match
+    (list
+      :p-con
+      ":"
+      (list (list :p-var "h") (list :p-var "t")))
+    (hk-mk-list (list 1 2 3))
+    (dict))
+  {:h 1 :t (list ":" 2 (list ":" 3 (list "[]")))})
+
+(hk-test
+  "cons fails on empty list"
+  (hk-match
+    (list
+      :p-con
+      ":"
+      (list (list :p-var "h") (list :p-var "t")))
+    (hk-mk-nil)
+    (dict))
+  nil)
+
+;; ── as patterns ──
+(hk-test
+  "as binds whole + sub-pattern"
+  (hk-match
+    (list
+      :p-as
+      "all"
+      (list :p-con "Just" (list (list :p-var "x"))))
+    (hk-mk-con "Just" (list 99))
+    (dict))
+  {:all (list "Just" 99) :x 99})
+
+(hk-test
+  "as on wildcard binds whole"
+  (hk-match
+    (list :p-as "v" (list :p-wild))
+    "anything"
+    (dict))
+  {:v "anything"})
+
+(hk-test
+  "as fails when sub-pattern fails"
+  (hk-match
+    (list
+      :p-as
+      "n"
+      (list :p-con "Just" (list (list :p-var "x"))))
+    (hk-mk-con "Nothing" (list))
+    (dict))
+  nil)
+
+;; ── lazy ~ pattern (eager equivalent for now) ──
+(hk-test
+  "lazy pattern eager-matches its inner"
+  (hk-match
+    (list :p-lazy (list :p-var "y"))
+    42
+    (dict))
+  {:y 42})
+
+;; ── Source-driven: parse a real Haskell pattern, match a value ──
+(hk-test
+  "parsed pattern: Just x against Just 5"
+  (hk-match
+    (hk-parse-pat-source "Just x")
+    (hk-mk-con "Just" (list 5))
+    (dict))
+  {:x 5})
+
+(hk-test
+  "parsed pattern: x : xs against [10, 20, 30]"
+  (hk-match
+    (hk-parse-pat-source "x : xs")
+    (hk-mk-list (list 10 20 30))
+    (dict))
+  {:x 10 :xs (list ":" 20 (list ":" 30 (list "[]")))})
+
+(hk-test
+  "parsed pattern: (a, b) against (1, 2)"
+  (hk-match
+    (hk-parse-pat-source "(a, b)")
+    (hk-mk-tuple (list 1 2))
+    (dict))
+  {:a 1 :b 2})
+
+(hk-test
+  "parsed pattern: n@(Just x) against Just 7"
+  (hk-match
+    (hk-parse-pat-source "n@(Just x)")
+    (hk-mk-con "Just" (list 7))
+    (dict))
+  {:n (list "Just" 7) :x 7})
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/parse.sx

@@ -3,60 +3,8 @@
 ;; Lightweight runner: each test checks actual vs expected with
 ;; structural (deep) equality and accumulates pass/fail counters.
 ;; Final value of this file is a summary dict with :pass :fail :fails.
-
-(define
-  hk-deep=?
-  (fn
-    (a b)
-    (cond
-      ((= a b) true)
-      ((and (dict? a) (dict? b))
-        (let
-          ((ak (keys a)) (bk (keys b)))
-          (if
-            (not (= (len ak) (len bk)))
-            false
-            (every?
-              (fn
-                (k)
-                (and (has-key? b k) (hk-deep=? (get a k) (get b k))))
-              ak))))
-      ((and (list? a) (list? b))
-        (if
-          (not (= (len a) (len b)))
-          false
-          (let
-            ((i 0) (ok true))
-            (define
-              hk-de-loop
-              (fn
-                ()
-                (when
-                  (and ok (< i (len a)))
-                  (do
-                    (when
-                      (not (hk-deep=? (nth a i) (nth b i)))
-                      (set! ok false))
-                    (set! i (+ i 1))
-                    (hk-de-loop)))))
-            (hk-de-loop)
-            ok)))
-      (:else false))))
-
-(define hk-test-pass 0)
-(define hk-test-fail 0)
-(define hk-test-fails (list))
-
-(define
-  hk-test
-  (fn
-    (name actual expected)
-    (if
-      (hk-deep=? actual expected)
-      (set! hk-test-pass (+ hk-test-pass 1))
-      (do
-        (set! hk-test-fail (+ hk-test-fail 1))
-        (append! hk-test-fails {:actual actual :expected expected :name name})))))
+;; The hk-test / hk-deep=? helpers live in lib/haskell/testlib.sx
+;; and are preloaded by lib/haskell/test.sh.
 
 ;; Convenience: tokenize and drop newline + eof tokens so tests focus
 ;; on meaningful content. Returns list of {:type :value} pairs.

lib/haskell/tests/parser-case-do.sx

@@ -0,0 +1,278 @@
+;; case-of and do-notation parser tests.
+;; Covers the minimal patterns needed to make these meaningful: var,
+;; wildcard, literal, constructor (with and without args), tuple, list.
+
+;; ── Patterns (in case arms) ──
+(hk-test
+  "wildcard pat"
+  (hk-parse "case x of _ -> 0")
+  (list
+    :case
+    (list :var "x")
+    (list (list :alt (list :p-wild) (list :int 0)))))
+
+(hk-test
+  "var pat"
+  (hk-parse "case x of y -> y")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list :alt (list :p-var "y") (list :var "y")))))
+
+(hk-test
+  "0-arity constructor pat"
+  (hk-parse "case x of\n  Nothing -> 0\n  Just y -> y")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list :alt (list :p-con "Nothing" (list)) (list :int 0))
+      (list
+        :alt
+        (list :p-con "Just" (list (list :p-var "y")))
+        (list :var "y")))))
+
+(hk-test
+  "int literal pat"
+  (hk-parse "case n of\n  0 -> 1\n  _ -> n")
+  (list
+    :case
+    (list :var "n")
+    (list
+      (list :alt (list :p-int 0) (list :int 1))
+      (list :alt (list :p-wild) (list :var "n")))))
+
+(hk-test
+  "string literal pat"
+  (hk-parse "case s of\n  \"hi\" -> 1\n  _ -> 0")
+  (list
+    :case
+    (list :var "s")
+    (list
+      (list :alt (list :p-string "hi") (list :int 1))
+      (list :alt (list :p-wild) (list :int 0)))))
+
+(hk-test
+  "tuple pat"
+  (hk-parse "case p of (a, b) -> a")
+  (list
+    :case
+    (list :var "p")
+    (list
+      (list
+        :alt
+        (list
+          :p-tuple
+          (list (list :p-var "a") (list :p-var "b")))
+        (list :var "a")))))
+
+(hk-test
+  "list pat"
+  (hk-parse "case xs of\n  [] -> 0\n  [a] -> a")
+  (list
+    :case
+    (list :var "xs")
+    (list
+      (list :alt (list :p-list (list)) (list :int 0))
+      (list
+        :alt
+        (list :p-list (list (list :p-var "a")))
+        (list :var "a")))))
+
+(hk-test
+  "nested constructor pat"
+  (hk-parse "case x of\n  Just (a, b) -> a\n  _ -> 0")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list
+          :p-con
+          "Just"
+          (list
+            (list
+              :p-tuple
+              (list (list :p-var "a") (list :p-var "b")))))
+        (list :var "a"))
+      (list :alt (list :p-wild) (list :int 0)))))
+
+(hk-test
+  "constructor with multiple var args"
+  (hk-parse "case t of Pair a b -> a")
+  (list
+    :case
+    (list :var "t")
+    (list
+      (list
+        :alt
+        (list
+          :p-con
+          "Pair"
+          (list (list :p-var "a") (list :p-var "b")))
+        (list :var "a")))))
+
+;; ── case-of shapes ──
+(hk-test
+  "case with explicit braces"
+  (hk-parse "case x of { Just y -> y ; Nothing -> 0 }")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list :p-con "Just" (list (list :p-var "y")))
+        (list :var "y"))
+      (list :alt (list :p-con "Nothing" (list)) (list :int 0)))))
+
+(hk-test
+  "case scrutinee is a full expression"
+  (hk-parse "case f x + 1 of\n  y -> y")
+  (list
+    :case
+    (list
+      :op
+      "+"
+      (list :app (list :var "f") (list :var "x"))
+      (list :int 1))
+    (list (list :alt (list :p-var "y") (list :var "y")))))
+
+(hk-test
+  "case arm body is full expression"
+  (hk-parse "case x of\n  Just y -> y + 1")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list :p-con "Just" (list (list :p-var "y")))
+        (list :op "+" (list :var "y") (list :int 1))))))
+
+;; ── do blocks ──
+(hk-test
+  "do with two expressions"
+  (hk-parse "do\n  putStrLn \"hi\"\n  return 0")
+  (list
+    :do
+    (list
+      (list
+        :do-expr
+        (list :app (list :var "putStrLn") (list :string "hi")))
+      (list
+        :do-expr
+        (list :app (list :var "return") (list :int 0))))))
+
+(hk-test
+  "do with bind"
+  (hk-parse "do\n  x <- getLine\n  putStrLn x")
+  (list
+    :do
+    (list
+      (list :do-bind (list :p-var "x") (list :var "getLine"))
+      (list
+        :do-expr
+        (list :app (list :var "putStrLn") (list :var "x"))))))
+
+(hk-test
+  "do with let"
+  (hk-parse "do\n  let y = 5\n  print y")
+  (list
+    :do
+    (list
+      (list
+        :do-let
+        (list (list :bind (list :p-var "y") (list :int 5))))
+      (list
+        :do-expr
+        (list :app (list :var "print") (list :var "y"))))))
+
+(hk-test
+  "do with multiple let bindings"
+  (hk-parse "do\n  let x = 1\n      y = 2\n  print (x + y)")
+  (list
+    :do
+    (list
+      (list
+        :do-let
+        (list
+          (list :bind (list :p-var "x") (list :int 1))
+          (list :bind (list :p-var "y") (list :int 2))))
+      (list
+        :do-expr
+        (list
+          :app
+          (list :var "print")
+          (list :op "+" (list :var "x") (list :var "y")))))))
+
+(hk-test
+  "do with bind using constructor pat"
+  (hk-parse "do\n  Just x <- getMaybe\n  return x")
+  (list
+    :do
+    (list
+      (list
+        :do-bind
+        (list :p-con "Just" (list (list :p-var "x")))
+        (list :var "getMaybe"))
+      (list
+        :do-expr
+        (list :app (list :var "return") (list :var "x"))))))
+
+(hk-test
+  "do with explicit braces"
+  (hk-parse "do { x <- a ; y <- b ; return (x + y) }")
+  (list
+    :do
+    (list
+      (list :do-bind (list :p-var "x") (list :var "a"))
+      (list :do-bind (list :p-var "y") (list :var "b"))
+      (list
+        :do-expr
+        (list
+          :app
+          (list :var "return")
+          (list :op "+" (list :var "x") (list :var "y")))))))
+
+;; ── Mixing case/do inside expressions ──
+(hk-test
+  "case inside let"
+  (hk-parse "let f = \\x -> case x of\n                 Just y -> y\n                 _ -> 0\nin f 5")
+  (list
+    :let
+    (list
+      (list
+        :bind
+        (list :p-var "f")
+        (list
+          :lambda
+          (list (list :p-var "x"))
+          (list
+            :case
+            (list :var "x")
+            (list
+              (list
+                :alt
+                (list :p-con "Just" (list (list :p-var "y")))
+                (list :var "y"))
+              (list :alt (list :p-wild) (list :int 0)))))))
+    (list :app (list :var "f") (list :int 5))))
+
+(hk-test
+  "lambda containing do"
+  (hk-parse "\\x -> do\n  y <- x\n  return y")
+  (list
+    :lambda
+    (list (list :p-var "x"))
+    (list
+      :do
+      (list
+        (list :do-bind (list :p-var "y") (list :var "x"))
+        (list
+          :do-expr
+          (list :app (list :var "return") (list :var "y")))))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/parser-decls.sx

@@ -0,0 +1,273 @@
+;; Top-level declarations: function clauses, type signatures, data,
+;; type, newtype, fixity. Driven by hk-parse-top which produces
+;; a (:program DECLS) node.
+
+(define
+  hk-prog
+  (fn
+    (&rest decls)
+    (list :program decls)))
+
+;; ── Function clauses & pattern bindings ──
+(hk-test
+  "simple fun-clause"
+  (hk-parse-top "f x = x + 1")
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list :op "+" (list :var "x") (list :int 1)))))
+
+(hk-test
+  "nullary decl"
+  (hk-parse-top "answer = 42")
+  (hk-prog
+    (list :fun-clause "answer" (list) (list :int 42))))
+
+(hk-test
+  "multi-clause fn (separate defs for each pattern)"
+  (hk-parse-top "fact 0 = 1\nfact n = n")
+  (hk-prog
+    (list :fun-clause "fact" (list (list :p-int 0)) (list :int 1))
+    (list
+      :fun-clause
+      "fact"
+      (list (list :p-var "n"))
+      (list :var "n"))))
+
+(hk-test
+  "constructor pattern in fn args"
+  (hk-parse-top "fromJust (Just x) = x")
+  (hk-prog
+    (list
+      :fun-clause
+      "fromJust"
+      (list (list :p-con "Just" (list (list :p-var "x"))))
+      (list :var "x"))))
+
+(hk-test
+  "pattern binding at top level"
+  (hk-parse-top "(a, b) = pair")
+  (hk-prog
+    (list
+      :pat-bind
+      (list
+        :p-tuple
+        (list (list :p-var "a") (list :p-var "b")))
+      (list :var "pair"))))
+
+;; ── Type signatures ──
+(hk-test
+  "single-name sig"
+  (hk-parse-top "f :: Int -> Int")
+  (hk-prog
+    (list
+      :type-sig
+      (list "f")
+      (list :t-fun (list :t-con "Int") (list :t-con "Int")))))
+
+(hk-test
+  "multi-name sig"
+  (hk-parse-top "f, g, h :: Int -> Bool")
+  (hk-prog
+    (list
+      :type-sig
+      (list "f" "g" "h")
+      (list :t-fun (list :t-con "Int") (list :t-con "Bool")))))
+
+(hk-test
+  "sig with type application"
+  (hk-parse-top "f :: Maybe a -> a")
+  (hk-prog
+    (list
+      :type-sig
+      (list "f")
+      (list
+        :t-fun
+        (list :t-app (list :t-con "Maybe") (list :t-var "a"))
+        (list :t-var "a")))))
+
+(hk-test
+  "sig with list type"
+  (hk-parse-top "len :: [a] -> Int")
+  (hk-prog
+    (list
+      :type-sig
+      (list "len")
+      (list
+        :t-fun
+        (list :t-list (list :t-var "a"))
+        (list :t-con "Int")))))
+
+(hk-test
+  "sig with tuple and right-assoc ->"
+  (hk-parse-top "pair :: a -> b -> (a, b)")
+  (hk-prog
+    (list
+      :type-sig
+      (list "pair")
+      (list
+        :t-fun
+        (list :t-var "a")
+        (list
+          :t-fun
+          (list :t-var "b")
+          (list
+            :t-tuple
+            (list (list :t-var "a") (list :t-var "b"))))))))
+
+(hk-test
+  "sig + implementation together"
+  (hk-parse-top "id :: a -> a\nid x = x")
+  (hk-prog
+    (list
+      :type-sig
+      (list "id")
+      (list :t-fun (list :t-var "a") (list :t-var "a")))
+    (list
+      :fun-clause
+      "id"
+      (list (list :p-var "x"))
+      (list :var "x"))))
+
+;; ── data declarations ──
+(hk-test
+  "data Maybe"
+  (hk-parse-top "data Maybe a = Nothing | Just a")
+  (hk-prog
+    (list
+      :data
+      "Maybe"
+      (list "a")
+      (list
+        (list :con-def "Nothing" (list))
+        (list :con-def "Just" (list (list :t-var "a")))))))
+
+(hk-test
+  "data Either"
+  (hk-parse-top "data Either a b = Left a | Right b")
+  (hk-prog
+    (list
+      :data
+      "Either"
+      (list "a" "b")
+      (list
+        (list :con-def "Left" (list (list :t-var "a")))
+        (list :con-def "Right" (list (list :t-var "b")))))))
+
+(hk-test
+  "data with no type parameters"
+  (hk-parse-top "data Bool = True | False")
+  (hk-prog
+    (list
+      :data
+      "Bool"
+      (list)
+      (list
+        (list :con-def "True" (list))
+        (list :con-def "False" (list))))))
+
+(hk-test
+  "recursive data type"
+  (hk-parse-top "data Tree a = Leaf | Node (Tree a) a (Tree a)")
+  (hk-prog
+    (list
+      :data
+      "Tree"
+      (list "a")
+      (list
+        (list :con-def "Leaf" (list))
+        (list
+          :con-def
+          "Node"
+          (list
+            (list :t-app (list :t-con "Tree") (list :t-var "a"))
+            (list :t-var "a")
+            (list :t-app (list :t-con "Tree") (list :t-var "a"))))))))
+
+;; ── type synonyms ──
+(hk-test
+  "simple type synonym"
+  (hk-parse-top "type Name = String")
+  (hk-prog
+    (list :type-syn "Name" (list) (list :t-con "String"))))
+
+(hk-test
+  "parameterised type synonym"
+  (hk-parse-top "type Pair a = (a, a)")
+  (hk-prog
+    (list
+      :type-syn
+      "Pair"
+      (list "a")
+      (list
+        :t-tuple
+        (list (list :t-var "a") (list :t-var "a"))))))
+
+;; ── newtype ──
+(hk-test
+  "newtype"
+  (hk-parse-top "newtype Age = Age Int")
+  (hk-prog (list :newtype "Age" (list) "Age" (list :t-con "Int"))))
+
+(hk-test
+  "parameterised newtype"
+  (hk-parse-top "newtype Wrap a = Wrap a")
+  (hk-prog
+    (list :newtype "Wrap" (list "a") "Wrap" (list :t-var "a"))))
+
+;; ── fixity declarations ──
+(hk-test
+  "infixl with precedence"
+  (hk-parse-top "infixl 5 +:, -:")
+  (hk-prog (list :fixity "l" 5 (list "+:" "-:"))))
+
+(hk-test
+  "infixr"
+  (hk-parse-top "infixr 9 .")
+  (hk-prog (list :fixity "r" 9 (list "."))))
+
+(hk-test
+  "infix (non-assoc) default prec"
+  (hk-parse-top "infix ==")
+  (hk-prog (list :fixity "n" 9 (list "=="))))
+
+(hk-test
+  "fixity with backtick operator name"
+  (hk-parse-top "infixl 7 `div`")
+  (hk-prog (list :fixity "l" 7 (list "div"))))
+
+;; ── Several decls combined ──
+(hk-test
+  "mixed: data + sig + fn + type"
+  (hk-parse-top "data Maybe a = Nothing | Just a\ntype Entry = Maybe Int\nf :: Entry -> Int\nf (Just x) = x\nf Nothing = 0")
+  (hk-prog
+    (list
+      :data
+      "Maybe"
+      (list "a")
+      (list
+        (list :con-def "Nothing" (list))
+        (list :con-def "Just" (list (list :t-var "a")))))
+    (list
+      :type-syn
+      "Entry"
+      (list)
+      (list :t-app (list :t-con "Maybe") (list :t-con "Int")))
+    (list
+      :type-sig
+      (list "f")
+      (list :t-fun (list :t-con "Entry") (list :t-con "Int")))
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-con "Just" (list (list :p-var "x"))))
+      (list :var "x"))
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-con "Nothing" (list)))
+      (list :int 0))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/parser-expr.sx

@@ -0,0 +1,258 @@
+;; Haskell expression parser tests.
+;; hk-parse tokenises, runs layout, then parses. Output is an AST
+;; whose head is a keyword tag (evaluates to its string name).
+
+;; ── 1. Literals ──
+(hk-test "integer" (hk-parse "42") (list :int 42))
+(hk-test "float" (hk-parse "3.14") (list :float 3.14))
+(hk-test "string" (hk-parse "\"hi\"") (list :string "hi"))
+(hk-test "char" (hk-parse "'a'") (list :char "a"))
+
+;; ── 2. Variables and constructors ──
+(hk-test "varid" (hk-parse "foo") (list :var "foo"))
+(hk-test "conid" (hk-parse "Nothing") (list :con "Nothing"))
+(hk-test "qvarid" (hk-parse "Data.Map.lookup") (list :var "Data.Map.lookup"))
+(hk-test "qconid" (hk-parse "Data.Map") (list :con "Data.Map"))
+
+;; ── 3. Parens / unit / tuple ──
+(hk-test "parens strip" (hk-parse "(42)") (list :int 42))
+(hk-test "unit" (hk-parse "()") (list :con "()"))
+(hk-test
+  "2-tuple"
+  (hk-parse "(1, 2)")
+  (list :tuple (list (list :int 1) (list :int 2))))
+(hk-test
+  "3-tuple"
+  (hk-parse "(x, y, z)")
+  (list
+    :tuple
+    (list (list :var "x") (list :var "y") (list :var "z"))))
+
+;; ── 4. Lists ──
+(hk-test "empty list" (hk-parse "[]") (list :list (list)))
+(hk-test
+  "singleton list"
+  (hk-parse "[1]")
+  (list :list (list (list :int 1))))
+(hk-test
+  "list of ints"
+  (hk-parse "[1, 2, 3]")
+  (list
+    :list
+    (list (list :int 1) (list :int 2) (list :int 3))))
+(hk-test
+  "range"
+  (hk-parse "[1..10]")
+  (list :range (list :int 1) (list :int 10)))
+(hk-test
+  "range with step"
+  (hk-parse "[1, 3..10]")
+  (list
+    :range-step
+    (list :int 1)
+    (list :int 3)
+    (list :int 10)))
+
+;; ── 5. Application ──
+(hk-test
+  "one-arg app"
+  (hk-parse "f x")
+  (list :app (list :var "f") (list :var "x")))
+(hk-test
+  "multi-arg app is left-assoc"
+  (hk-parse "f x y z")
+  (list
+    :app
+    (list
+      :app
+      (list :app (list :var "f") (list :var "x"))
+      (list :var "y"))
+    (list :var "z")))
+(hk-test
+  "app with con"
+  (hk-parse "Just 5")
+  (list :app (list :con "Just") (list :int 5)))
+
+;; ── 6. Infix operators ──
+(hk-test
+  "simple +"
+  (hk-parse "1 + 2")
+  (list :op "+" (list :int 1) (list :int 2)))
+(hk-test
+  "precedence: * binds tighter than +"
+  (hk-parse "1 + 2 * 3")
+  (list
+    :op
+    "+"
+    (list :int 1)
+    (list :op "*" (list :int 2) (list :int 3))))
+(hk-test
+  "- is left-assoc"
+  (hk-parse "10 - 3 - 2")
+  (list
+    :op
+    "-"
+    (list :op "-" (list :int 10) (list :int 3))
+    (list :int 2)))
+(hk-test
+  ": is right-assoc"
+  (hk-parse "a : b : c")
+  (list
+    :op
+    ":"
+    (list :var "a")
+    (list :op ":" (list :var "b") (list :var "c"))))
+(hk-test
+  "app binds tighter than op"
+  (hk-parse "f x + g y")
+  (list
+    :op
+    "+"
+    (list :app (list :var "f") (list :var "x"))
+    (list :app (list :var "g") (list :var "y"))))
+(hk-test
+  "$ is lowest precedence, right-assoc"
+  (hk-parse "f $ g x")
+  (list
+    :op
+    "$"
+    (list :var "f")
+    (list :app (list :var "g") (list :var "x"))))
+
+;; ── 7. Backticks (varid-as-operator) ──
+(hk-test
+  "backtick operator"
+  (hk-parse "x `mod` 3")
+  (list :op "mod" (list :var "x") (list :int 3)))
+
+;; ── 8. Unary negation ──
+(hk-test
+  "unary -"
+  (hk-parse "- 5")
+  (list :neg (list :int 5)))
+(hk-test
+  "unary - on application"
+  (hk-parse "- f x")
+  (list :neg (list :app (list :var "f") (list :var "x"))))
+(hk-test
+  "- n + m → (- n) + m"
+  (hk-parse "- 1 + 2")
+  (list
+    :op
+    "+"
+    (list :neg (list :int 1))
+    (list :int 2)))
+
+;; ── 9. Lambda ──
+(hk-test
+  "lambda single param"
+  (hk-parse "\\x -> x")
+  (list :lambda (list (list :p-var "x")) (list :var "x")))
+(hk-test
+  "lambda multi-param"
+  (hk-parse "\\x y -> x + y")
+  (list
+    :lambda
+    (list (list :p-var "x") (list :p-var "y"))
+    (list :op "+" (list :var "x") (list :var "y"))))
+(hk-test
+  "lambda body is full expression"
+  (hk-parse "\\f -> f 1 + f 2")
+  (list
+    :lambda
+    (list (list :p-var "f"))
+    (list
+      :op
+      "+"
+      (list :app (list :var "f") (list :int 1))
+      (list :app (list :var "f") (list :int 2)))))
+
+;; ── 10. if-then-else ──
+(hk-test
+  "if basic"
+  (hk-parse "if x then 1 else 2")
+  (list :if (list :var "x") (list :int 1) (list :int 2)))
+(hk-test
+  "if with infix cond"
+  (hk-parse "if x == 0 then y else z")
+  (list
+    :if
+    (list :op "==" (list :var "x") (list :int 0))
+    (list :var "y")
+    (list :var "z")))
+
+;; ── 11. let-in ──
+(hk-test
+  "let single binding"
+  (hk-parse "let x = 1 in x")
+  (list
+    :let
+    (list (list :bind (list :p-var "x") (list :int 1)))
+    (list :var "x")))
+(hk-test
+  "let two bindings (multi-line)"
+  (hk-parse "let x = 1\n    y = 2\nin x + y")
+  (list
+    :let
+    (list
+      (list :bind (list :p-var "x") (list :int 1))
+      (list :bind (list :p-var "y") (list :int 2)))
+    (list :op "+" (list :var "x") (list :var "y"))))
+(hk-test
+  "let with explicit braces"
+  (hk-parse "let { x = 1 ; y = 2 } in x + y")
+  (list
+    :let
+    (list
+      (list :bind (list :p-var "x") (list :int 1))
+      (list :bind (list :p-var "y") (list :int 2)))
+    (list :op "+" (list :var "x") (list :var "y"))))
+
+;; ── 12. Mixed / nesting ──
+(hk-test
+  "nested application"
+  (hk-parse "f (g x) y")
+  (list
+    :app
+    (list
+      :app
+      (list :var "f")
+      (list :app (list :var "g") (list :var "x")))
+    (list :var "y")))
+(hk-test
+  "lambda applied"
+  (hk-parse "(\\x -> x + 1) 5")
+  (list
+    :app
+    (list
+      :lambda
+      (list (list :p-var "x"))
+      (list :op "+" (list :var "x") (list :int 1)))
+    (list :int 5)))
+(hk-test
+  "lambda + if"
+  (hk-parse "\\n -> if n == 0 then 1 else n")
+  (list
+    :lambda
+    (list (list :p-var "n"))
+    (list
+      :if
+      (list :op "==" (list :var "n") (list :int 0))
+      (list :int 1)
+      (list :var "n"))))
+
+;; ── 13. Precedence corners ──
+(hk-test
+  ". is right-assoc (prec 9)"
+  (hk-parse "f . g . h")
+  (list
+    :op
+    "."
+    (list :var "f")
+    (list :op "." (list :var "g") (list :var "h"))))
+(hk-test
+  "== is non-associative (single use)"
+  (hk-parse "x == y")
+  (list :op "==" (list :var "x") (list :var "y")))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/parser-guards-where.sx

@@ -0,0 +1,261 @@
+;; Guards and where-clauses — on fun-clauses, case alts, and
+;; let-bindings (which now also accept funclause-style LHS like
+;; `let f x = e` or `let f x | g = e | g = e`).
+
+(define
+  hk-prog
+  (fn (&rest decls) (list :program decls)))
+
+;; ── Guarded fun-clauses ──
+(hk-test
+  "simple guards (two branches)"
+  (hk-parse-top "abs x | x < 0 = - x\n      | otherwise = x")
+  (hk-prog
+    (list
+      :fun-clause
+      "abs"
+      (list (list :p-var "x"))
+      (list
+        :guarded
+        (list
+          (list
+            :guard
+            (list :op "<" (list :var "x") (list :int 0))
+            (list :neg (list :var "x")))
+          (list :guard (list :var "otherwise") (list :var "x")))))))
+
+(hk-test
+  "three-way guard"
+  (hk-parse-top "sign n | n > 0 = 1\n       | n < 0 = -1\n       | otherwise = 0")
+  (hk-prog
+    (list
+      :fun-clause
+      "sign"
+      (list (list :p-var "n"))
+      (list
+        :guarded
+        (list
+          (list
+            :guard
+            (list :op ">" (list :var "n") (list :int 0))
+            (list :int 1))
+          (list
+            :guard
+            (list :op "<" (list :var "n") (list :int 0))
+            (list :neg (list :int 1)))
+          (list
+            :guard
+            (list :var "otherwise")
+            (list :int 0)))))))
+
+(hk-test
+  "mixed: one eq clause plus one guarded clause"
+  (hk-parse-top "sign 0 = 0\nsign n | n > 0 = 1\n       | otherwise = -1")
+  (hk-prog
+    (list
+      :fun-clause
+      "sign"
+      (list (list :p-int 0))
+      (list :int 0))
+    (list
+      :fun-clause
+      "sign"
+      (list (list :p-var "n"))
+      (list
+        :guarded
+        (list
+          (list
+            :guard
+            (list :op ">" (list :var "n") (list :int 0))
+            (list :int 1))
+          (list
+            :guard
+            (list :var "otherwise")
+            (list :neg (list :int 1))))))))
+
+;; ── where on fun-clauses ──
+(hk-test
+  "where with one binding"
+  (hk-parse-top "f x = y + y\n  where y = x + 1")
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list
+        :where
+        (list :op "+" (list :var "y") (list :var "y"))
+        (list
+          (list
+            :fun-clause
+            "y"
+            (list)
+            (list :op "+" (list :var "x") (list :int 1))))))))
+
+(hk-test
+  "where with multiple bindings"
+  (hk-parse-top "f x = y * z\n  where y = x + 1\n        z = x - 1")
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list
+        :where
+        (list :op "*" (list :var "y") (list :var "z"))
+        (list
+          (list
+            :fun-clause
+            "y"
+            (list)
+            (list :op "+" (list :var "x") (list :int 1)))
+          (list
+            :fun-clause
+            "z"
+            (list)
+            (list :op "-" (list :var "x") (list :int 1))))))))
+
+(hk-test
+  "guards + where"
+  (hk-parse-top "f x | x > 0 = y\n    | otherwise = 0\n  where y = 99")
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list
+        :where
+        (list
+          :guarded
+          (list
+            (list
+              :guard
+              (list :op ">" (list :var "x") (list :int 0))
+              (list :var "y"))
+            (list
+              :guard
+              (list :var "otherwise")
+              (list :int 0))))
+        (list
+          (list :fun-clause "y" (list) (list :int 99)))))))
+
+;; ── Guards in case alts ──
+(hk-test
+  "case alt with guards"
+  (hk-parse "case x of\n  Just y | y > 0 -> y\n         | otherwise -> 0\n  Nothing -> 0")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list :p-con "Just" (list (list :p-var "y")))
+        (list
+          :guarded
+          (list
+            (list
+              :guard
+              (list :op ">" (list :var "y") (list :int 0))
+              (list :var "y"))
+            (list
+              :guard
+              (list :var "otherwise")
+              (list :int 0)))))
+      (list :alt (list :p-con "Nothing" (list)) (list :int 0)))))
+
+(hk-test
+  "case alt with where"
+  (hk-parse "case x of\n  Just y -> y + z where z = 5\n  Nothing -> 0")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list :p-con "Just" (list (list :p-var "y")))
+        (list
+          :where
+          (list :op "+" (list :var "y") (list :var "z"))
+          (list
+            (list :fun-clause "z" (list) (list :int 5)))))
+      (list :alt (list :p-con "Nothing" (list)) (list :int 0)))))
+
+;; ── let-bindings: funclause form, guards, where ──
+(hk-test
+  "let with funclause shorthand"
+  (hk-parse "let f x = x + 1 in f 5")
+  (list
+    :let
+    (list
+      (list
+        :fun-clause
+        "f"
+        (list (list :p-var "x"))
+        (list :op "+" (list :var "x") (list :int 1))))
+    (list :app (list :var "f") (list :int 5))))
+
+(hk-test
+  "let with guards"
+  (hk-parse "let f x | x > 0 = x\n        | otherwise = 0\nin f 3")
+  (list
+    :let
+    (list
+      (list
+        :fun-clause
+        "f"
+        (list (list :p-var "x"))
+        (list
+          :guarded
+          (list
+            (list
+              :guard
+              (list :op ">" (list :var "x") (list :int 0))
+              (list :var "x"))
+            (list
+              :guard
+              (list :var "otherwise")
+              (list :int 0))))))
+    (list :app (list :var "f") (list :int 3))))
+
+(hk-test
+  "let funclause + where"
+  (hk-parse "let f x = y where y = x + 1\nin f 7")
+  (list
+    :let
+    (list
+      (list
+        :fun-clause
+        "f"
+        (list (list :p-var "x"))
+        (list
+          :where
+          (list :var "y")
+          (list
+            (list
+              :fun-clause
+              "y"
+              (list)
+              (list :op "+" (list :var "x") (list :int 1)))))))
+    (list :app (list :var "f") (list :int 7))))
+
+;; ── Nested: where inside where (via recursive hk-parse-decl) ──
+(hk-test
+  "where block can contain a type signature"
+  (hk-parse-top "f x = y\n  where y :: Int\n        y = x")
+  (hk-prog
+    (list
+      :fun-clause
+      "f"
+      (list (list :p-var "x"))
+      (list
+        :where
+        (list :var "y")
+        (list
+          (list :type-sig (list "y") (list :t-con "Int"))
+          (list
+            :fun-clause
+            "y"
+            (list)
+            (list :var "x")))))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/parser-module.sx

@@ -0,0 +1,202 @@
+;; Module header + imports. The parser switches from (:program DECLS)
+;; to (:module NAME EXPORTS IMPORTS DECLS) as soon as a module header
+;; or any `import` decl appears.
+
+;; ── Module header ──
+(hk-test
+  "simple module, no exports"
+  (hk-parse-top "module M where\n  f = 1")
+  (list
+    :module
+    "M"
+    nil
+    (list)
+    (list (list :fun-clause "f" (list) (list :int 1)))))
+
+(hk-test
+  "module with dotted name"
+  (hk-parse-top "module Data.Map where\nf = 1")
+  (list
+    :module
+    "Data.Map"
+    nil
+    (list)
+    (list (list :fun-clause "f" (list) (list :int 1)))))
+
+(hk-test
+  "module with empty export list"
+  (hk-parse-top "module M () where\nf = 1")
+  (list
+    :module
+    "M"
+    (list)
+    (list)
+    (list (list :fun-clause "f" (list) (list :int 1)))))
+
+(hk-test
+  "module with exports (var, tycon-all, tycon-with)"
+  (hk-parse-top "module M (f, g, Maybe(..), List(Cons, Nil)) where\nf = 1\ng = 2")
+  (list
+    :module
+    "M"
+    (list
+      (list :ent-var "f")
+      (list :ent-var "g")
+      (list :ent-all "Maybe")
+      (list :ent-with "List" (list "Cons" "Nil")))
+    (list)
+    (list
+      (list :fun-clause "f" (list) (list :int 1))
+      (list :fun-clause "g" (list) (list :int 2)))))
+
+(hk-test
+  "module export list including another module"
+  (hk-parse-top "module M (module Foo, f) where\nf = 1")
+  (list
+    :module
+    "M"
+    (list (list :ent-module "Foo") (list :ent-var "f"))
+    (list)
+    (list (list :fun-clause "f" (list) (list :int 1)))))
+
+(hk-test
+  "module export with operator"
+  (hk-parse-top "module M ((+:), f) where\nf = 1")
+  (list
+    :module
+    "M"
+    (list (list :ent-var "+:") (list :ent-var "f"))
+    (list)
+    (list (list :fun-clause "f" (list) (list :int 1)))))
+
+(hk-test
+  "empty module body"
+  (hk-parse-top "module M where")
+  (list :module "M" nil (list) (list)))
+
+;; ── Imports ──
+(hk-test
+  "plain import"
+  (hk-parse-top "import Foo")
+  (list
+    :module
+    nil
+    nil
+    (list (list :import false "Foo" nil nil))
+    (list)))
+
+(hk-test
+  "qualified import"
+  (hk-parse-top "import qualified Data.Map")
+  (list
+    :module
+    nil
+    nil
+    (list (list :import true "Data.Map" nil nil))
+    (list)))
+
+(hk-test
+  "import with alias"
+  (hk-parse-top "import Data.Map as M")
+  (list
+    :module
+    nil
+    nil
+    (list (list :import false "Data.Map" "M" nil))
+    (list)))
+
+(hk-test
+  "import with explicit list"
+  (hk-parse-top "import Foo (bar, Baz(..), Quux(X, Y))")
+  (list
+    :module
+    nil
+    nil
+    (list
+      (list
+        :import
+        false
+        "Foo"
+        nil
+        (list
+          :spec-items
+          (list
+            (list :ent-var "bar")
+            (list :ent-all "Baz")
+            (list :ent-with "Quux" (list "X" "Y"))))))
+    (list)))
+
+(hk-test
+  "import hiding"
+  (hk-parse-top "import Foo hiding (x, y)")
+  (list
+    :module
+    nil
+    nil
+    (list
+      (list
+        :import
+        false
+        "Foo"
+        nil
+        (list
+          :spec-hiding
+          (list (list :ent-var "x") (list :ent-var "y")))))
+    (list)))
+
+(hk-test
+  "qualified + alias + hiding"
+  (hk-parse-top "import qualified Data.List as L hiding (sort)")
+  (list
+    :module
+    nil
+    nil
+    (list
+      (list
+        :import
+        true
+        "Data.List"
+        "L"
+        (list :spec-hiding (list (list :ent-var "sort")))))
+    (list)))
+
+;; ── Combinations ──
+(hk-test
+  "module with multiple imports and a decl"
+  (hk-parse-top "module M where\nimport Foo\nimport qualified Bar as B\nf = 1")
+  (list
+    :module
+    "M"
+    nil
+    (list
+      (list :import false "Foo" nil nil)
+      (list :import true "Bar" "B" nil))
+    (list (list :fun-clause "f" (list) (list :int 1)))))
+
+(hk-test
+  "headerless file with imports"
+  (hk-parse-top "import Foo\nimport Bar (baz)\nf = 1")
+  (list
+    :module
+    nil
+    nil
+    (list
+      (list :import false "Foo" nil nil)
+      (list
+        :import
+        false
+        "Bar"
+        nil
+        (list :spec-items (list (list :ent-var "baz")))))
+    (list (list :fun-clause "f" (list) (list :int 1)))))
+
+(hk-test
+  "plain program (no header, no imports) still uses :program"
+  (hk-parse-top "f = 1\ng = 2")
+  (list
+    :program
+    (list
+      (list :fun-clause "f" (list) (list :int 1))
+      (list :fun-clause "g" (list) (list :int 2)))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/parser-patterns.sx

@@ -0,0 +1,234 @@
+;; Full-pattern parser tests: as-patterns, lazy ~, negative literals,
+;; infix constructor patterns (`:`, any consym), lambda pattern args,
+;; and let pattern-bindings.
+
+;; ── as-patterns ──
+(hk-test
+  "as pattern, wraps constructor"
+  (hk-parse "case x of n@(Just y) -> n")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list
+          :p-as
+          "n"
+          (list :p-con "Just" (list (list :p-var "y"))))
+        (list :var "n")))))
+
+(hk-test
+  "as pattern, wraps wildcard"
+  (hk-parse "case x of all@_ -> all")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list
+        :alt
+        (list :p-as "all" (list :p-wild))
+        (list :var "all")))))
+
+(hk-test
+  "as in lambda"
+  (hk-parse "\\xs@(a : rest) -> xs")
+  (list
+    :lambda
+    (list
+      (list
+        :p-as
+        "xs"
+        (list
+          :p-con
+          ":"
+          (list (list :p-var "a") (list :p-var "rest")))))
+    (list :var "xs")))
+
+;; ── lazy patterns ──
+(hk-test
+  "lazy var"
+  (hk-parse "case x of ~y -> y")
+  (list
+    :case
+    (list :var "x")
+    (list
+      (list :alt (list :p-lazy (list :p-var "y")) (list :var "y")))))
+
+(hk-test
+  "lazy constructor"
+  (hk-parse "\\(~(Just x)) -> x")
+  (list
+    :lambda
+    (list
+      (list
+        :p-lazy
+        (list :p-con "Just" (list (list :p-var "x")))))
+    (list :var "x")))
+
+;; ── negative literal patterns ──
+(hk-test
+  "negative int pattern"
+  (hk-parse "case n of\n  -1 -> 0\n  _ -> n")
+  (list
+    :case
+    (list :var "n")
+    (list
+      (list :alt (list :p-int -1) (list :int 0))
+      (list :alt (list :p-wild) (list :var "n")))))
+
+(hk-test
+  "negative float pattern"
+  (hk-parse "case x of -0.5 -> 1")
+  (list
+    :case
+    (list :var "x")
+    (list (list :alt (list :p-float -0.5) (list :int 1)))))
+
+;; ── infix constructor patterns (`:` and any consym) ──
+(hk-test
+  "cons pattern"
+  (hk-parse "case xs of x : rest -> x")
+  (list
+    :case
+    (list :var "xs")
+    (list
+      (list
+        :alt
+        (list
+          :p-con
+          ":"
+          (list (list :p-var "x") (list :p-var "rest")))
+        (list :var "x")))))
+
+(hk-test
+  "cons is right-associative in pats"
+  (hk-parse "case xs of a : b : rest -> rest")
+  (list
+    :case
+    (list :var "xs")
+    (list
+      (list
+        :alt
+        (list
+          :p-con
+          ":"
+          (list
+            (list :p-var "a")
+            (list
+              :p-con
+              ":"
+              (list (list :p-var "b") (list :p-var "rest")))))
+        (list :var "rest")))))
+
+(hk-test
+  "consym pattern"
+  (hk-parse "case p of a :+: b -> a")
+  (list
+    :case
+    (list :var "p")
+    (list
+      (list
+        :alt
+        (list
+          :p-con
+          ":+:"
+          (list (list :p-var "a") (list :p-var "b")))
+        (list :var "a")))))
+
+;; ── lambda with pattern args ──
+(hk-test
+  "lambda with constructor pattern"
+  (hk-parse "\\(Just x) -> x")
+  (list
+    :lambda
+    (list (list :p-con "Just" (list (list :p-var "x"))))
+    (list :var "x")))
+
+(hk-test
+  "lambda with tuple pattern"
+  (hk-parse "\\(a, b) -> a + b")
+  (list
+    :lambda
+    (list
+      (list
+        :p-tuple
+        (list (list :p-var "a") (list :p-var "b"))))
+    (list :op "+" (list :var "a") (list :var "b"))))
+
+(hk-test
+  "lambda with wildcard"
+  (hk-parse "\\_ -> 42")
+  (list :lambda (list (list :p-wild)) (list :int 42)))
+
+(hk-test
+  "lambda with mixed apats"
+  (hk-parse "\\x _ (Just y) -> y")
+  (list
+    :lambda
+    (list
+      (list :p-var "x")
+      (list :p-wild)
+      (list :p-con "Just" (list (list :p-var "y"))))
+    (list :var "y")))
+
+;; ── let pattern-bindings ──
+(hk-test
+  "let tuple pattern-binding"
+  (hk-parse "let (x, y) = pair in x + y")
+  (list
+    :let
+    (list
+      (list
+        :bind
+        (list
+          :p-tuple
+          (list (list :p-var "x") (list :p-var "y")))
+        (list :var "pair")))
+    (list :op "+" (list :var "x") (list :var "y"))))
+
+(hk-test
+  "let constructor pattern-binding"
+  (hk-parse "let Just x = m in x")
+  (list
+    :let
+    (list
+      (list
+        :bind
+        (list :p-con "Just" (list (list :p-var "x")))
+        (list :var "m")))
+    (list :var "x")))
+
+(hk-test
+  "let cons pattern-binding"
+  (hk-parse "let (x : rest) = xs in x")
+  (list
+    :let
+    (list
+      (list
+        :bind
+        (list
+          :p-con
+          ":"
+          (list (list :p-var "x") (list :p-var "rest")))
+        (list :var "xs")))
+    (list :var "x")))
+
+;; ── do with constructor-pattern binds ──
+(hk-test
+  "do bind to tuple pattern"
+  (hk-parse "do\n  (a, b) <- pairs\n  return a")
+  (list
+    :do
+    (list
+      (list
+        :do-bind
+        (list
+          :p-tuple
+          (list (list :p-var "a") (list :p-var "b")))
+        (list :var "pairs"))
+      (list
+        :do-expr
+        (list :app (list :var "return") (list :var "a"))))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/parser-sect-comp.sx

@@ -0,0 +1,191 @@
+;; Operator sections and list comprehensions.
+
+;; ── Operator references (unchanged expr shape) ──
+(hk-test
+  "op as value (+)"
+  (hk-parse "(+)")
+  (list :var "+"))
+
+(hk-test
+  "op as value (-)"
+  (hk-parse "(-)")
+  (list :var "-"))
+
+(hk-test
+  "op as value (:)"
+  (hk-parse "(:)")
+  (list :var ":"))
+
+(hk-test
+  "backtick op as value"
+  (hk-parse "(`div`)")
+  (list :var "div"))
+
+;; ── Right sections (op expr) ──
+(hk-test
+  "right section (+ 5)"
+  (hk-parse "(+ 5)")
+  (list :sect-right "+" (list :int 5)))
+
+(hk-test
+  "right section (* x)"
+  (hk-parse "(* x)")
+  (list :sect-right "*" (list :var "x")))
+
+(hk-test
+  "right section with backtick op"
+  (hk-parse "(`div` 2)")
+  (list :sect-right "div" (list :int 2)))
+
+;; `-` is unary in expr position — (- 5) is negation, not a right section
+(hk-test
+  "(- 5) is negation, not a section"
+  (hk-parse "(- 5)")
+  (list :neg (list :int 5)))
+
+;; ── Left sections (expr op) ──
+(hk-test
+  "left section (5 +)"
+  (hk-parse "(5 +)")
+  (list :sect-left "+" (list :int 5)))
+
+(hk-test
+  "left section with backtick"
+  (hk-parse "(x `mod`)")
+  (list :sect-left "mod" (list :var "x")))
+
+(hk-test
+  "left section with cons (x :)"
+  (hk-parse "(x :)")
+  (list :sect-left ":" (list :var "x")))
+
+;; ── Mixed / nesting ──
+(hk-test
+  "map (+ 1) xs"
+  (hk-parse "map (+ 1) xs")
+  (list
+    :app
+    (list
+      :app
+      (list :var "map")
+      (list :sect-right "+" (list :int 1)))
+    (list :var "xs")))
+
+(hk-test
+  "filter (< 0) xs"
+  (hk-parse "filter (< 0) xs")
+  (list
+    :app
+    (list
+      :app
+      (list :var "filter")
+      (list :sect-right "<" (list :int 0)))
+    (list :var "xs")))
+
+;; ── Plain parens and tuples still work ──
+(hk-test
+  "plain parens unwrap"
+  (hk-parse "(1 + 2)")
+  (list :op "+" (list :int 1) (list :int 2)))
+
+(hk-test
+  "tuple still parses"
+  (hk-parse "(a, b, c)")
+  (list
+    :tuple
+    (list (list :var "a") (list :var "b") (list :var "c"))))
+
+;; ── List comprehensions ──
+(hk-test
+  "simple list comprehension"
+  (hk-parse "[x | x <- xs]")
+  (list
+    :list-comp
+    (list :var "x")
+    (list
+      (list :q-gen (list :p-var "x") (list :var "xs")))))
+
+(hk-test
+  "comprehension with filter"
+  (hk-parse "[x * 2 | x <- xs, x > 0]")
+  (list
+    :list-comp
+    (list :op "*" (list :var "x") (list :int 2))
+    (list
+      (list :q-gen (list :p-var "x") (list :var "xs"))
+      (list
+        :q-guard
+        (list :op ">" (list :var "x") (list :int 0))))))
+
+(hk-test
+  "comprehension with let"
+  (hk-parse "[y | x <- xs, let y = x + 1]")
+  (list
+    :list-comp
+    (list :var "y")
+    (list
+      (list :q-gen (list :p-var "x") (list :var "xs"))
+      (list
+        :q-let
+        (list
+          (list
+            :bind
+            (list :p-var "y")
+            (list :op "+" (list :var "x") (list :int 1))))))))
+
+(hk-test
+  "nested generators"
+  (hk-parse "[(x, y) | x <- xs, y <- ys]")
+  (list
+    :list-comp
+    (list :tuple (list (list :var "x") (list :var "y")))
+    (list
+      (list :q-gen (list :p-var "x") (list :var "xs"))
+      (list :q-gen (list :p-var "y") (list :var "ys")))))
+
+(hk-test
+  "comprehension with constructor pattern"
+  (hk-parse "[v | Just v <- xs]")
+  (list
+    :list-comp
+    (list :var "v")
+    (list
+      (list
+        :q-gen
+        (list :p-con "Just" (list (list :p-var "v")))
+        (list :var "xs")))))
+
+(hk-test
+  "comprehension with tuple pattern"
+  (hk-parse "[x + y | (x, y) <- pairs]")
+  (list
+    :list-comp
+    (list :op "+" (list :var "x") (list :var "y"))
+    (list
+      (list
+        :q-gen
+        (list
+          :p-tuple
+          (list (list :p-var "x") (list :p-var "y")))
+        (list :var "pairs")))))
+
+(hk-test
+  "combination: generator, let, guard"
+  (hk-parse "[z | x <- xs, let z = x * 2, z > 10]")
+  (list
+    :list-comp
+    (list :var "z")
+    (list
+      (list :q-gen (list :p-var "x") (list :var "xs"))
+      (list
+        :q-let
+        (list
+          (list
+            :bind
+            (list :p-var "z")
+            (list :op "*" (list :var "x") (list :int 2)))))
+      (list
+        :q-guard
+        (list :op ">" (list :var "z") (list :int 10))))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/prelude-extra.sx

@@ -0,0 +1,234 @@
+;; prelude-extra.sx — tests for Phase 6 prelude additions:
+;; ord/isAlpha/isDigit/isSpace/isUpper/isLower/isAlphaNum/digitToInt
+;; words/lines/unwords/unlines/sort/nub/splitAt/span/break
+;; partition/intercalate/intersperse/isPrefixOf/isSuffixOf/isInfixOf
+
+;; ── ord ──────────────────────────────────────────────────────
+(hk-test "ord 'A'" (hk-eval-expr-source "ord 'A'") 65)
+(hk-test "ord 'a'" (hk-eval-expr-source "ord 'a'") 97)
+(hk-test "ord '0'" (hk-eval-expr-source "ord '0'") 48)
+
+;; ── isAlpha / isDigit / isSpace / isUpper / isLower ──────────
+(hk-test
+  "isAlpha 'a' True"
+  (hk-eval-expr-source "isAlpha 'a'")
+  (list "True"))
+(hk-test
+  "isAlpha 'Z' True"
+  (hk-eval-expr-source "isAlpha 'Z'")
+  (list "True"))
+(hk-test
+  "isAlpha '3' False"
+  (hk-eval-expr-source "isAlpha '3'")
+  (list "False"))
+(hk-test
+  "isDigit '5' True"
+  (hk-eval-expr-source "isDigit '5'")
+  (list "True"))
+(hk-test
+  "isDigit 'a' False"
+  (hk-eval-expr-source "isDigit 'a'")
+  (list "False"))
+(hk-test
+  "isSpace ' ' True"
+  (hk-eval-expr-source "isSpace ' '")
+  (list "True"))
+(hk-test
+  "isSpace 'x' False"
+  (hk-eval-expr-source "isSpace 'x'")
+  (list "False"))
+(hk-test
+  "isUpper 'A' True"
+  (hk-eval-expr-source "isUpper 'A'")
+  (list "True"))
+(hk-test
+  "isUpper 'a' False"
+  (hk-eval-expr-source "isUpper 'a'")
+  (list "False"))
+(hk-test
+  "isLower 'z' True"
+  (hk-eval-expr-source "isLower 'z'")
+  (list "True"))
+(hk-test
+  "isLower 'Z' False"
+  (hk-eval-expr-source "isLower 'Z'")
+  (list "False"))
+(hk-test
+  "isAlphaNum '3' True"
+  (hk-eval-expr-source "isAlphaNum '3'")
+  (list "True"))
+(hk-test
+  "isAlphaNum 'b' True"
+  (hk-eval-expr-source "isAlphaNum 'b'")
+  (list "True"))
+(hk-test
+  "isAlphaNum '!' False"
+  (hk-eval-expr-source "isAlphaNum '!'")
+  (list "False"))
+
+;; ── digitToInt ───────────────────────────────────────────────
+(hk-test "digitToInt '0'" (hk-eval-expr-source "digitToInt '0'") 0)
+(hk-test "digitToInt '7'" (hk-eval-expr-source "digitToInt '7'") 7)
+(hk-test "digitToInt '9'" (hk-eval-expr-source "digitToInt '9'") 9)
+
+;; ── words ────────────────────────────────────────────────────
+(hk-test
+  "words single"
+  (hk-deep-force (hk-eval-expr-source "words \"hello\""))
+  (list ":" "hello" (list "[]")))
+
+(hk-test
+  "words two"
+  (hk-deep-force (hk-eval-expr-source "words \"hello world\""))
+  (list ":" "hello" (list ":" "world" (list "[]"))))
+
+(hk-test
+  "words leading/trailing spaces"
+  (hk-deep-force (hk-eval-expr-source "words \"  foo  bar  \""))
+  (list ":" "foo" (list ":" "bar" (list "[]"))))
+
+(hk-test
+  "words empty string"
+  (hk-deep-force (hk-eval-expr-source "words \"\""))
+  (list "[]"))
+
+;; ── lines ────────────────────────────────────────────────────
+(hk-test
+  "lines single no newline"
+  (hk-deep-force (hk-eval-expr-source "lines \"hello\""))
+  (list ":" "hello" (list "[]")))
+
+(hk-test
+  "lines two lines"
+  (hk-deep-force (hk-eval-expr-source "lines \"a\\nb\""))
+  (list ":" "a" (list ":" "b" (list "[]"))))
+
+(hk-test
+  "lines trailing newline"
+  (hk-deep-force (hk-eval-expr-source "lines \"a\\n\""))
+  (list ":" "a" (list "[]")))
+
+(hk-test
+  "lines empty string"
+  (hk-deep-force (hk-eval-expr-source "lines \"\""))
+  (list "[]"))
+
+;; ── unwords / unlines ────────────────────────────────────────
+(hk-test
+  "unwords two"
+  (hk-eval-expr-source "unwords [\"hello\", \"world\"]")
+  "hello world")
+
+(hk-test "unwords empty" (hk-eval-expr-source "unwords []") "")
+
+(hk-test "unlines two" (hk-eval-expr-source "unlines [\"a\", \"b\"]") "a\nb\n")
+
+;; ── sort / nub ───────────────────────────────────────────────
+(hk-test
+  "sort ascending"
+  (hk-deep-force (hk-eval-expr-source "sort [3,1,2]"))
+  (list ":" 1 (list ":" 2 (list ":" 3 (list "[]")))))
+
+(hk-test
+  "sort already sorted"
+  (hk-deep-force (hk-eval-expr-source "sort [1,2,3]"))
+  (list ":" 1 (list ":" 2 (list ":" 3 (list "[]")))))
+
+(hk-test
+  "nub removes duplicates"
+  (hk-deep-force (hk-eval-expr-source "nub [1,2,1,3,2]"))
+  (list ":" 1 (list ":" 2 (list ":" 3 (list "[]")))))
+
+(hk-test
+  "nub no duplicates unchanged"
+  (hk-deep-force (hk-eval-expr-source "nub [1,2,3]"))
+  (list ":" 1 (list ":" 2 (list ":" 3 (list "[]")))))
+
+;; ── splitAt ──────────────────────────────────────────────────
+(hk-test
+  "splitAt 2"
+  (hk-deep-force (hk-eval-expr-source "splitAt 2 [1,2,3,4]"))
+  (list
+    "Tuple"
+    (list ":" 1 (list ":" 2 (list "[]")))
+    (list ":" 3 (list ":" 4 (list "[]")))))
+
+(hk-test
+  "splitAt 0"
+  (hk-deep-force (hk-eval-expr-source "splitAt 0 [1,2,3]"))
+  (list
+    "Tuple"
+    (list "[]")
+    (list ":" 1 (list ":" 2 (list ":" 3 (list "[]"))))))
+
+;; ── span / break ─────────────────────────────────────────────
+(hk-test
+  "span digits"
+  (hk-deep-force (hk-eval-expr-source "span (\\x -> x < 3) [1,2,3,4]"))
+  (list
+    "Tuple"
+    (list ":" 1 (list ":" 2 (list "[]")))
+    (list ":" 3 (list ":" 4 (list "[]")))))
+
+(hk-test
+  "break digits"
+  (hk-deep-force (hk-eval-expr-source "break (\\x -> x >= 3) [1,2,3,4]"))
+  (list
+    "Tuple"
+    (list ":" 1 (list ":" 2 (list "[]")))
+    (list ":" 3 (list ":" 4 (list "[]")))))
+
+;; ── partition ────────────────────────────────────────────────
+(hk-test
+  "partition even/odd"
+  (hk-deep-force
+    (hk-eval-expr-source "partition (\\x -> x `mod` 2 == 0) [1,2,3,4,5]"))
+  (list
+    "Tuple"
+    (list ":" 2 (list ":" 4 (list "[]")))
+    (list ":" 1 (list ":" 3 (list ":" 5 (list "[]"))))))
+
+;; ── intercalate / intersperse ────────────────────────────────
+(hk-test
+  "intercalate"
+  (hk-eval-expr-source "intercalate \", \" [\"a\", \"b\", \"c\"]")
+  "a, b, c")
+
+(hk-test
+  "intersperse"
+  (hk-deep-force (hk-eval-expr-source "intersperse 0 [1,2,3]"))
+  (list
+    ":"
+    1
+    (list
+      ":"
+      0
+      (list ":" 2 (list ":" 0 (list ":" 3 (list "[]")))))))
+
+;; ── isPrefixOf / isSuffixOf / isInfixOf ──────────────────────
+(hk-test
+  "isPrefixOf True"
+  (hk-deep-force (hk-eval-expr-source "isPrefixOf [1,2] [1,2,3]"))
+  (list "True"))
+
+(hk-test
+  "isPrefixOf False"
+  (hk-deep-force (hk-eval-expr-source "isPrefixOf [2,3] [1,2,3]"))
+  (list "False"))
+
+(hk-test
+  "isSuffixOf True"
+  (hk-deep-force (hk-eval-expr-source "isSuffixOf [2,3] [1,2,3]"))
+  (list "True"))
+
+(hk-test
+  "isInfixOf True"
+  (hk-deep-force (hk-eval-expr-source "isInfixOf [2,3] [1,2,3,4]"))
+  (list "True"))
+
+(hk-test
+  "isInfixOf False"
+  (hk-deep-force (hk-eval-expr-source "isInfixOf [5,6] [1,2,3,4]"))
+  (list "False"))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-anagram.sx

@@ -0,0 +1,70 @@
+;; anagram.hs — anagram detection using sort.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-ana-src
+  "isAnagram xs ys = sort xs == sort ys\n\nhasAnagram needle haystack = any (isAnagram needle) haystack\n")
+
+(hk-test
+  "isAnagram [1,2,3] [3,2,1] True"
+  (hk-prog-val (str hk-ana-src "r = isAnagram [1,2,3] [3,2,1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isAnagram [1,2,3] [1,2,4] False"
+  (hk-prog-val (str hk-ana-src "r = isAnagram [1,2,3] [1,2,4]\n") "r")
+  (list "False"))
+
+(hk-test
+  "isAnagram [] [] True"
+  (hk-prog-val (str hk-ana-src "r = isAnagram [] []\n") "r")
+  (list "True"))
+
+(hk-test
+  "isAnagram [1] [1] True"
+  (hk-prog-val (str hk-ana-src "r = isAnagram [1] [1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isAnagram [1,2] [2,1] True"
+  (hk-prog-val (str hk-ana-src "r = isAnagram [1,2] [2,1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isAnagram [1,1,2] [2,1,1] True"
+  (hk-prog-val (str hk-ana-src "r = isAnagram [1,1,2] [2,1,1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isAnagram [1,2] [1,2,3] False"
+  (hk-prog-val (str hk-ana-src "r = isAnagram [1,2] [1,2,3]\n") "r")
+  (list "False"))
+
+(hk-test
+  "hasAnagram [1,2] [[3,4],[2,1],[5,6]] True"
+  (hk-prog-val
+    (str hk-ana-src "r = hasAnagram [1,2] [[3,4],[2,1],[5,6]]\n")
+    "r")
+  (list "True"))
+
+(hk-test
+  "hasAnagram [1,2] [[3,4],[5,6]] False"
+  (hk-prog-val (str hk-ana-src "r = hasAnagram [1,2] [[3,4],[5,6]]\n") "r")
+  (list "False"))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-binary.sx

@@ -0,0 +1,83 @@
+;; binary.hs — integer binary representation using explicit recursion.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-bin-src
+  "toBits 0 = []\ntoBits n = (n `mod` 2) : toBits (n `div` 2)\n\ntoBin 0 = [0]\ntoBin n = reverse (toBits n)\n\naddBit acc b = acc * 2 + b\nfromBin bits = foldl addBit 0 bits\n\nnumBits 0 = 1\nnumBits n = length (toBits n)\n")
+
+(hk-test
+  "toBin 0 = [0]"
+  (hk-as-list (hk-prog-val (str hk-bin-src "r = toBin 0\n") "r"))
+  (list 0))
+
+(hk-test
+  "toBin 1 = [1]"
+  (hk-as-list (hk-prog-val (str hk-bin-src "r = toBin 1\n") "r"))
+  (list 1))
+
+(hk-test
+  "toBin 2 = [1,0]"
+  (hk-as-list (hk-prog-val (str hk-bin-src "r = toBin 2\n") "r"))
+  (list 1 0))
+
+(hk-test
+  "toBin 3 = [1,1]"
+  (hk-as-list (hk-prog-val (str hk-bin-src "r = toBin 3\n") "r"))
+  (list 1 1))
+
+(hk-test
+  "toBin 4 = [1,0,0]"
+  (hk-as-list (hk-prog-val (str hk-bin-src "r = toBin 4\n") "r"))
+  (list 1 0 0))
+
+(hk-test
+  "toBin 7 = [1,1,1]"
+  (hk-as-list (hk-prog-val (str hk-bin-src "r = toBin 7\n") "r"))
+  (list 1 1 1))
+
+(hk-test
+  "toBin 8 = [1,0,0,0]"
+  (hk-as-list (hk-prog-val (str hk-bin-src "r = toBin 8\n") "r"))
+  (list 1 0 0 0))
+
+(hk-test
+  "fromBin [0] = 0"
+  (hk-prog-val (str hk-bin-src "r = fromBin [0]\n") "r")
+  0)
+
+(hk-test
+  "fromBin [1] = 1"
+  (hk-prog-val (str hk-bin-src "r = fromBin [1]\n") "r")
+  1)
+
+(hk-test
+  "fromBin [1,0,1] = 5"
+  (hk-prog-val (str hk-bin-src "r = fromBin [1,0,1]\n") "r")
+  5)
+
+(hk-test
+  "fromBin [1,1,1] = 7"
+  (hk-prog-val (str hk-bin-src "r = fromBin [1,1,1]\n") "r")
+  7)
+
+(hk-test
+  "roundtrip: fromBin (toBin 13) = 13"
+  (hk-prog-val (str hk-bin-src "r = fromBin (toBin 13)\n") "r")
+  13)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-calculator.sx

@@ -0,0 +1,55 @@
+;; calculator.hs — recursive descent expression evaluator.
+;;
+;; Exercises:
+;;   - ADTs with constructor fields: TNum Int, TOp String, R Int [Token]
+;;   - Nested constructor pattern matching: (R v (TOp "+":rest))
+;;   - let bindings in function bodies
+;;   - Integer arithmetic including `div` (backtick infix)
+;;   - Left-associative multi-level operator precedence
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-calc-src
+  "data Token = TNum Int | TOp String\ndata Result = R Int [Token]\ngetV (R v _) = v\ngetR (R _ r) = r\neval ts = getV (parseExpr ts)\nparseExpr ts = parseExprRest (parseTerm ts)\nparseExprRest (R v (TOp \"+\":rest)) =\n  let t = parseTerm rest\n  in parseExprRest (R (v + getV t) (getR t))\nparseExprRest (R v (TOp \"-\":rest)) =\n  let t = parseTerm rest\n  in parseExprRest (R (v - getV t) (getR t))\nparseExprRest r = r\nparseTerm ts = parseTermRest (parseFactor ts)\nparseTermRest (R v (TOp \"*\":rest)) =\n  let t = parseFactor rest\n  in parseTermRest (R (v * getV t) (getR t))\nparseTermRest (R v (TOp \"/\":rest)) =\n  let t = parseFactor rest\n  in parseTermRest (R (v `div` getV t) (getR t))\nparseTermRest r = r\nparseFactor (TNum n:rest) = R n rest\n")
+
+(hk-test
+  "calculator: 2 + 3 = 5"
+  (hk-prog-val
+    (str hk-calc-src "result = eval [TNum 2, TOp \"+\", TNum 3]\n")
+    "result")
+  5)
+
+(hk-test
+  "calculator: 2 + 3 * 4 = 14 (precedence)"
+  (hk-prog-val
+    (str hk-calc-src "result = eval [TNum 2, TOp \"+\", TNum 3, TOp \"*\", TNum 4]\n")
+    "result")
+  14)
+
+(hk-test
+  "calculator: 10 - 3 - 2 = 5 (left-assoc)"
+  (hk-prog-val
+    (str hk-calc-src "result = eval [TNum 10, TOp \"-\", TNum 3, TOp \"-\", TNum 2]\n")
+    "result")
+  5)
+
+(hk-test
+  "calculator: 6 / 2 * 3 = 9 (left-assoc)"
+  (hk-prog-val
+    (str hk-calc-src "result = eval [TNum 6, TOp \"/\", TNum 2, TOp \"*\", TNum 3]\n")
+    "result")
+  9)
+
+(hk-test
+  "calculator: single number"
+  (hk-prog-val
+    (str hk-calc-src "result = eval [TNum 42]\n")
+    "result")
+  42)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-collatz.sx

@@ -0,0 +1,83 @@
+;; collatz.hs — Collatz (3n+1) sequences.
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-col-src
+  "collatz 1 = [1]\ncollatz n = if n `mod` 2 == 0\n            then n : collatz (n `div` 2)\n            else n : collatz (3 * n + 1)\ncollatzLen n = length (collatz n)\n")
+
+(hk-test
+  "collatz 1 = [1]"
+  (hk-as-list (hk-prog-val (str hk-col-src "r = collatz 1\n") "r"))
+  (list 1))
+
+(hk-test
+  "collatz 2 = [2,1]"
+  (hk-as-list (hk-prog-val (str hk-col-src "r = collatz 2\n") "r"))
+  (list 2 1))
+
+(hk-test
+  "collatz 4 = [4,2,1]"
+  (hk-as-list (hk-prog-val (str hk-col-src "r = collatz 4\n") "r"))
+  (list 4 2 1))
+
+(hk-test
+  "collatz 6 starts 6,3,10"
+  (hk-as-list (hk-prog-val (str hk-col-src "r = take 3 (collatz 6)\n") "r"))
+  (list 6 3 10))
+
+(hk-test
+  "collatz 8 = [8,4,2,1]"
+  (hk-as-list (hk-prog-val (str hk-col-src "r = collatz 8\n") "r"))
+  (list 8 4 2 1))
+
+(hk-test
+  "collatzLen 1 = 1"
+  (hk-prog-val (str hk-col-src "r = collatzLen 1\n") "r")
+  1)
+
+(hk-test
+  "collatzLen 2 = 2"
+  (hk-prog-val (str hk-col-src "r = collatzLen 2\n") "r")
+  2)
+
+(hk-test
+  "collatzLen 4 = 3"
+  (hk-prog-val (str hk-col-src "r = collatzLen 4\n") "r")
+  3)
+
+(hk-test
+  "collatzLen 8 = 4"
+  (hk-prog-val (str hk-col-src "r = collatzLen 8\n") "r")
+  4)
+
+(hk-test
+  "collatzLen 16 = 5"
+  (hk-prog-val (str hk-col-src "r = collatzLen 16\n") "r")
+  5)
+
+(hk-test
+  "collatz last is always 1"
+  (hk-prog-val (str hk-col-src "r = last (collatz 27)\n") "r")
+  1)
+
+(hk-test
+  "collatz 3 = [3,10,5,16,8,4,2,1]"
+  (hk-as-list (hk-prog-val (str hk-col-src "r = collatz 3\n") "r"))
+  (list 3 10 5 16 8 4 2 1))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-either.sx

@@ -0,0 +1,83 @@
+;; either.hs — Either ADT operations via pattern matching.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-either-src
+  "safeDiv _ 0 = Left \"divide by zero\"\nsafeDiv x y = Right (x `div` y)\n\nfromRight _ (Right x) = x\nfromRight def (Left _) = def\n\nfromLeft (Left x) _ = x\nfromLeft _ def = def\n\nisRight (Right _) = True\nisRight (Left _) = False\n\nisLeft (Left _) = True\nisLeft (Right _) = False\n\nmapRight _ (Left e) = Left e\nmapRight f (Right x) = Right (f x)\n\ndouble x = x * 2\n")
+
+(hk-test
+  "safeDiv 10 2 = Right 5"
+  (hk-prog-val (str hk-either-src "r = safeDiv 10 2\n") "r")
+  (list "Right" 5))
+
+(hk-test
+  "safeDiv 7 0 = Left msg"
+  (hk-prog-val (str hk-either-src "r = safeDiv 7 0\n") "r")
+  (list "Left" "divide by zero"))
+
+(hk-test
+  "fromRight 0 (Right 42) = 42"
+  (hk-prog-val (str hk-either-src "r = fromRight 0 (Right 42)\n") "r")
+  42)
+
+(hk-test
+  "fromRight 0 (Left msg) = 0"
+  (hk-prog-val (str hk-either-src "r = fromRight 0 (Left \"err\")\n") "r")
+  0)
+
+(hk-test
+  "isRight (Right 1) = True"
+  (hk-prog-val (str hk-either-src "r = isRight (Right 1)\n") "r")
+  (list "True"))
+
+(hk-test
+  "isRight (Left x) = False"
+  (hk-prog-val (str hk-either-src "r = isRight (Left \"x\")\n") "r")
+  (list "False"))
+
+(hk-test
+  "isLeft (Left x) = True"
+  (hk-prog-val (str hk-either-src "r = isLeft (Left \"x\")\n") "r")
+  (list "True"))
+
+(hk-test
+  "isLeft (Right x) = False"
+  (hk-prog-val (str hk-either-src "r = isLeft (Right 1)\n") "r")
+  (list "False"))
+
+(hk-test
+  "mapRight double (Right 5) = Right 10"
+  (hk-prog-val (str hk-either-src "r = mapRight double (Right 5)\n") "r")
+  (list "Right" 10))
+
+(hk-test
+  "mapRight double (Left e) = Left e"
+  (hk-prog-val (str hk-either-src "r = mapRight double (Left \"err\")\n") "r")
+  (list "Left" "err"))
+
+(hk-test
+  "chain safeDiv results"
+  (hk-prog-val (str hk-either-src "r = fromRight (-1) (safeDiv 20 4)\n") "r")
+  5)
+
+(hk-test
+  "chain safeDiv error"
+  (hk-prog-val (str hk-either-src "r = fromRight (-1) (safeDiv 20 0)\n") "r")
+  -1)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-fib.sx

@@ -0,0 +1,45 @@
+;; fib.hs — infinite Fibonacci stream classic program.
+;;
+;; The canonical artefact lives at lib/haskell/tests/programs/fib.hs.
+;; The source is mirrored here as an SX string because the evaluator
+;; doesn't have read-file in the default env. If you change one, keep
+;; the other in sync — there's a runner-level cross-check against the
+;; expected first-15 list.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define hk-as-list
+  (fn (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-fib-source
+  "zipPlus (x:xs) (y:ys) = x + y : zipPlus xs ys
+zipPlus _ _ = []
+myFibs = 0 : 1 : zipPlus myFibs (tail myFibs)
+result = take 15 myFibs
+")
+
+(hk-test
+  "fib.hs — first 15 Fibonacci numbers"
+  (hk-as-list (hk-prog-val hk-fib-source "result"))
+  (list 0 1 1 2 3 5 8 13 21 34 55 89 144 233 377))
+
+;; Spot-check that the user-defined zipPlus is also reachable
+(hk-test
+  "fib.hs — zipPlus is a multi-clause user fn"
+  (hk-as-list
+    (hk-prog-val
+      (str hk-fib-source "extra = zipPlus [1, 2, 3] [10, 20, 30]\n")
+      "extra"))
+  (list 11 22 33))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-fizzbuzz.sx

@@ -0,0 +1,84 @@
+;; fizzbuzz.hs — classic FizzBuzz with guards.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-fb-src
+  "fizzbuzz n\n  | n `mod` 15 == 0 = \"FizzBuzz\"\n  | n `mod` 3  == 0 = \"Fizz\"\n  | n `mod` 5  == 0 = \"Buzz\"\n  | otherwise       = \"Other\"\n")
+
+(hk-test
+  "fizzbuzz 1 = Other"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 1\n") "r")
+  "Other")
+
+(hk-test
+  "fizzbuzz 3 = Fizz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 3\n") "r")
+  "Fizz")
+
+(hk-test
+  "fizzbuzz 5 = Buzz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 5\n") "r")
+  "Buzz")
+
+(hk-test
+  "fizzbuzz 15 = FizzBuzz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 15\n") "r")
+  "FizzBuzz")
+
+(hk-test
+  "fizzbuzz 30 = FizzBuzz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 30\n") "r")
+  "FizzBuzz")
+
+(hk-test
+  "fizzbuzz 6 = Fizz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 6\n") "r")
+  "Fizz")
+
+(hk-test
+  "fizzbuzz 10 = Buzz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 10\n") "r")
+  "Buzz")
+
+(hk-test
+  "fizzbuzz 7 = Other"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 7\n") "r")
+  "Other")
+
+(hk-test
+  "fizzbuzz 9 = Fizz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 9\n") "r")
+  "Fizz")
+
+(hk-test
+  "fizzbuzz 25 = Buzz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 25\n") "r")
+  "Buzz")
+
+(hk-test
+  "map fizzbuzz [1..5] starts Other"
+  (hk-as-list
+    (hk-prog-val (str hk-fb-src "r = map fizzbuzz [1,2,3,4,5]\n") "r"))
+  (list "Other" "Other" "Fizz" "Other" "Buzz"))
+
+(hk-test
+  "fizzbuzz 45 = FizzBuzz"
+  (hk-prog-val (str hk-fb-src "r = fizzbuzz 45\n") "r")
+  "FizzBuzz")
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-io.sx

@@ -0,0 +1,49 @@
+;; program-io.sx — tests for real IO monad (putStrLn, print, putStr).
+
+(hk-test
+  "putStrLn single line"
+  (hk-run-io "main = putStrLn \"hello\"")
+  (list "hello"))
+
+(hk-test
+  "putStrLn two lines via do"
+  (hk-run-io "main = do { putStrLn \"a\"; putStrLn \"b\" }")
+  (list "a" "b"))
+
+(hk-test "print Int" (hk-run-io "main = print 42") (list "42"))
+
+(hk-test "print Bool True" (hk-run-io "main = print True") (list "True"))
+
+(hk-test
+  "putStr collects string"
+  (hk-run-io "main = putStr \"hello\"")
+  (list "hello"))
+
+(hk-test
+  "do with let then putStrLn"
+  (hk-run-io "main = do\n  let s = \"world\"\n  putStrLn s")
+  (list "world"))
+
+(hk-test
+  "do sequence three lines"
+  (hk-run-io "main = do { putStrLn \"1\"; putStrLn \"2\"; putStrLn \"3\" }")
+  (list "1" "2" "3"))
+
+(hk-test
+  "print computed value"
+  (hk-run-io "main = print (6 * 7)")
+  (list "42"))
+
+(hk-test
+  "putStrLn returns IO unit"
+  (hk-deep-force (hk-run "main = putStrLn \"hi\""))
+  (list "IO" (list "Tuple")))
+
+(hk-test
+  "hk-run-io resets between calls"
+  (begin
+    (hk-run-io "main = putStrLn \"first\"")
+    (hk-run-io "main = putStrLn \"second\""))
+  (list "second"))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-matrix.sx

@@ -0,0 +1,84 @@
+;; matrix.hs — transpose and 2D list operations.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-mat-src
+  "transpose [] = []\ntranspose ([] : _) = []\ntranspose xss = map head xss : transpose (map tail xss)\n\nmatAdd xss yss = zipWith (zipWith (+)) xss yss\n\ndiagonal [] = []\ndiagonal xss = head (head xss) : diagonal (map tail (tail xss))\n\nrowSum = map sum\ncolSum xss = map sum (transpose xss)\n")
+
+(hk-test
+  "transpose 2x2"
+  (hk-deep-force
+    (hk-prog-val (str hk-mat-src "r = transpose [[1,2],[3,4]]\n") "r"))
+  (list
+    ":"
+    (list ":" 1 (list ":" 3 (list "[]")))
+    (list ":" (list ":" 2 (list ":" 4 (list "[]"))) (list "[]"))))
+
+(hk-test
+  "transpose 1x3"
+  (hk-deep-force
+    (hk-prog-val (str hk-mat-src "r = transpose [[1,2,3]]\n") "r"))
+  (list
+    ":"
+    (list ":" 1 (list "[]"))
+    (list
+      ":"
+      (list ":" 2 (list "[]"))
+      (list ":" (list ":" 3 (list "[]")) (list "[]")))))
+
+(hk-test
+  "transpose empty = []"
+  (hk-as-list (hk-prog-val (str hk-mat-src "r = transpose []\n") "r"))
+  (list))
+
+(hk-test
+  "rowSum [[1,2],[3,4]] = [3,7]"
+  (hk-as-list (hk-prog-val (str hk-mat-src "r = rowSum [[1,2],[3,4]]\n") "r"))
+  (list 3 7))
+
+(hk-test
+  "colSum [[1,2],[3,4]] = [4,6]"
+  (hk-as-list (hk-prog-val (str hk-mat-src "r = colSum [[1,2],[3,4]]\n") "r"))
+  (list 4 6))
+
+(hk-test
+  "matAdd [[1,2],[3,4]] [[5,6],[7,8]] = [[6,8],[10,12]]"
+  (hk-deep-force
+    (hk-prog-val
+      (str hk-mat-src "r = matAdd [[1,2],[3,4]] [[5,6],[7,8]]\n")
+      "r"))
+  (list
+    ":"
+    (list ":" 6 (list ":" 8 (list "[]")))
+    (list ":" (list ":" 10 (list ":" 12 (list "[]"))) (list "[]"))))
+
+(hk-test
+  "diagonal [[1,2],[3,4]] = [1,4]"
+  (hk-as-list
+    (hk-prog-val (str hk-mat-src "r = diagonal [[1,2],[3,4]]\n") "r"))
+  (list 1 4))
+
+(hk-test
+  "diagonal 3x3"
+  (hk-as-list
+    (hk-prog-val
+      (str hk-mat-src "r = diagonal [[1,2,3],[4,5,6],[7,8,9]]\n")
+      "r"))
+  (list 1 5 9))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-maybe.sx

@@ -0,0 +1,83 @@
+;; maybe.hs — safe operations returning Maybe values.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-maybe-src
+  "safeDiv _ 0 = Nothing\nsafeDiv x y = Just (x `div` y)\n\nsafeHead [] = Nothing\nsafeHead (x:_) = Just x\n\nfromMaybeZero Nothing = 0\nfromMaybeZero (Just x) = x\n\nmapMaybe _ Nothing = Nothing\nmapMaybe f (Just x) = Just (f x)\n\ndouble x = x * 2\n")
+
+(hk-test
+  "safeDiv 10 2 = Just 5"
+  (hk-prog-val (str hk-maybe-src "r = safeDiv 10 2\n") "r")
+  (list "Just" 5))
+
+(hk-test
+  "safeDiv 7 0 = Nothing"
+  (hk-prog-val (str hk-maybe-src "r = safeDiv 7 0\n") "r")
+  (list "Nothing"))
+
+(hk-test
+  "safeHead [1,2,3] = Just 1"
+  (hk-prog-val (str hk-maybe-src "r = safeHead [1,2,3]\n") "r")
+  (list "Just" 1))
+
+(hk-test
+  "safeHead [] = Nothing"
+  (hk-prog-val (str hk-maybe-src "r = safeHead []\n") "r")
+  (list "Nothing"))
+
+(hk-test
+  "fromMaybeZero Nothing = 0"
+  (hk-prog-val (str hk-maybe-src "r = fromMaybeZero Nothing\n") "r")
+  0)
+
+(hk-test
+  "fromMaybeZero (Just 42) = 42"
+  (hk-prog-val (str hk-maybe-src "r = fromMaybeZero (Just 42)\n") "r")
+  42)
+
+(hk-test
+  "mapMaybe double Nothing = Nothing"
+  (hk-prog-val (str hk-maybe-src "r = mapMaybe double Nothing\n") "r")
+  (list "Nothing"))
+
+(hk-test
+  "mapMaybe double (Just 5) = Just 10"
+  (hk-prog-val (str hk-maybe-src "r = mapMaybe double (Just 5)\n") "r")
+  (list "Just" 10))
+
+(hk-test
+  "chain: fromMaybeZero (safeDiv 10 2) = 5"
+  (hk-prog-val (str hk-maybe-src "r = fromMaybeZero (safeDiv 10 2)\n") "r")
+  5)
+
+(hk-test
+  "chain: fromMaybeZero (safeDiv 10 0) = 0"
+  (hk-prog-val (str hk-maybe-src "r = fromMaybeZero (safeDiv 10 0)\n") "r")
+  0)
+
+(hk-test
+  "safeDiv 100 5 = Just 20"
+  (hk-prog-val (str hk-maybe-src "r = safeDiv 100 5\n") "r")
+  (list "Just" 20))
+
+(hk-test
+  "mapMaybe double (safeDiv 6 2) = Just 6"
+  (hk-prog-val (str hk-maybe-src "r = mapMaybe double (safeDiv 6 2)\n") "r")
+  (list "Just" 6))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-nqueens.sx

@@ -0,0 +1,38 @@
+;; nqueens.hs — n-queens solver via list comprehension + where.
+;;
+;; Also exercises:
+;;   - multi-clause let/where binding (go 0 = ...; go k = ...)
+;;   - list comprehensions (desugared to concatMap)
+;;   - abs (from Prelude)
+;;   - [1..n] finite range
+;;
+;; n=8 is too slow for a 60s timeout; n=4 and n=5 run in ~17s combined.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-nq-base
+  "queens n = go n
+  where
+    go 0 = [[]]
+    go k = [q:qs | qs <- go (k - 1), q <- [1..n], safe q qs]
+safe q qs = check q qs 1
+check q [] _ = True
+check q (c:cs) d = q /= c && abs (q - c) /= d && check q cs (d + 1)
+")
+
+(hk-test
+  "nqueens: queens 4 has 2 solutions"
+  (hk-prog-val (str hk-nq-base "result = length (queens 4)\n") "result")
+  2)
+
+(hk-test
+  "nqueens: queens 5 has 10 solutions"
+  (hk-prog-val (str hk-nq-base "result = length (queens 5)\n") "result")
+  10)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-palindrome.sx

@@ -0,0 +1,86 @@
+;; palindrome.hs — palindrome check via reverse comparison.
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define hk-pal-src "isPalindrome xs = xs == reverse xs\n")
+
+(hk-test
+  "isPalindrome empty"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome []\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPalindrome single"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome [1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPalindrome [1,2,1] True"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome [1,2,1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPalindrome [1,2,3] False"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome [1,2,3]\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPalindrome [1,2,2,1] True"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome [1,2,2,1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPalindrome [1,2,3,4] False"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome [1,2,3,4]\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPalindrome five odd True"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome [1,2,3,2,1]\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPalindrome racecar True"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome \"racecar\"\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPalindrome hello False"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome \"hello\"\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPalindrome a True"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome \"a\"\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPalindrome madam True"
+  (hk-prog-val (str hk-pal-src "r = isPalindrome \"madam\"\n") "r")
+  (list "True"))
+
+(hk-test
+  "not-palindrome via map"
+  (hk-as-list
+    (hk-prog-val
+      (str hk-pal-src "r = filter isPalindrome [[1],[1,2],[1,2,1],[2,3]]\n")
+      "r"))
+  (list
+    (list ":" 1 (list "[]"))
+    (list ":" 1 (list ":" 2 (list ":" 1 (list "[]"))))))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-powers.sx

@@ -0,0 +1,78 @@
+;; powers.hs — integer exponentiation and powers-of-2 checks.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-pow-src
+  "pow _ 0 = 1\npow base n = base * pow base (n - 1)\n\npowers base k = map (pow base) [0..k]\n\nisPowerOf2 n\n  | n <= 0    = False\n  | n == 1    = True\n  | otherwise = n `mod` 2 == 0 && isPowerOf2 (n `div` 2)\n\nlog2 1 = 0\nlog2 n = 1 + log2 (n `div` 2)\n")
+
+(hk-test "pow 2 0 = 1" (hk-prog-val (str hk-pow-src "r = pow 2 0\n") "r") 1)
+
+(hk-test "pow 2 1 = 2" (hk-prog-val (str hk-pow-src "r = pow 2 1\n") "r") 2)
+
+(hk-test
+  "pow 2 8 = 256"
+  (hk-prog-val (str hk-pow-src "r = pow 2 8\n") "r")
+  256)
+
+(hk-test "pow 3 4 = 81" (hk-prog-val (str hk-pow-src "r = pow 3 4\n") "r") 81)
+
+(hk-test
+  "pow 10 3 = 1000"
+  (hk-prog-val (str hk-pow-src "r = pow 10 3\n") "r")
+  1000)
+
+(hk-test
+  "powers 2 4 = [1,2,4,8,16]"
+  (hk-as-list (hk-prog-val (str hk-pow-src "r = powers 2 4\n") "r"))
+  (list 1 2 4 8 16))
+
+(hk-test
+  "powers 3 3 = [1,3,9,27]"
+  (hk-as-list (hk-prog-val (str hk-pow-src "r = powers 3 3\n") "r"))
+  (list 1 3 9 27))
+
+(hk-test
+  "isPowerOf2 1 = True"
+  (hk-prog-val (str hk-pow-src "r = isPowerOf2 1\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPowerOf2 8 = True"
+  (hk-prog-val (str hk-pow-src "r = isPowerOf2 8\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPowerOf2 6 = False"
+  (hk-prog-val (str hk-pow-src "r = isPowerOf2 6\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPowerOf2 0 = False"
+  (hk-prog-val (str hk-pow-src "r = isPowerOf2 0\n") "r")
+  (list "False"))
+
+(hk-test "log2 1 = 0" (hk-prog-val (str hk-pow-src "r = log2 1\n") "r") 0)
+
+(hk-test "log2 8 = 3" (hk-prog-val (str hk-pow-src "r = log2 8\n") "r") 3)
+
+(hk-test
+  "log2 1024 = 10"
+  (hk-prog-val (str hk-pow-src "r = log2 1024\n") "r")
+  10)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-primes.sx

@@ -0,0 +1,83 @@
+;; primes.hs — primality testing via trial division with where clauses.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-primes-src
+  "isPrime n\n  | n < 2    = False\n  | n == 2   = True\n  | otherwise = all notDiv [2..n-1]\n  where notDiv d = n `mod` d /= 0\n\nprimes20 = filter isPrime [2..20]\n\nnextPrime n = head (filter isPrime [n+1..])\n\ncountPrimes lo hi = length (filter isPrime [lo..hi])\n")
+
+(hk-test
+  "isPrime 2 = True"
+  (hk-prog-val (str hk-primes-src "r = isPrime 2\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPrime 3 = True"
+  (hk-prog-val (str hk-primes-src "r = isPrime 3\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPrime 4 = False"
+  (hk-prog-val (str hk-primes-src "r = isPrime 4\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPrime 5 = True"
+  (hk-prog-val (str hk-primes-src "r = isPrime 5\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPrime 1 = False"
+  (hk-prog-val (str hk-primes-src "r = isPrime 1\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPrime 0 = False"
+  (hk-prog-val (str hk-primes-src "r = isPrime 0\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPrime 7 = True"
+  (hk-prog-val (str hk-primes-src "r = isPrime 7\n") "r")
+  (list "True"))
+
+(hk-test
+  "isPrime 9 = False"
+  (hk-prog-val (str hk-primes-src "r = isPrime 9\n") "r")
+  (list "False"))
+
+(hk-test
+  "isPrime 11 = True"
+  (hk-prog-val (str hk-primes-src "r = isPrime 11\n") "r")
+  (list "True"))
+
+(hk-test
+  "primes20 = [2,3,5,7,11,13,17,19]"
+  (hk-as-list (hk-prog-val (str hk-primes-src "r = primes20\n") "r"))
+  (list 2 3 5 7 11 13 17 19))
+
+(hk-test
+  "countPrimes 1 10 = 4"
+  (hk-prog-val (str hk-primes-src "r = countPrimes 1 10\n") "r")
+  4)
+
+(hk-test
+  "nextPrime 10 = 11"
+  (hk-prog-val (str hk-primes-src "r = nextPrime 10\n") "r")
+  11)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-quicksort.sx

@@ -0,0 +1,65 @@
+;; quicksort.hs — naive functional quicksort.
+
+(define
+  hk-as-list
+  (fn (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-qs-source
+  "qsort [] = []
+qsort (x:xs) = qsort smaller ++ [x] ++ qsort larger
+  where
+    smaller = filter (< x) xs
+    larger  = filter (>= x) xs
+result = qsort [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]
+")
+
+(hk-test
+  "quicksort.hs — sort a list of ints"
+  (hk-as-list (hk-prog-val hk-qs-source "result"))
+  (list 1 1 2 3 3 4 5 5 5 6 9))
+
+(hk-test
+  "quicksort.hs — empty list"
+  (hk-as-list
+    (hk-prog-val
+      (str hk-qs-source "e = qsort []\n")
+      "e"))
+  (list))
+
+(hk-test
+  "quicksort.hs — singleton"
+  (hk-as-list
+    (hk-prog-val
+      (str hk-qs-source "s = qsort [42]\n")
+      "s"))
+  (list 42))
+
+(hk-test
+  "quicksort.hs — already sorted"
+  (hk-as-list
+    (hk-prog-val
+      (str hk-qs-source "asc = qsort [1, 2, 3, 4, 5]\n")
+      "asc"))
+  (list 1 2 3 4 5))
+
+(hk-test
+  "quicksort.hs — reverse sorted"
+  (hk-as-list
+    (hk-prog-val
+      (str hk-qs-source "desc = qsort [5, 4, 3, 2, 1]\n")
+      "desc"))
+  (list 1 2 3 4 5))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-roman.sx

@@ -0,0 +1,83 @@
+;; roman.hs — convert integers to Roman numerals with guards + ++.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-rom-src
+  "toRoman 0 = \"\"\ntoRoman n\n  | n >= 1000 = \"M\"  ++ toRoman (n - 1000)\n  | n >= 900  = \"CM\" ++ toRoman (n - 900)\n  | n >= 500  = \"D\"  ++ toRoman (n - 500)\n  | n >= 400  = \"CD\" ++ toRoman (n - 400)\n  | n >= 100  = \"C\"  ++ toRoman (n - 100)\n  | n >= 90   = \"XC\" ++ toRoman (n - 90)\n  | n >= 50   = \"L\"  ++ toRoman (n - 50)\n  | n >= 40   = \"XL\" ++ toRoman (n - 40)\n  | n >= 10   = \"X\"  ++ toRoman (n - 10)\n  | n >= 9    = \"IX\" ++ toRoman (n - 9)\n  | n >= 5    = \"V\"  ++ toRoman (n - 5)\n  | n >= 4    = \"IV\" ++ toRoman (n - 4)\n  | otherwise = \"I\"  ++ toRoman (n - 1)\n")
+
+(hk-test
+  "toRoman 1 = I"
+  (hk-prog-val (str hk-rom-src "r = toRoman 1\n") "r")
+  "I")
+
+(hk-test
+  "toRoman 4 = IV"
+  (hk-prog-val (str hk-rom-src "r = toRoman 4\n") "r")
+  "IV")
+
+(hk-test
+  "toRoman 5 = V"
+  (hk-prog-val (str hk-rom-src "r = toRoman 5\n") "r")
+  "V")
+
+(hk-test
+  "toRoman 9 = IX"
+  (hk-prog-val (str hk-rom-src "r = toRoman 9\n") "r")
+  "IX")
+
+(hk-test
+  "toRoman 10 = X"
+  (hk-prog-val (str hk-rom-src "r = toRoman 10\n") "r")
+  "X")
+
+(hk-test
+  "toRoman 14 = XIV"
+  (hk-prog-val (str hk-rom-src "r = toRoman 14\n") "r")
+  "XIV")
+
+(hk-test
+  "toRoman 40 = XL"
+  (hk-prog-val (str hk-rom-src "r = toRoman 40\n") "r")
+  "XL")
+
+(hk-test
+  "toRoman 50 = L"
+  (hk-prog-val (str hk-rom-src "r = toRoman 50\n") "r")
+  "L")
+
+(hk-test
+  "toRoman 90 = XC"
+  (hk-prog-val (str hk-rom-src "r = toRoman 90\n") "r")
+  "XC")
+
+(hk-test
+  "toRoman 100 = C"
+  (hk-prog-val (str hk-rom-src "r = toRoman 100\n") "r")
+  "C")
+
+(hk-test
+  "toRoman 400 = CD"
+  (hk-prog-val (str hk-rom-src "r = toRoman 400\n") "r")
+  "CD")
+
+(hk-test
+  "toRoman 1000 = M"
+  (hk-prog-val (str hk-rom-src "r = toRoman 1000\n") "r")
+  "M")
+
+(hk-test
+  "toRoman 1994 = MCMXCIV"
+  (hk-prog-val (str hk-rom-src "r = toRoman 1994\n") "r")
+  "MCMXCIV")
+
+(hk-test
+  "toRoman 58 = LVIII"
+  (hk-prog-val (str hk-rom-src "r = toRoman 58\n") "r")
+  "LVIII")
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-sieve.sx

@@ -0,0 +1,48 @@
+;; sieve.hs — lazy sieve of Eratosthenes.
+;;
+;; The canonical artefact lives at lib/haskell/tests/programs/sieve.hs.
+;; Mirrored here as an SX string because the default eval env has no
+;; read-file. Uses filter + backtick `mod` + lazy [2..] — all of which
+;; are now wired in via Phase 3 + the mod/div additions to hk-binop.
+
+(define
+  hk-as-list
+  (fn (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-sieve-source
+  "sieve (p:xs) = p : sieve (filter (\\x -> x `mod` p /= 0) xs)
+sieve [] = []
+primes = sieve [2..]
+result = take 10 primes
+")
+
+(hk-test
+  "sieve.hs — first 10 primes"
+  (hk-as-list (hk-prog-val hk-sieve-source "result"))
+  (list 2 3 5 7 11 13 17 19 23 29))
+
+(hk-test
+  "sieve.hs — 20th prime is 71"
+  (nth
+    (hk-as-list
+      (hk-prog-val
+        (str
+          hk-sieve-source
+          "result20 = take 20 primes\n")
+        "result20"))
+    19)
+  71)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-wordcount.sx

@@ -0,0 +1,74 @@
+;; wordcount.hs — word and line counting via string splitting.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-wc-src
+  "wordCount s = length (words s)\nlineCount s = length (lines s)\ncharCount = length\n\nlongestWord s = foldl longer \"\" (words s)\n  where longer a b = if length a >= length b then a else b\n\nshortestWord s = foldl shorter (head (words s)) (words s)\n  where shorter a b = if length a <= length b then a else b\n\nuniqueWords s = nub (words s)\n")
+
+(hk-test
+  "wordCount single word"
+  (hk-prog-val (str hk-wc-src "r = wordCount \"hello\"\n") "r")
+  1)
+
+(hk-test
+  "wordCount two words"
+  (hk-prog-val (str hk-wc-src "r = wordCount \"hello world\"\n") "r")
+  2)
+
+(hk-test
+  "wordCount with extra spaces"
+  (hk-prog-val (str hk-wc-src "r = wordCount \"  foo  bar  \"\n") "r")
+  2)
+
+(hk-test
+  "wordCount empty = 0"
+  (hk-prog-val (str hk-wc-src "r = wordCount \"\"\n") "r")
+  0)
+
+(hk-test
+  "lineCount one line"
+  (hk-prog-val (str hk-wc-src "r = lineCount \"hello\"\n") "r")
+  1)
+
+(hk-test
+  "lineCount two lines"
+  (hk-prog-val (str hk-wc-src "r = lineCount \"a\\nb\"\n") "r")
+  2)
+
+(hk-test
+  "charCount \"hello\" = 5"
+  (hk-prog-val (str hk-wc-src "r = charCount \"hello\"\n") "r")
+  5)
+
+(hk-test
+  "charCount empty = 0"
+  (hk-prog-val (str hk-wc-src "r = charCount \"\"\n") "r")
+  0)
+
+(hk-test
+  "longestWord picks longest"
+  (hk-prog-val (str hk-wc-src "r = longestWord \"a bb ccc\"\n") "r")
+  "ccc")
+
+(hk-test
+  "uniqueWords removes duplicates"
+  (hk-as-list
+    (hk-prog-val (str hk-wc-src "r = uniqueWords \"a b a c b\"\n") "r"))
+  (list "a" "b" "c"))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/program-zipwith.sx

@@ -0,0 +1,74 @@
+;; zipwith.hs — zip, zipWith, unzip operations.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define
+  hk-as-list
+  (fn
+    (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-zip-src
+  "addPair (x, y) = x + y\npairSum xs ys = map addPair (zip xs ys)\n\nscaleBy k xs = map (\\x -> x * k) xs\n\ndotProduct xs ys = sum (zipWith (*) xs ys)\n\nzipIndex xs = zip [0..length xs - 1] xs\n")
+
+(hk-test
+  "zip two lists"
+  (hk-as-list (hk-prog-val (str hk-zip-src "r = zip [1,2,3] [4,5,6]\n") "r"))
+  (list (list "Tuple" 1 4) (list "Tuple" 2 5) (list "Tuple" 3 6)))
+
+(hk-test
+  "zip unequal lengths — shorter wins"
+  (hk-as-list (hk-prog-val (str hk-zip-src "r = zip [1,2] [10,20,30]\n") "r"))
+  (list (list "Tuple" 1 10) (list "Tuple" 2 20)))
+
+(hk-test
+  "zipWith (+)"
+  (hk-as-list
+    (hk-prog-val (str hk-zip-src "r = zipWith (+) [1,2,3] [10,20,30]\n") "r"))
+  (list 11 22 33))
+
+(hk-test
+  "zipWith (*)"
+  (hk-as-list
+    (hk-prog-val (str hk-zip-src "r = zipWith (*) [2,3,4] [10,10,10]\n") "r"))
+  (list 20 30 40))
+
+(hk-test
+  "dotProduct [1,2,3] [4,5,6] = 32"
+  (hk-prog-val (str hk-zip-src "r = dotProduct [1,2,3] [4,5,6]\n") "r")
+  32)
+
+(hk-test
+  "dotProduct unit vectors = 0"
+  (hk-prog-val (str hk-zip-src "r = dotProduct [1,0] [0,1]\n") "r")
+  0)
+
+(hk-test
+  "pairSum adds element-wise"
+  (hk-as-list
+    (hk-prog-val (str hk-zip-src "r = pairSum [1,2,3] [4,5,6]\n") "r"))
+  (list 5 7 9))
+
+(hk-test
+  "unzip separates pairs"
+  (hk-prog-val (str hk-zip-src "r = unzip [(1,2),(3,4),(5,6)]\n") "r")
+  (list
+    "Tuple"
+    (list ":" 1 (list ":" 3 (list ":" 5 (list "[]"))))
+    (list ":" 2 (list ":" 4 (list ":" 6 (list "[]"))))))
+
+(hk-test
+  "zip empty = []"
+  (hk-as-list (hk-prog-val (str hk-zip-src "r = zip [] [1,2,3]\n") "r"))
+  (list))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/programs/calculator.hs

@@ -0,0 +1,40 @@
+-- calculator.hs — recursive descent expression evaluator.
+--
+-- Tokens are represented as an ADT; the parser threads a [Token] list
+-- through a custom Result type so pattern matching can destructure the
+-- pair (value, remaining-tokens) directly inside constructor patterns.
+--
+-- Operator precedence: * and / bind tighter than + and -.
+-- All operators are left-associative.
+
+data Token = TNum Int | TOp String
+data Result = R Int [Token]
+
+getV (R v _) = v
+getR (R _ r) = r
+
+eval ts = getV (parseExpr ts)
+
+parseExpr ts = parseExprRest (parseTerm ts)
+
+parseExprRest (R v (TOp "+":rest)) =
+  let t = parseTerm rest
+  in parseExprRest (R (v + getV t) (getR t))
+parseExprRest (R v (TOp "-":rest)) =
+  let t = parseTerm rest
+  in parseExprRest (R (v - getV t) (getR t))
+parseExprRest r = r
+
+parseTerm ts = parseTermRest (parseFactor ts)
+
+parseTermRest (R v (TOp "*":rest)) =
+  let t = parseFactor rest
+  in parseTermRest (R (v * getV t) (getR t))
+parseTermRest (R v (TOp "/":rest)) =
+  let t = parseFactor rest
+  in parseTermRest (R (v `div` getV t) (getR t))
+parseTermRest r = r
+
+parseFactor (TNum n:rest) = R n rest
+
+result = eval [TNum 2, TOp "+", TNum 3, TOp "*", TNum 4]

lib/haskell/tests/programs/fib.hs

@@ -0,0 +1,15 @@
+-- fib.hs — infinite Fibonacci stream.
+--
+-- The classic two-line definition: `fibs` is a self-referential
+-- lazy list built by zipping itself with its own tail, summing the
+-- pair at each step. Without lazy `:` (cons cell with thunked head
+-- and tail) this would diverge before producing any output; with
+-- it, `take 15 fibs` evaluates exactly as much of the spine as
+-- demanded.
+
+zipPlus (x:xs) (y:ys) = x + y : zipPlus xs ys
+zipPlus _ _ = []
+
+myFibs = 0 : 1 : zipPlus myFibs (tail myFibs)
+
+result = take 15 myFibs

lib/haskell/tests/programs/nqueens.hs

@@ -0,0 +1,18 @@
+-- nqueens.hs — n-queens backtracking solver.
+--
+-- `queens n` returns all solutions as lists of column positions,
+-- one per row. Each call to `go k` extends all partial `(k-1)`-row
+-- solutions by one safe queen, using a list comprehension whose guard
+-- checks the new queen against all already-placed queens.
+
+queens n = go n
+  where
+    go 0 = [[]]
+    go k = [q:qs | qs <- go (k - 1), q <- [1..n], safe q qs]
+
+safe q qs = check q qs 1
+
+check q [] _     = True
+check q (c:cs) d = q /= c && abs (q - c) /= d && check q cs (d + 1)
+
+result = length (queens 8)

lib/haskell/tests/programs/quicksort.hs

@@ -0,0 +1,12 @@
+-- quicksort.hs — naive functional quicksort.
+--
+-- Partition by pivot, recurse on each half, concatenate.
+-- Uses right sections `(< x)` and `(>= x)` with filter.
+
+qsort [] = []
+qsort (x:xs) = qsort smaller ++ [x] ++ qsort larger
+  where
+    smaller = filter (< x) xs
+    larger  = filter (>= x) xs
+
+result = qsort [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]

lib/haskell/tests/programs/sieve.hs

@@ -0,0 +1,13 @@
+-- sieve.hs — lazy sieve of Eratosthenes.
+--
+-- Each recursive call to `sieve` consumes one prime `p` off the front
+-- of the input stream and produces an infinite stream of composites
+-- filtered out via `filter`. Because cons is lazy, only as much of
+-- the stream is forced as demanded by `take`.
+
+sieve (p:xs) = p : sieve (filter (\x -> x `mod` p /= 0) xs)
+sieve [] = []
+
+primes = sieve [2..]
+
+result = take 10 primes

lib/haskell/tests/runtime.sx

@@ -1,451 +1,127 @@
-;; lib/haskell/tests/runtime.sx — smoke-tests for lib/haskell/runtime.sx
-;;
-;; Uses the same hk-test framework as tests/parse.sx.
-;; Loaded by test.sh after: tokenizer.sx + runtime.sx are pre-loaded.
+;; Runtime constructor-registry tests. Built-ins are pre-registered
+;; when lib/haskell/runtime.sx loads; user types are registered by
+;; walking a parsed+desugared AST with hk-register-program! (or the
+;; `hk-load-source!` convenience).
 
-;; ---------------------------------------------------------------------------
-;; Test framework boilerplate (mirrors parse.sx)
-;; ---------------------------------------------------------------------------
+;; ── Pre-registered built-ins ──
+(hk-test "True is a con" (hk-is-con? "True") true)
+(hk-test "False is a con" (hk-is-con? "False") true)
+(hk-test "[] is a con" (hk-is-con? "[]") true)
+(hk-test ": (cons) is a con" (hk-is-con? ":") true)
+(hk-test "() is a con" (hk-is-con? "()") true)
 
-(define hk-test-pass 0)
-(define hk-test-fail 0)
-(define hk-test-fails (list))
+(hk-test "True arity 0" (hk-con-arity "True") 0)
+(hk-test ": arity 2" (hk-con-arity ":") 2)
+(hk-test "[] arity 0" (hk-con-arity "[]") 0)
+(hk-test "True type Bool" (hk-con-type "True") "Bool")
+(hk-test "False type Bool" (hk-con-type "False") "Bool")
+(hk-test ": type List" (hk-con-type ":") "List")
+(hk-test "() type Unit" (hk-con-type "()") "Unit")
 
-(define
-  (hk-test name actual expected)
-  (if
-    (= actual expected)
-    (set! hk-test-pass (+ hk-test-pass 1))
+;; ── Unknown names ──
+(hk-test "is-con? false for varid" (hk-is-con? "foo") false)
+(hk-test "arity nil for unknown" (hk-con-arity "NotACon") nil)
+(hk-test "type nil for unknown" (hk-con-type "NotACon") nil)
+
+;; ── data MyBool = Yes | No ──
+(hk-test
+  "register simple data"
   (do
-      (set! hk-test-fail (+ hk-test-fail 1))
-      (append! hk-test-fails {:actual actual :expected expected :name name}))))
+    (hk-load-source! "data MyBool = Yes | No")
+    (list
+      (hk-con-arity "Yes")
+      (hk-con-arity "No")
+      (hk-con-type "Yes")
+      (hk-con-type "No")))
+  (list 0 0 "MyBool" "MyBool"))
 
-;; ---------------------------------------------------------------------------
-;; 1. Numeric type class helpers
-;; ---------------------------------------------------------------------------
-
-(hk-test "is-integer? int" (hk-is-integer? 42) true)
-(hk-test "is-integer? float" (hk-is-integer? 1.5) false)
-(hk-test "is-float? float" (hk-is-float? 3.14) true)
-(hk-test "is-float? int" (hk-is-float? 3) false)
-(hk-test "is-num? int" (hk-is-num? 10) true)
-(hk-test "is-num? float" (hk-is-num? 1) true)
-
-(hk-test "to-float" (hk-to-float 5) 5)
-(hk-test "to-integer trunc" (hk-to-integer 3.7) 3)
-
-(hk-test "div pos pos" (hk-div 7 2) 3)
-(hk-test "div neg pos" (hk-div -7 2) -4)
-(hk-test "div pos neg" (hk-div 7 -2) -4)
-(hk-test "div neg neg" (hk-div -7 -2) 3)
-(hk-test "div exact" (hk-div 6 2) 3)
-
-(hk-test "mod pos pos" (hk-mod 10 3) 1)
-(hk-test "mod neg pos" (hk-mod -7 3) 2)
-(hk-test "rem pos pos" (hk-rem 10 3) 1)
-(hk-test "rem neg pos" (hk-rem -7 3) -1)
-
-(hk-test "abs pos" (hk-abs 5) 5)
-(hk-test "abs neg" (hk-abs -5) 5)
-(hk-test "signum pos" (hk-signum 42) 1)
-(hk-test "signum neg" (hk-signum -7) -1)
-(hk-test "signum zero" (hk-signum 0) 0)
-
-(hk-test "gcd" (hk-gcd 12 8) 4)
-(hk-test "lcm" (hk-lcm 4 6) 12)
-(hk-test "even?" (hk-even? 4) true)
-(hk-test "even? odd" (hk-even? 3) false)
-(hk-test "odd?" (hk-odd? 7) true)
-
-;; ---------------------------------------------------------------------------
-;; 2. Rational numbers
-;; ---------------------------------------------------------------------------
-
-(let
-  ((r (hk-make-rational 1 2)))
+;; ── data Maybe a = Nothing | Just a ──
+(hk-test
+  "register Maybe"
   (do
-    (hk-test "rational?" (hk-rational? r) true)
-    (hk-test "numerator" (hk-numerator r) 1)
-    (hk-test "denominator" (hk-denominator r) 2)))
+    (hk-load-source! "data Maybe a = Nothing | Just a")
+    (list
+      (hk-con-arity "Nothing")
+      (hk-con-arity "Just")
+      (hk-con-type "Nothing")
+      (hk-con-type "Just")))
+  (list 0 1 "Maybe" "Maybe"))
 
-(let
-  ((r (hk-make-rational 2 4)))
+;; ── data Either a b = Left a | Right b ──
+(hk-test
+  "register Either"
   (do
-    (hk-test "rat normalise num" (hk-numerator r) 1)
-    (hk-test "rat normalise den" (hk-denominator r) 2)))
+    (hk-load-source! "data Either a b = Left a | Right b")
+    (list
+      (hk-con-arity "Left")
+      (hk-con-arity "Right")
+      (hk-con-type "Left")
+      (hk-con-type "Right")))
+  (list 1 1 "Either" "Either"))
 
-(let
-  ((sum (hk-rational-add (hk-make-rational 1 2) (hk-make-rational 1 3))))
+;; ── Recursive data ──
+(hk-test
+  "register recursive Tree"
   (do
-    (hk-test "rat-add num" (hk-numerator sum) 5)
-    (hk-test "rat-add den" (hk-denominator sum) 6)))
+    (hk-load-source!
+      "data Tree a = Leaf | Node (Tree a) a (Tree a)")
+    (list
+      (hk-con-arity "Leaf")
+      (hk-con-arity "Node")
+      (hk-con-type "Leaf")
+      (hk-con-type "Node")))
+  (list 0 3 "Tree" "Tree"))
 
+;; ── newtype ──
 (hk-test
-  "rat-to-float"
-  (hk-rational-to-float (hk-make-rational 1 2))
-  0.5)
-(hk-test "rational? int" (hk-rational? 42) false)
-
-;; ---------------------------------------------------------------------------
-;; 3. Lazy evaluation (promises via SX delay)
-;; ---------------------------------------------------------------------------
-
-(let
-  ((p (delay 42)))
-  (hk-test "force promise" (hk-force p) 42))
-
-(hk-test "force non-promise" (hk-force 99) 99)
-
-;; ---------------------------------------------------------------------------
-;; 4. Char utilities — compare via hk-ord to avoid = on char type
-;; ---------------------------------------------------------------------------
-
-(hk-test "ord A" (hk-ord (integer->char 65)) 65)
-(hk-test "chr 65" (hk-ord (hk-chr 65)) 65)
-(hk-test "is-alpha? A" (hk-is-alpha? (integer->char 65)) true)
-(hk-test "is-alpha? 0" (hk-is-alpha? (integer->char 48)) false)
-(hk-test "is-digit? 5" (hk-is-digit? (integer->char 53)) true)
-(hk-test "is-digit? A" (hk-is-digit? (integer->char 65)) false)
-(hk-test "is-upper? A" (hk-is-upper? (integer->char 65)) true)
-(hk-test "is-upper? a" (hk-is-upper? (integer->char 97)) false)
-(hk-test "is-lower? a" (hk-is-lower? (integer->char 97)) true)
-(hk-test "is-space? spc" (hk-is-space? (integer->char 32)) true)
-(hk-test "is-space? A" (hk-is-space? (integer->char 65)) false)
-(hk-test
-  "to-upper a"
-  (hk-ord (hk-to-upper (integer->char 97)))
-  65)
-(hk-test
-  "to-lower A"
-  (hk-ord (hk-to-lower (integer->char 65)))
-  97)
-(hk-test
-  "digit-to-int 0"
-  (hk-digit-to-int (integer->char 48))
-  0)
-(hk-test
-  "digit-to-int 9"
-  (hk-digit-to-int (integer->char 57))
-  9)
-(hk-test
-  "digit-to-int a"
-  (hk-digit-to-int (integer->char 97))
-  10)
-(hk-test
-  "digit-to-int F"
-  (hk-digit-to-int (integer->char 70))
-  15)
-(hk-test "int-to-digit 0" (hk-ord (hk-int-to-digit 0)) 48)
-(hk-test "int-to-digit 10" (hk-ord (hk-int-to-digit 10)) 97)
-
-;; ---------------------------------------------------------------------------
-;; 5. Data.Set
-;; ---------------------------------------------------------------------------
-
-(hk-test "set-empty is set?" (hk-set? (hk-set-empty)) true)
-(hk-test "set-null? empty" (hk-set-null? (hk-set-empty)) true)
-
-(let
-  ((s (hk-set-singleton 42)))
+  "register newtype"
   (do
-    (hk-test "singleton member" (hk-set-member? 42 s) true)
-    (hk-test "singleton size" (hk-set-size s) 1)))
+    (hk-load-source! "newtype Age = MkAge Int")
+    (list
+      (hk-con-arity "MkAge")
+      (hk-con-type "MkAge")))
+  (list 1 "Age"))
 
-(let
-  ((s (hk-set-from-list (list 1 2 3))))
+;; ── Multiple data decls in one program ──
+(hk-test
+  "multiple data decls"
   (do
-    (hk-test "from-list member" (hk-set-member? 2 s) true)
-    (hk-test "from-list absent" (hk-set-member? 9 s) false)
-    (hk-test "from-list size" (hk-set-size s) 3)))
+    (hk-load-source!
+      "data Color = Red | Green | Blue\ndata Shape = Circle | Square\nf x = x")
+    (list
+      (hk-con-type "Red")
+      (hk-con-type "Green")
+      (hk-con-type "Blue")
+      (hk-con-type "Circle")
+      (hk-con-type "Square")))
+  (list "Color" "Color" "Color" "Shape" "Shape"))
 
-;; ---------------------------------------------------------------------------
-;; 6. Data.List
-;; ---------------------------------------------------------------------------
+;; ── Inside a module header ──
+(hk-test
+  "register from module body"
+  (do
+    (hk-load-source!
+      "module M where\ndata Pair a = Pair a a")
+    (list
+      (hk-con-arity "Pair")
+      (hk-con-type "Pair")))
+  (list 2 "Pair"))
 
-(hk-test "head" (hk-head (list 1 2 3)) 1)
+;; ── Non-data decls are ignored ──
 (hk-test
-  "tail length"
-  (len (hk-tail (list 1 2 3)))
-  2)
-(hk-test "null? empty" (hk-null? (list)) true)
-(hk-test "null? non-empty" (hk-null? (list 1)) false)
-(hk-test
-  "length"
-  (hk-length (list 1 2 3))
-  3)
-
-(hk-test
-  "take 2"
-  (hk-take 2 (list 1 2 3))
-  (list 1 2))
-(hk-test "take 0" (hk-take 0 (list 1 2)) (list))
-(hk-test
-  "take overflow"
-  (hk-take 5 (list 1 2))
-  (list 1 2))
-(hk-test
-  "drop 1"
-  (hk-drop 1 (list 1 2 3))
-  (list 2 3))
-(hk-test
-  "drop 0"
-  (hk-drop 0 (list 1 2))
-  (list 1 2))
-
-(hk-test
-  "take-while"
-  (hk-take-while
-    (fn (x) (< x 3))
-    (list 1 2 3 4))
-  (list 1 2))
-(hk-test
-  "drop-while"
-  (hk-drop-while
-    (fn (x) (< x 3))
-    (list 1 2 3 4))
-  (list 3 4))
-
-(hk-test
-  "zip"
-  (hk-zip (list 1 2) (list 3 4))
-  (list (list 1 3) (list 2 4)))
-(hk-test
-  "zip uneven"
-  (hk-zip
-    (list 1 2 3)
-    (list 4 5))
-  (list (list 1 4) (list 2 5)))
-
-(hk-test
-  "zip-with +"
-  (hk-zip-with
-    +
-    (list 1 2 3)
-    (list 10 20 30))
-  (list 11 22 33))
-
-(hk-test
-  "unzip fst"
-  (first
-    (hk-unzip
-      (list (list 1 3) (list 2 4))))
-  (list 1 2))
-(hk-test
-  "unzip snd"
-  (nth
-    (hk-unzip
-      (list (list 1 3) (list 2 4)))
-    1)
-  (list 3 4))
-
-(hk-test
-  "elem hit"
-  (hk-elem 2 (list 1 2 3))
-  true)
-(hk-test
-  "elem miss"
-  (hk-elem 9 (list 1 2 3))
+  "program with only fun-decl leaves registry unchanged for that name"
+  (do
+    (hk-load-source! "myFunctionNotACon x = x + 1")
+    (hk-is-con? "myFunctionNotACon"))
   false)
-(hk-test
-  "not-elem"
-  (hk-not-elem 9 (list 1 2 3))
-  true)
 
+;; ── Re-registering overwrites (last wins) ──
 (hk-test
-  "nub"
-  (hk-nub (list 1 2 1 3 2))
-  (list 1 2 3))
+  "re-registration overwrites the entry"
+  (do
+    (hk-load-source! "data Foo = Bar Int")
+    (hk-load-source! "data Foo = Bar Int Int")
+    (hk-con-arity "Bar"))
+  2)
 
-(hk-test
-  "sum"
-  (hk-sum (list 1 2 3 4))
-  10)
-(hk-test
-  "product"
-  (hk-product (list 1 2 3 4))
-  24)
-(hk-test
-  "maximum"
-  (hk-maximum (list 3 1 4 1 5))
-  5)
-(hk-test
-  "minimum"
-  (hk-minimum (list 3 1 4 1 5))
-  1)
-
-(hk-test
-  "concat"
-  (hk-concat
-    (list (list 1 2) (list 3 4)))
-  (list 1 2 3 4))
-(hk-test
-  "concat-map"
-  (hk-concat-map
-    (fn (x) (list x (* x x)))
-    (list 1 2 3))
-  (list 1 1 2 4 3 9))
-
-(hk-test
-  "sort"
-  (hk-sort (list 3 1 4 1 5))
-  (list 1 1 3 4 5))
-(hk-test
-  "replicate"
-  (hk-replicate 3 0)
-  (list 0 0 0))
-(hk-test "replicate 0" (hk-replicate 0 99) (list))
-
-(hk-test
-  "intersperse"
-  (hk-intersperse 0 (list 1 2 3))
-  (list 1 0 2 0 3))
-(hk-test
-  "intersperse 1"
-  (hk-intersperse 0 (list 1))
-  (list 1))
-(hk-test "intersperse empty" (hk-intersperse 0 (list)) (list))
-
-(hk-test
-  "span"
-  (hk-span
-    (fn (x) (< x 3))
-    (list 1 2 3 4))
-  (list (list 1 2) (list 3 4)))
-(hk-test
-  "break"
-  (hk-break
-    (fn (x) (>= x 3))
-    (list 1 2 3 4))
-  (list (list 1 2) (list 3 4)))
-
-(hk-test
-  "foldl"
-  (hk-foldl
-    (fn (a b) (- a b))
-    10
-    (list 1 2 3))
-  4)
-(hk-test
-  "foldr"
-  (hk-foldr cons (list) (list 1 2 3))
-  (list 1 2 3))
-
-(hk-test
-  "scanl"
-  (hk-scanl + 0 (list 1 2 3))
-  (list 0 1 3 6))
-
-;; ---------------------------------------------------------------------------
-;; 7. Maybe / Either
-;; ---------------------------------------------------------------------------
-
-(hk-test "nothing is-nothing?" (hk-is-nothing? hk-nothing) true)
-(hk-test "nothing is-just?" (hk-is-just? hk-nothing) false)
-(hk-test "just is-just?" (hk-is-just? (hk-just 42)) true)
-(hk-test "just is-nothing?" (hk-is-nothing? (hk-just 42)) false)
-(hk-test "from-just" (hk-from-just (hk-just 99)) 99)
-(hk-test
-  "from-maybe nothing"
-  (hk-from-maybe 0 hk-nothing)
-  0)
-(hk-test
-  "from-maybe just"
-  (hk-from-maybe 0 (hk-just 42))
-  42)
-(hk-test
-  "maybe nothing"
-  (hk-maybe 0 (fn (x) (* x 2)) hk-nothing)
-  0)
-(hk-test
-  "maybe just"
-  (hk-maybe 0 (fn (x) (* x 2)) (hk-just 5))
-  10)
-
-(hk-test "left is-left?" (hk-is-left? (hk-left "e")) true)
-(hk-test "right is-right?" (hk-is-right? (hk-right 42)) true)
-(hk-test "from-right" (hk-from-right (hk-right 7)) 7)
-(hk-test
-  "either left"
-  (hk-either (fn (x) (str "L" x)) (fn (x) (str "R" x)) (hk-left "err"))
-  "Lerr")
-(hk-test
-  "either right"
-  (hk-either
-    (fn (x) (str "L" x))
-    (fn (x) (str "R" x))
-    (hk-right 42))
-  "R42")
-
-;; ---------------------------------------------------------------------------
-;; 8. Tuples
-;; ---------------------------------------------------------------------------
-
-(hk-test "pair" (hk-pair 1 2) (list 1 2))
-(hk-test "fst" (hk-fst (hk-pair 3 4)) 3)
-(hk-test "snd" (hk-snd (hk-pair 3 4)) 4)
-(hk-test
-  "triple"
-  (hk-triple 1 2 3)
-  (list 1 2 3))
-(hk-test
-  "fst3"
-  (hk-fst3 (hk-triple 7 8 9))
-  7)
-(hk-test
-  "thd3"
-  (hk-thd3 (hk-triple 7 8 9))
-  9)
-
-(hk-test "curry" ((hk-curry +) 3 4) 7)
-(hk-test
-  "uncurry"
-  ((hk-uncurry (fn (a b) (* a b))) (list 3 4))
-  12)
-
-;; ---------------------------------------------------------------------------
-;; 9. String helpers
-;; ---------------------------------------------------------------------------
-
-(hk-test "words" (hk-words "hello world") (list "hello" "world"))
-(hk-test "words leading ws" (hk-words "  foo bar") (list "foo" "bar"))
-(hk-test "words empty" (hk-words "") (list))
-(hk-test "unwords" (hk-unwords (list "a" "b" "c")) "a b c")
-(hk-test "unwords single" (hk-unwords (list "x")) "x")
-
-(hk-test "lines" (hk-lines "a\nb\nc") (list "a" "b" "c"))
-(hk-test "lines single" (hk-lines "hello") (list "hello"))
-(hk-test "unlines" (hk-unlines (list "a" "b")) "a\nb\n")
-
-(hk-test "is-prefix-of yes" (hk-is-prefix-of "he" "hello") true)
-(hk-test "is-prefix-of no" (hk-is-prefix-of "wo" "hello") false)
-(hk-test "is-prefix-of eq" (hk-is-prefix-of "hi" "hi") true)
-(hk-test "is-prefix-of empty" (hk-is-prefix-of "" "hi") true)
-
-(hk-test "is-suffix-of yes" (hk-is-suffix-of "lo" "hello") true)
-(hk-test "is-suffix-of no" (hk-is-suffix-of "he" "hello") false)
-(hk-test "is-suffix-of empty" (hk-is-suffix-of "" "hi") true)
-
-(hk-test "is-infix-of yes" (hk-is-infix-of "ell" "hello") true)
-(hk-test "is-infix-of no" (hk-is-infix-of "xyz" "hello") false)
-(hk-test "is-infix-of empty" (hk-is-infix-of "" "hello") true)
-
-;; ---------------------------------------------------------------------------
-;; 10. Show
-;; ---------------------------------------------------------------------------
-
-(hk-test "show nil" (hk-show nil) "Nothing")
-(hk-test "show true" (hk-show true) "True")
-(hk-test "show false" (hk-show false) "False")
-(hk-test "show int" (hk-show 42) "42")
-(hk-test "show string" (hk-show "hi") "\"hi\"")
-(hk-test
-  "show list"
-  (hk-show (list 1 2 3))
-  "[1,2,3]")
-(hk-test "show empty list" (hk-show (list)) "[]")
-
-;; ---------------------------------------------------------------------------
-;; Summary (required by test.sh — last expression is the return value)
-;; ---------------------------------------------------------------------------
-
-(list hk-test-pass hk-test-fail)
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/seq.sx

@@ -0,0 +1,85 @@
+;; seq / deepseq tests. seq is strict in its first arg (forces to
+;; WHNF) and returns the second arg unchanged. deepseq additionally
+;; forces the first arg to normal form.
+
+(define
+  hk-prog-val
+  (fn
+    (src name)
+    (hk-deep-force (get (hk-eval-program (hk-core src)) name))))
+
+(define hk-as-list
+  (fn (xs)
+    (cond
+      ((and (list? xs) (= (first xs) "[]")) (list))
+      ((and (list? xs) (= (first xs) ":"))
+        (cons (nth xs 1) (hk-as-list (nth xs 2))))
+      (:else xs))))
+
+(define
+  hk-eval-list
+  (fn (src) (hk-as-list (hk-eval-expr-source src))))
+
+;; ── seq returns its second arg ──
+(hk-test
+  "seq with primitive first arg"
+  (hk-eval-expr-source "seq 1 99")
+  99)
+
+(hk-test
+  "seq forces first arg via let"
+  (hk-eval-expr-source "let x = 1 + 2 in seq x x")
+  3)
+
+(hk-test
+  "seq second arg is whatever shape"
+  (hk-eval-expr-source "seq 0 \"hello\"")
+  "hello")
+
+;; ── seq enables previously-lazy bottom to be forced ──
+;; Without seq the let-binding `x = error …` is never forced;
+;; with seq it must be forced because seq is strict in its first
+;; argument. We don't run that error case here (it would terminate
+;; the test), but we do verify the negative — that without seq,
+;; the bottom bound is never demanded.
+(hk-test
+  "lazy let — bottom never forced when unused"
+  (hk-eval-expr-source "let x = error \"never\" in 42")
+  42)
+
+;; ── deepseq forces nested structure ──
+(hk-test
+  "deepseq with finite list"
+  (hk-eval-expr-source "deepseq [1, 2, 3] 7")
+  7)
+
+(hk-test
+  "deepseq with constructor value"
+  (hk-eval-expr-source "deepseq (Just 5) 11")
+  11)
+
+(hk-test
+  "deepseq with tuple"
+  (hk-eval-expr-source "deepseq (1, 2) 13")
+  13)
+
+;; ── seq + arithmetic ──
+(hk-test
+  "seq used inside arithmetic doesn't poison the result"
+  (hk-eval-expr-source "(seq 1 5) + (seq 2 7)")
+  12)
+
+;; ── seq in user code ──
+(hk-test
+  "seq via fun-clause"
+  (hk-prog-val
+    "f x = seq x (x + 1)\nresult = f 10"
+    "result")
+  11)
+
+(hk-test
+  "seq sequences list construction"
+  (hk-eval-list "[seq 1 10, seq 2 20]")
+  (list 10 20))
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/stdlib.sx

@@ -0,0 +1,151 @@
+;; stdlib.sx — tests for standard-library functions added in Phase 5:
+;; Eq/Ord, Show, Num, Functor, Monad, Applicative, plus common Prelude.
+
+(define
+  hk-t
+  (fn
+    (lbl src expected)
+    (hk-test lbl (hk-deep-force (hk-run src)) expected)))
+
+(define
+  hk-ts
+  (fn
+    (lbl src expected)
+    (hk-test
+      lbl
+      (hk-deep-force (hk-run (str "main = show (" src ")")))
+      expected)))
+
+;; ── Ord ──────────────────────────────────────────────────────
+(hk-test
+  "compare lt"
+  (hk-deep-force (hk-run "main = compare 1 2"))
+  (list "LT"))
+(hk-test
+  "compare eq"
+  (hk-deep-force (hk-run "main = compare 3 3"))
+  (list "EQ"))
+(hk-test
+  "compare gt"
+  (hk-deep-force (hk-run "main = compare 9 5"))
+  (list "GT"))
+(hk-test "min" (hk-deep-force (hk-run "main = min 3 5")) 3)
+(hk-test "max" (hk-deep-force (hk-run "main = max 3 5")) 5)
+
+;; ── Show ─────────────────────────────────────────────────────
+(hk-ts "show int" "42" "42")
+(hk-ts "show neg" "negate 7" "-7")
+(hk-ts "show bool T" "True" "True")
+(hk-ts "show bool F" "False" "False")
+(hk-ts "show list" "[1,2,3]" "[1, 2, 3]")
+(hk-ts "show Just" "Just 5" "(Just 5)")
+(hk-ts "show Nothing" "Nothing" "Nothing")
+(hk-ts "show LT" "LT" "LT")
+(hk-ts "show tuple" "(1, True)" "(1, True)")
+
+;; ── Num extras ───────────────────────────────────────────────
+(hk-test "signum pos" (hk-deep-force (hk-run "main = signum 5")) 1)
+(hk-test
+  "signum neg"
+  (hk-deep-force (hk-run "main = signum (negate 3)"))
+  (- 0 1))
+(hk-test "signum zero" (hk-deep-force (hk-run "main = signum 0")) 0)
+(hk-test "fromIntegral" (hk-deep-force (hk-run "main = fromIntegral 7")) 7)
+
+;; ── foldr / foldl ────────────────────────────────────────────
+(hk-test "foldr sum" (hk-deep-force (hk-run "main = foldr (+) 0 [1,2,3]")) 6)
+(hk-test "foldl sum" (hk-deep-force (hk-run "main = foldl (+) 0 [1,2,3]")) 6)
+(hk-test "foldl1" (hk-deep-force (hk-run "main = foldl1 (+) [1,2,3,4]")) 10)
+(hk-test
+  "foldr cons"
+  (hk-deep-force (hk-run "main = show (foldr (:) [] [1,2,3])"))
+  "[1, 2, 3]")
+
+;; ── List ops ─────────────────────────────────────────────────
+(hk-test
+  "reverse"
+  (hk-deep-force (hk-run "main = show (reverse [1,2,3])"))
+  "[3, 2, 1]")
+(hk-test "null []" (hk-deep-force (hk-run "main = null []")) (list "True"))
+(hk-test
+  "null xs"
+  (hk-deep-force (hk-run "main = null [1]"))
+  (list "False"))
+(hk-test
+  "elem yes"
+  (hk-deep-force (hk-run "main = elem 2 [1,2,3]"))
+  (list "True"))
+(hk-test
+  "elem no"
+  (hk-deep-force (hk-run "main = elem 9 [1,2,3]"))
+  (list "False"))
+(hk-test
+  "zip"
+  (hk-deep-force (hk-run "main = show (zip [1,2] [3,4])"))
+  "[(1, 3), (2, 4)]")
+(hk-test "sum" (hk-deep-force (hk-run "main = sum [1,2,3,4,5]")) 15)
+(hk-test "product" (hk-deep-force (hk-run "main = product [1,2,3,4]")) 24)
+(hk-test "maximum" (hk-deep-force (hk-run "main = maximum [3,1,9,2]")) 9)
+(hk-test "minimum" (hk-deep-force (hk-run "main = minimum [3,1,9,2]")) 1)
+(hk-test
+  "any yes"
+  (hk-deep-force (hk-run "main = any (\\x -> x > 3) [1,2,5]"))
+  (list "True"))
+(hk-test
+  "any no"
+  (hk-deep-force (hk-run "main = any (\\x -> x > 9) [1,2,5]"))
+  (list "False"))
+(hk-test
+  "all yes"
+  (hk-deep-force (hk-run "main = all (\\x -> x > 0) [1,2,5]"))
+  (list "True"))
+(hk-test
+  "all no"
+  (hk-deep-force (hk-run "main = all (\\x -> x > 3) [1,2,5]"))
+  (list "False"))
+
+;; ── Higher-order ─────────────────────────────────────────────
+(hk-test "flip" (hk-deep-force (hk-run "main = flip (-) 3 10")) 7)
+(hk-test "const" (hk-deep-force (hk-run "main = const 42 True")) 42)
+
+;; ── Functor ──────────────────────────────────────────────────
+(hk-test
+  "fmap list"
+  (hk-deep-force (hk-run "main = show (fmap (+1) [1,2,3])"))
+  "[2, 3, 4]")
+
+;; ── Monad / Applicative ──────────────────────────────────────
+(hk-test "return" (hk-deep-force (hk-run "main = return 7")) (list "IO" 7))
+(hk-test "pure" (hk-deep-force (hk-run "main = pure 7")) (list "IO" 7))
+(hk-test
+  "when T"
+  (hk-deep-force (hk-run "main = when True (return 1)"))
+  (list "IO" 1))
+(hk-test
+  "when F"
+  (hk-deep-force (hk-run "main = when False (return 1)"))
+  (list "IO" (list "()")))
+(hk-test
+  "unless F"
+  (hk-deep-force (hk-run "main = unless False (return 2)"))
+  (list "IO" 2))
+
+;; ── lookup / maybe / either ─────────────────────────────────
+(hk-test
+  "lookup hit"
+  (hk-deep-force (hk-run "main = show (lookup 2 [(1,10),(2,20)])"))
+  "(Just 20)")
+(hk-test
+  "lookup miss"
+  (hk-deep-force (hk-run "main = show (lookup 9 [(1,10)])"))
+  "Nothing")
+(hk-test
+  "maybe def"
+  (hk-deep-force (hk-run "main = maybe 0 (+1) Nothing"))
+  0)
+(hk-test
+  "maybe just"
+  (hk-deep-force (hk-run "main = maybe 0 (+1) (Just 5)"))
+  6)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/haskell/tests/typecheck.sx

@@ -0,0 +1,82 @@
+;; typecheck.sx — tests for hk-typecheck / hk-run-typed.
+;; Verifies that untypeable programs are rejected and well-typed programs pass.
+
+(define hk-str-has? (fn (s sub) (>= (index-of s sub) 0)))
+
+;; Helper: expect a type error containing `sub`
+(define
+  hk-tc-err
+  (fn
+    (label src sub)
+    (hk-test
+      label
+      (guard
+        (e (#t (hk-str-has? e sub)))
+        (begin (hk-run-typed src) false))
+      true)))
+
+;; ─── Valid programs pass through ─────────────────────────────────────────────
+(hk-test "typed ok: simple arithmetic" (hk-run-typed "main = 1 + 2") 3)
+
+(hk-test "typed ok: boolean" (hk-run-typed "main = True") (list "True"))
+
+(hk-test "typed ok: let binding" (hk-run-typed "main = let x = 1 in x + 2") 3)
+
+(hk-test
+  "typed ok: two independent fns"
+  (hk-run-typed "f x = x + 1\nmain = f 5")
+  6)
+
+;; ─── Untypeable programs are rejected ────────────────────────────────────────
+;; Adding Int and Bool is a unification failure.
+(hk-tc-err "reject: Int + Bool mentions Int" "main = 1 + True" "Int")
+(hk-tc-err "reject: Int + Bool mentions Bool" "main = 1 + True" "Bool")
+
+;; Condition of if must be Bool.
+(hk-tc-err "reject: if non-bool condition" "main = if 1 then 2 else 3" "Bool")
+
+;; Unbound variable.
+(hk-tc-err "reject: unbound variable" "main = unknownVar + 1" "unknownVar")
+
+;; Function body type error: applying non-function.
+(hk-tc-err "reject: apply non-function" "f x = 1 x" "Int")
+
+(define prog-sig1 (hk-core "f :: Int -> Int\nf x = x + 1"))
+
+(define prog-sig2 (hk-core "f :: Bool -> Bool\nf x = x + 1"))
+
+(define prog-sig3 (hk-core "id :: a -> a\nid x = x"))
+
+(hk-test
+  "sig ok: Int->Int accepted"
+  (first (nth (hk-infer-prog prog-sig1 (hk-type-env0)) 0))
+  "ok")
+
+(hk-test
+  "sig fail: Bool->Bool rejected"
+  (first (nth (hk-infer-prog prog-sig2 (hk-type-env0)) 0))
+  "err")
+
+(hk-test
+  "sig fail: error mentions mismatch"
+  (hk-str-has?
+    (nth (nth (hk-infer-prog prog-sig2 (hk-type-env0)) 0) 1)
+    "mismatch")
+  true)
+
+(hk-test
+  "sig ok: polymorphic a->a accepted"
+  (first (nth (hk-infer-prog prog-sig3 (hk-type-env0)) 0))
+  "ok")
+
+(hk-tc-err
+  "run-typed sig fail: Bool declared, Int inferred"
+  "main :: Bool\nmain = 1 + 2"
+  "mismatch")
+
+(hk-test
+  "run-typed sig ok: Int declared matches"
+  (hk-run-typed "main :: Int\nmain = 1 + 2")
+  3)
+
+{:fails hk-test-fails :pass hk-test-pass :fail hk-test-fail}

lib/hyperscript/integration.sx

@@ -19,6 +19,7 @@
       (define
         reserved
         (list
+          (quote beingTold)
           (quote me)
           (quote it)
           (quote event)
@@ -65,7 +66,10 @@
                   (list (quote me))
                   (list
                     (quote let)
-                    (list (list (quote it) nil) (list (quote event) nil))
+                    (list
+                      (list (quote beingTold) (quote me))
+                      (list (quote it) nil)
+                      (list (quote event) nil))
                     guarded))))))))))
 
 ;; ── Activate a single element ───────────────────────────────────
@@ -73,23 +77,82 @@
 ;; Marks the element to avoid double-activation.
 
 (define
-  hs-activate!
+  hs-register-scripts!
   (fn
-    (el)
-    (let
-      ((src (dom-get-attr el "_")) (prev (dom-get-data el "hs-script")))
+    ()
+    (for-each
+      (fn
+        (script)
         (when
-        (and src (not (= src prev)))
-        (hs-log-event! "hyperscript:init")
-        (dom-set-data el "hs-script" src)
-        (dom-set-data el "hs-active" true)
-        (dom-set-attr el "data-hyperscript-powered" "true")
-        (let ((handler (hs-handler src))) (handler el))))))
+          (not (dom-get-data script "hs-script-loaded"))
+          (let
+            ((src (host-get script "innerHTML")))
+            (guard
+              (_e (true nil))
+              (let
+                ((handler (eval-expr-cek (hs-to-sx-from-source src))))
+                (handler (dom-body)))))))
+      (hs-query-all "script[type=text/hyperscript]"))))
 
 ;; ── Boot: scan entire document ──────────────────────────────────
 ;; Called once at page load. Finds all elements with _ attribute,
 ;; compiles their hyperscript, and activates them.
 
+(define
+  hs-scripting-disabled?
+  (fn
+    (el)
+    (if
+      (= el nil)
+      false
+      (if
+        (dom-get-attr el "disable-scripting")
+        true
+        (hs-scripting-disabled? (dom-parent el))))))
+
+;; ── Boot subtree: for dynamic content ───────────────────────────
+;; Called after HTMX swaps or dynamic DOM insertion.
+;; Only activates elements within the given root.
+
+(define
+  hs-activate!
+  (fn
+    (el)
+    (do
+      (hs-register-scripts!)
+      (let
+        ((src (dom-get-attr el "_")) (prev (dom-get-data el "hs-script")))
+        (when
+          (and src (not (= src prev)) (not (hs-scripting-disabled? el)))
+          (when
+            (dom-dispatch el "hyperscript:before:init" nil)
+            (hs-log-event! "hyperscript:init")
+            (dom-set-data el "hs-script" src)
+            (dom-set-data el "hs-active" true)
+            (dom-set-attr el "data-hyperscript-powered" "true")
+            (host-set! (host-global "window") "__hs_current_me" el)
+            (guard
+              (_e
+                (true
+                  (do
+                    (dom-dispatch el "hyperscript:parse-error" {:errors (list _e)})
+                    nil)))
+              (let
+                ((handler (hs-handler src)))
+                (let
+                  ((el-type (dom-get-attr el "type"))
+                    (comp-name (dom-get-attr el "component")))
+                  (let
+                    ((safe-handler (fn (e) (host-call-fn handler (list e)))))
+                    (if
+                      (= el-type "text/hyperscript-template")
+                      (for-each
+                        safe-handler
+                        (hs-query-all (or comp-name "")))
+                      (safe-handler el))))))
+            (host-set! (host-global "window") "__hs_current_me" nil)
+            (dom-dispatch el "hyperscript:after:init" nil)))))))
+
 (define
   hs-deactivate!
   (fn
@@ -101,10 +164,6 @@
       (dom-set-data el "hs-active" false)
       (dom-set-data el "hs-script" nil))))
 
-;; ── Boot subtree: for dynamic content ───────────────────────────
-;; Called after HTMX swaps or dynamic DOM insertion.
-;; Only activates elements within the given root.
-
 (define
   hs-boot!
   (fn

lib/hyperscript/tokenizer.sx

@@ -28,6 +28,27 @@
 
 (define hs-ws? (fn (c) (or (= c " ") (= c "\t") (= c "\n") (= c "\r"))))
 
+(define
+  hs-hex-digit?
+  (fn
+    (c)
+    (or
+      (and (>= c "0") (<= c "9"))
+      (and (>= c "a") (<= c "f"))
+      (and (>= c "A") (<= c "F")))))
+
+(define
+  hs-hex-val
+  (fn
+    (c)
+    (let
+      ((code (char-code c)))
+      (cond
+        ((and (>= code 48) (<= code 57))  (- code 48))
+        ((and (>= code 65) (<= code 70))  (- code 55))
+        ((and (>= code 97) (<= code 102)) (- code 87))
+        (true 0)))))
+
 ;; ── Keyword set ───────────────────────────────────────────────────
 
 (define
@@ -110,6 +131,7 @@
     "append"
     "settle"
     "transition"
+    "view"
     "over"
     "closest"
     "next"
@@ -187,7 +209,8 @@
     "using"
     "giving"
     "ask"
-    "answer"))
+    "answer"
+    "bind"))
 
 (define hs-keyword? (fn (word) (some (fn (k) (= k word)) hs-keywords)))
 
@@ -235,10 +258,15 @@
         read-number
         (fn
           (start)
+          (define
+            read-int
+            (fn
+              ()
               (when
                 (and (< pos src-len) (hs-digit? (hs-cur)))
                 (hs-advance! 1)
-            (read-number start))
+                (read-int))))
+          (read-int)
           (when
             (and
               (< pos src-len)
@@ -246,15 +274,7 @@
               (< (+ pos 1) src-len)
               (hs-digit? (hs-peek 1)))
             (hs-advance! 1)
-            (define
-              read-frac
-              (fn
-                ()
-                (when
-                  (and (< pos src-len) (hs-digit? (hs-cur)))
-                  (hs-advance! 1)
-                  (read-frac))))
-            (read-frac))
+            (read-int))
           (do
             (when
               (and
@@ -272,15 +292,7 @@
                   (< pos src-len)
                   (or (= (hs-cur) "+") (= (hs-cur) "-")))
                 (hs-advance! 1))
-              (define
-                read-exp-digits
-                (fn
-                  ()
-                  (when
-                    (and (< pos src-len) (hs-digit? (hs-cur)))
-                    (hs-advance! 1)
-                    (read-exp-digits))))
-              (read-exp-digits))
+              (read-int))
             (let
               ((num-end pos))
               (when
@@ -308,7 +320,7 @@
                 ()
                 (cond
                   (>= pos src-len)
-                  nil
+                  (error "Unterminated string")
                   (= (hs-cur) "\\")
                   (do
                     (hs-advance! 1)
@@ -318,15 +330,47 @@
                         ((ch (hs-cur)))
                         (cond
                           (= ch "n")
-                          (append! chars "\n")
+                          (do (append! chars "\n") (hs-advance! 1))
                           (= ch "t")
-                          (append! chars "\t")
+                          (do (append! chars "\t") (hs-advance! 1))
+                          (= ch "r")
+                          (do (append! chars "\r") (hs-advance! 1))
+                          (= ch "b")
+                          (do
+                            (append! chars (char-from-code 8))
+                            (hs-advance! 1))
+                          (= ch "f")
+                          (do
+                            (append! chars (char-from-code 12))
+                            (hs-advance! 1))
+                          (= ch "v")
+                          (do
+                            (append! chars (char-from-code 11))
+                            (hs-advance! 1))
                           (= ch "\\")
-                          (append! chars "\\")
+                          (do (append! chars "\\") (hs-advance! 1))
                           (= ch quote-char)
-                          (append! chars quote-char)
-                          :else (do (append! chars "\\") (append! chars ch)))
-                        (hs-advance! 1)))
+                          (do (append! chars quote-char) (hs-advance! 1))
+                          (= ch "x")
+                          (do
+                            (hs-advance! 1)
+                            (if
+                              (and
+                                (< (+ pos 1) src-len)
+                                (hs-hex-digit? (hs-cur))
+                                (hs-hex-digit? (hs-peek 1)))
+                              (let
+                                ((d1 (hs-hex-val (hs-cur)))
+                                  (d2 (hs-hex-val (hs-peek 1))))
+                                (append!
+                                  chars
+                                  (char-from-code (+ (* d1 16) d2)))
+                                (hs-advance! 2))
+                              (error "Invalid hexadecimal escape: \\x")))
+                          :else (do
+                            (append! chars "\\")
+                            (append! chars ch)
+                            (hs-advance! 1)))))
                     (loop))
                   (= (hs-cur) quote-char)
                   (hs-advance! 1)
@@ -413,27 +457,68 @@
         read-class-name
         (fn
           (start)
-          (when
-            (and
-              (< pos src-len)
-              (or
-                (hs-ident-char? (hs-cur))
-                (= (hs-cur) ":")
-                (= (hs-cur) "[")
-                (= (hs-cur) "]")))
+          (define
+            build-name
+            (fn
+              (acc depth)
+              (cond
+                ((and (< pos src-len) (= (hs-cur) "\\") (< (+ pos 1) src-len))
+                  (do
                     (hs-advance! 1)
-            (read-class-name start))
-          (slice src start pos)))
+                    (let
+                      ((c (hs-cur)))
+                      (hs-advance! 1)
+                      (build-name (str acc c) depth))))
+                ((and (< pos src-len) (= (hs-cur) "["))
+                  (do
+                    (let
+                      ((c (hs-cur)))
+                      (hs-advance! 1)
+                      (build-name (str acc c) (+ depth 1)))))
+                ((and (< pos src-len) (= (hs-cur) "]"))
+                  (do
+                    (let
+                      ((c (hs-cur)))
+                      (hs-advance! 1)
+                      (build-name
+                        (str acc c)
+                        (if (> depth 0) (- depth 1) 0)))))
+                ((and (< pos src-len) (> depth 0) (or (= (hs-cur) "(") (= (hs-cur) ")")))
+                  (do
+                    (let
+                      ((c (hs-cur)))
+                      (hs-advance! 1)
+                      (build-name (str acc c) depth))))
+                ((and (< pos src-len) (or (hs-ident-char? (hs-cur)) (= (hs-cur) ":") (= (hs-cur) "&")))
+                  (do
+                    (let
+                      ((c (hs-cur)))
+                      (hs-advance! 1)
+                      (build-name (str acc c) depth))))
+                (true acc))))
+          (build-name "" 0)))
       (define
         hs-emit!
         (fn
           (type value start)
-          (append! tokens (hs-make-token type value start))))
+          (let
+            ((tok (hs-make-token type value start))
+              (end-pos
+                (max pos (+ start (if (nil? value) 0 (len (str value)))))))
+            (do
+              (dict-set! tok "end" end-pos)
+              (dict-set! tok "line" (len (split (slice src 0 start) "\n")))
+              (append! tokens tok)))))
       (define
         scan!
         (fn
           ()
+          (let
+            ((ws-start pos))
             (skip-ws!)
+            (when
+              (and (> (len tokens) 0) (> pos ws-start))
+              (hs-emit! "whitespace" (slice src ws-start pos) ws-start)))
           (when
             (< pos src-len)
             (let
@@ -453,10 +538,26 @@
                     (= (hs-peek 1) "#")
                     (= (hs-peek 1) "[")
                     (= (hs-peek 1) "*")
-                    (= (hs-peek 1) ":")))
+                    (= (hs-peek 1) ":")
+                    (= (hs-peek 1) "$")))
                 (do (hs-emit! "selector" (read-selector) start) (scan!))
                 (and (= ch ".") (< (+ pos 1) src-len) (= (hs-peek 1) "."))
                 (do (hs-emit! "op" ".." start) (hs-advance! 2) (scan!))
+                (and
+                  (= ch ".")
+                  (< (+ pos 1) src-len)
+                  (or
+                    (hs-letter? (hs-peek 1))
+                    (= (hs-peek 1) "-")
+                    (= (hs-peek 1) "_"))
+                  (> (len tokens) 0)
+                  (let
+                    ((lt (dict-get (nth tokens (- (len tokens) 1)) :type)))
+                    (or
+                      (= lt "paren-close")
+                      (= lt "brace-close")
+                      (= lt "bracket-close"))))
+                (do (hs-emit! "dot" "." start) (hs-advance! 1) (scan!))
                 (and
                   (= ch ".")
                   (< (+ pos 1) src-len)
@@ -468,6 +569,18 @@
                   (hs-advance! 1)
                   (hs-emit! "class" (read-class-name pos) start)
                   (scan!))
+                (and
+                  (= ch "#")
+                  (< (+ pos 1) src-len)
+                  (hs-ident-start? (hs-peek 1))
+                  (> (len tokens) 0)
+                  (let
+                    ((lt (dict-get (nth tokens (- (len tokens) 1)) :type)))
+                    (or
+                      (= lt "paren-close")
+                      (= lt "brace-close")
+                      (= lt "bracket-close"))))
+                (do (hs-emit! "op" "#" start) (hs-advance! 1) (scan!))
                 (and
                   (= ch "#")
                   (< (+ pos 1) src-len)
@@ -536,10 +649,12 @@
                 (do
                   (let
                     ((word (read-ident start)))
+                    (let
+                      ((full-word (if (and (< pos src-len) (= (hs-cur) "'") (< (+ pos 1) src-len) (hs-letter? (hs-peek 1)) (not (and (= (hs-peek 1) "s") (or (>= (+ pos 2) src-len) (not (hs-ident-char? (hs-peek 2))))))) (do (hs-advance! 1) (str word "'" (read-ident pos))) word)))
                       (hs-emit!
-                      (if (hs-keyword? word) "keyword" "ident")
-                      word
-                      start))
+                        (if (hs-keyword? full-word) "keyword" "ident")
+                        full-word
+                        start)))
                   (scan!))
                 (and
                   (or (= ch "=") (= ch "!") (= ch "<") (= ch ">"))
@@ -620,7 +735,82 @@
                 (do (hs-emit! "colon" ":" start) (hs-advance! 1) (scan!))
                 (= ch "|")
                 (do (hs-emit! "op" "|" start) (hs-advance! 1) (scan!))
+                (= ch "&")
+                (do (hs-emit! "op" "&" start) (hs-advance! 1) (scan!))
+                (= ch "#")
+                (do (hs-emit! "op" "#" start) (hs-advance! 1) (scan!))
+                (= ch "?")
+                (do (hs-emit! "op" "?" start) (hs-advance! 1) (scan!))
+                (= ch ";")
+                (do (hs-emit! "op" ";" start) (hs-advance! 1) (scan!))
                 :else (do (hs-advance! 1) (scan!)))))))
       (scan!)
       (hs-emit! "eof" nil pos)
       tokens)))
+
+;; ── Template-mode tokenizer (E37 API) ────────────────────────────────
+;; Used by hs-tokens-of when :template flag is set.
+;; Emits outer " chars as single STRING tokens; ${ ... } as $ { <inner-tokens> };
+;; inner content is tokenized with the regular hs-tokenize.
+
+(define
+  hs-tokenize-template
+  (fn
+    (src)
+    (let
+      ((tokens (list)) (pos 0) (src-len (len src)))
+      (define t-cur (fn () (if (< pos src-len) (nth src pos) nil)))
+      (define t-peek (fn (n) (if (< (+ pos n) src-len) (nth src (+ pos n)) nil)))
+      (define t-advance! (fn (n) (set! pos (+ pos n))))
+      (define t-emit! (fn (type value) (append! tokens (hs-make-token type value pos))))
+      (define
+        scan-to-close!
+        (fn
+          (depth)
+          (when
+            (and (< pos src-len) (> depth 0))
+            (cond
+              (= (t-cur) "{")
+              (do (t-advance! 1) (scan-to-close! (+ depth 1)))
+              (= (t-cur) "}")
+              (when (> (- depth 1) 0) (t-advance! 1) (scan-to-close! (- depth 1)))
+              :else (do (t-advance! 1) (scan-to-close! depth))))))
+      (define
+        scan-template!
+        (fn
+          ()
+          (when
+            (< pos src-len)
+            (let
+              ((ch (t-cur)))
+              (cond
+                (= ch "\"")
+                (do (t-emit! "string" "\"") (t-advance! 1) (scan-template!))
+                (and (= ch "$") (= (t-peek 1) "{"))
+                (do
+                  (t-emit! "op" "$")
+                  (t-advance! 1)
+                  (t-emit! "brace-open" "{")
+                  (t-advance! 1)
+                  (let
+                    ((inner-start pos))
+                    (scan-to-close! 1)
+                    (let
+                      ((inner-src (slice src inner-start pos))
+                       (inner-toks (hs-tokenize inner-src)))
+                      (for-each
+                        (fn (tok)
+                          (when (not (= (get tok "type") "eof"))
+                            (append! tokens tok)))
+                        inner-toks))
+                    (t-emit! "brace-close" "}")
+                    (when (< pos src-len) (t-advance! 1)))
+                  (scan-template!))
+                (= ch "$")
+                (do (t-emit! "op" "$") (t-advance! 1) (scan-template!))
+                (hs-ws? ch)
+                (do (t-advance! 1) (scan-template!))
+                :else (do (t-advance! 1) (scan-template!)))))))
+      (scan-template!)
+      (t-emit! "eof" nil)
+      tokens)))

lib/prolog/compiler.sx

@@ -0,0 +1,176 @@
+;; lib/prolog/compiler.sx — clause compiler: parse-AST clauses → SX closures
+;;
+;; Each compiled clause is a lambda (fn (goal trail db cut-box k) bool)
+;; that creates fresh vars, builds the instantiated head/body, and calls
+;; pl-unify! + pl-solve! directly — no AST walk at solve time.
+;;
+;; Usage:
+;;   (pl-db-load! db (pl-parse src))
+;;   (pl-compile-db! db)
+;;   ; pl-solve-user! in runtime.sx automatically prefers compiled clauses
+;;   (pl-solve-once! db goal trail)
+
+;; Collect unique variable names from a parse-AST clause into a dict.
+(define
+  pl-cmp-vars-into!
+  (fn
+    (ast seen)
+    (cond
+      ((not (list? ast)) nil)
+      ((empty? ast) nil)
+      ((= (first ast) "var")
+        (let
+          ((name (nth ast 1)))
+          (when
+            (and (not (= name "_")) (not (dict-has? seen name)))
+            (dict-set! seen name true))))
+      ((= (first ast) "compound")
+        (for-each (fn (a) (pl-cmp-vars-into! a seen)) (nth ast 2)))
+      ((= (first ast) "clause")
+        (begin
+          (pl-cmp-vars-into! (nth ast 1) seen)
+          (pl-cmp-vars-into! (nth ast 2) seen))))))
+
+;; Return list of unique var names in a clause (head + body, excluding _).
+(define
+  pl-cmp-collect-vars
+  (fn
+    (clause)
+    (let ((seen {})) (pl-cmp-vars-into! clause seen) (keys seen))))
+
+;; Create a fresh runtime var for each name in the list; return name->var dict.
+(define
+  pl-cmp-make-var-map
+  (fn
+    (var-names)
+    (let
+      ((m {}))
+      (for-each
+        (fn (name) (dict-set! m name (pl-mk-rt-var name)))
+        var-names)
+      m)))
+
+;; Instantiate a parse-AST term using a pre-built var-map.
+;; ("var" "_") always gets a fresh anonymous var.
+(define
+  pl-cmp-build-term
+  (fn
+    (ast var-map)
+    (cond
+      ((pl-var? ast) ast)
+      ((not (list? ast)) ast)
+      ((empty? ast) ast)
+      ((= (first ast) "var")
+        (let
+          ((name (nth ast 1)))
+          (if (= name "_") (pl-mk-rt-var "_") (dict-get var-map name))))
+      ((or (= (first ast) "atom") (= (first ast) "num") (= (first ast) "str"))
+        ast)
+      ((= (first ast) "compound")
+        (list
+          "compound"
+          (nth ast 1)
+          (map (fn (a) (pl-cmp-build-term a var-map)) (nth ast 2))))
+      ((= (first ast) "clause")
+        (list
+          "clause"
+          (pl-cmp-build-term (nth ast 1) var-map)
+          (pl-cmp-build-term (nth ast 2) var-map)))
+      (true ast))))
+
+;; Compile one parse-AST clause to a lambda.
+;; Pre-computes var names at compile time; creates fresh vars per call.
+(define
+  pl-compile-clause
+  (fn
+    (clause)
+    (let
+      ((var-names (pl-cmp-collect-vars clause))
+        (head-ast (nth clause 1))
+        (body-ast (nth clause 2)))
+      (fn
+        (goal trail db cut-box k)
+        (let
+          ((var-map (pl-cmp-make-var-map var-names)))
+          (let
+            ((fresh-head (pl-cmp-build-term head-ast var-map))
+              (fresh-body (pl-cmp-build-term body-ast var-map)))
+            (let
+              ((mark (pl-trail-mark trail)))
+              (if
+                (pl-unify! goal fresh-head trail)
+                (let
+                  ((r (pl-solve! db fresh-body trail cut-box k)))
+                  (if r true (begin (pl-trail-undo-to! trail mark) false)))
+                (begin (pl-trail-undo-to! trail mark) false)))))))))
+
+;; Try a list of compiled clause lambdas — same cut semantics as pl-try-clauses!.
+(define
+  pl-try-compiled-clauses!
+  (fn
+    (db
+      goal
+      trail
+      compiled-clauses
+      outer-cut-box
+      outer-was-cut
+      inner-cut-box
+      k)
+    (cond
+      ((empty? compiled-clauses) false)
+      (true
+        (let
+          ((r ((first compiled-clauses) goal trail db inner-cut-box k)))
+          (cond
+            (r true)
+            ((dict-get inner-cut-box :cut) false)
+            ((and (not outer-was-cut) (dict-get outer-cut-box :cut)) false)
+            (true
+              (pl-try-compiled-clauses!
+                db
+                goal
+                trail
+                (rest compiled-clauses)
+                outer-cut-box
+                outer-was-cut
+                inner-cut-box
+                k))))))))
+
+;; Compile all clauses in DB and store in :compiled table.
+;; After this call, pl-solve-user! will dispatch via compiled lambdas.
+;; Note: clauses assert!-ed after this call are not compiled.
+(define
+  pl-compile-db!
+  (fn
+    (db)
+    (let
+      ((src-table (dict-get db :clauses)) (compiled-table {}))
+      (for-each
+        (fn
+          (key)
+          (dict-set!
+            compiled-table
+            key
+            (map pl-compile-clause (dict-get src-table key))))
+        (keys src-table))
+      (dict-set! db :compiled compiled-table)
+      db)))
+
+;; Cross-validate: load src into both a plain and a compiled DB,
+;; run goal-str through each, return true iff solution counts match.
+;; Use this to keep the interpreter as the reference implementation.
+(define
+  pl-compiled-matches-interp?
+  (fn
+    (src goal-str)
+    (let
+      ((db-interp (pl-mk-db)) (db-comp (pl-mk-db)))
+      (pl-db-load! db-interp (pl-parse src))
+      (pl-db-load! db-comp (pl-parse src))
+      (pl-compile-db! db-comp)
+      (let
+        ((gi (pl-instantiate (pl-parse-goal goal-str) {}))
+          (gc (pl-instantiate (pl-parse-goal goal-str) {})))
+        (=
+          (pl-solve-count! db-interp gi (pl-mk-trail))
+          (pl-solve-count! db-comp gc (pl-mk-trail)))))))

lib/prolog/conformance.sh

@@ -0,0 +1,129 @@
+#!/usr/bin/env bash
+# Run every Prolog test suite via sx_server and refresh scoreboard.{json,md}.
+# Exit 0 if all green, 1 if any failures.
+set -euo pipefail
+
+HERE="$(cd "$(dirname "$0")" && pwd)"
+ROOT="$(cd "$HERE/../.." && pwd)"
+SX="${SX_SERVER:-/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe}"
+
+if [[ ! -x "$SX" ]]; then
+  echo "sx_server not found at $SX (set SX_SERVER env to override)" >&2
+  exit 2
+fi
+
+cd "$ROOT"
+
+# name : test-file : runner-fn
+SUITES=(
+  "parse:lib/prolog/tests/parse.sx:pl-parse-tests-run!"
+  "unify:lib/prolog/tests/unify.sx:pl-unify-tests-run!"
+  "clausedb:lib/prolog/tests/clausedb.sx:pl-clausedb-tests-run!"
+  "solve:lib/prolog/tests/solve.sx:pl-solve-tests-run!"
+  "operators:lib/prolog/tests/operators.sx:pl-operators-tests-run!"
+  "dynamic:lib/prolog/tests/dynamic.sx:pl-dynamic-tests-run!"
+  "findall:lib/prolog/tests/findall.sx:pl-findall-tests-run!"
+  "term_inspect:lib/prolog/tests/term_inspect.sx:pl-term-inspect-tests-run!"
+  "append:lib/prolog/tests/programs/append.sx:pl-append-tests-run!"
+  "reverse:lib/prolog/tests/programs/reverse.sx:pl-reverse-tests-run!"
+  "member:lib/prolog/tests/programs/member.sx:pl-member-tests-run!"
+  "nqueens:lib/prolog/tests/programs/nqueens.sx:pl-nqueens-tests-run!"
+  "family:lib/prolog/tests/programs/family.sx:pl-family-tests-run!"
+  "atoms:lib/prolog/tests/atoms.sx:pl-atom-tests-run!"
+  "query_api:lib/prolog/tests/query_api.sx:pl-query-api-tests-run!"
+  "iso_predicates:lib/prolog/tests/iso_predicates.sx:pl-iso-predicates-tests-run!"
+  "meta_predicates:lib/prolog/tests/meta_predicates.sx:pl-meta-predicates-tests-run!"
+  "list_predicates:lib/prolog/tests/list_predicates.sx:pl-list-predicates-tests-run!"
+  "meta_call:lib/prolog/tests/meta_call.sx:pl-meta-call-tests-run!"
+  "set_predicates:lib/prolog/tests/set_predicates.sx:pl-set-predicates-tests-run!"
+  "char_predicates:lib/prolog/tests/char_predicates.sx:pl-char-predicates-tests-run!"
+  "io_predicates:lib/prolog/tests/io_predicates.sx:pl-io-predicates-tests-run!"
+  "assert_rules:lib/prolog/tests/assert_rules.sx:pl-assert-rules-tests-run!"
+  "string_agg:lib/prolog/tests/string_agg.sx:pl-string-agg-tests-run!"
+  "advanced:lib/prolog/tests/advanced.sx:pl-advanced-tests-run!"
+  "compiler:lib/prolog/tests/compiler.sx:pl-compiler-tests-run!"
+  "cross_validate:lib/prolog/tests/cross_validate.sx:pl-cross-validate-tests-run!"
+  "integration:lib/prolog/tests/integration.sx:pl-integration-tests-run!"
+  "hs_bridge:lib/prolog/tests/hs_bridge.sx:pl-hs-bridge-tests-run!"
+)
+
+SCRIPT='(epoch 1)
+(load "lib/prolog/tokenizer.sx")
+(load "lib/prolog/parser.sx")
+(load "lib/prolog/runtime.sx")
+(load "lib/prolog/query.sx")
+(load "lib/prolog/compiler.sx")
+(load "lib/prolog/hs-bridge.sx")'
+for entry in "${SUITES[@]}"; do
+  IFS=: read -r _ file _ <<< "$entry"
+  SCRIPT+=$'\n(load "'"$file"$'")'
+done
+for entry in "${SUITES[@]}"; do
+  IFS=: read -r _ _ fn <<< "$entry"
+  SCRIPT+=$'\n(eval "('"$fn"$')")'
+done
+
+OUTPUT="$(printf '%s\n' "$SCRIPT" | "$SX" 2>&1)"
+
+mapfile -t LINES < <(printf '%s\n' "$OUTPUT" | grep -E '^\{:failed')
+
+if [[ ${#LINES[@]} -ne ${#SUITES[@]} ]]; then
+  echo "Expected ${#SUITES[@]} suite results, got ${#LINES[@]}" >&2
+  echo "---- raw output ----" >&2
+  printf '%s\n' "$OUTPUT" >&2
+  exit 3
+fi
+
+TOTAL_PASS=0
+TOTAL_FAIL=0
+TOTAL=0
+JSON_SUITES=""
+MD_ROWS=""
+
+for i in "${!SUITES[@]}"; do
+  IFS=: read -r name _ _ <<< "${SUITES[$i]}"
+  line="${LINES[$i]}"
+  passed=$(grep -oE ':passed [0-9]+' <<< "$line" | grep -oE '[0-9]+')
+  total=$(grep -oE ':total [0-9]+' <<< "$line" | grep -oE '[0-9]+')
+  failed=$(grep -oE ':failed [0-9]+' <<< "$line" | grep -oE '[0-9]+')
+  TOTAL_PASS=$((TOTAL_PASS + passed))
+  TOTAL_FAIL=$((TOTAL_FAIL + failed))
+  TOTAL=$((TOTAL + total))
+  status="ok"
+  [[ "$failed" -gt 0 ]] && status="FAIL"
+  [[ -n "$JSON_SUITES" ]] && JSON_SUITES+=","
+  JSON_SUITES+="\"$name\":{\"passed\":$passed,\"total\":$total,\"failed\":$failed}"
+  MD_ROWS+="| $name | $passed | $total | $status |"$'\n'
+done
+
+WHEN="$(date -Iseconds 2>/dev/null || date)"
+
+cat > "$HERE/scoreboard.json" <<JSON
+{
+  "total_passed": $TOTAL_PASS,
+  "total_failed": $TOTAL_FAIL,
+  "total": $TOTAL,
+  "suites": {$JSON_SUITES},
+  "generated": "$WHEN"
+}
+JSON
+
+cat > "$HERE/scoreboard.md" <<MD
+# Prolog scoreboard
+
+**$TOTAL_PASS / $TOTAL passing** ($TOTAL_FAIL failure(s)).
+Generated $WHEN.
+
+| Suite | Passed | Total | Status |
+|-------|--------|-------|--------|
+$MD_ROWS
+Run \`bash lib/prolog/conformance.sh\` to refresh. Override the binary
+with \`SX_SERVER=path/to/sx_server.exe bash …\`.
+MD
+
+if [[ "$TOTAL_FAIL" -gt 0 ]]; then
+  echo "$TOTAL_FAIL failure(s) across $TOTAL tests" >&2
+  exit 1
+fi
+
+echo "All $TOTAL tests pass."

lib/prolog/hs-bridge.sx

@@ -0,0 +1,84 @@
+;; lib/prolog/hs-bridge.sx — Prolog ↔ Hyperscript bridge
+;;
+;; Two complementary integration styles:
+;;
+;; 1. Hook style — for `prolog(db, "goal(args)")` call syntax in Hyperscript:
+;;      (pl-install-hs-hook!)   ;; call once at startup
+;;    Requires lib/hyperscript/runtime.sx (provides hs-set-prolog-hook!)
+;;
+;; 2. Factory style — for named conditions like `when allowed(user, action)`:
+;;      (define allowed (pl-hs-predicate/2 pl-db "allowed"))
+;;    No parser/compiler changes needed: Hyperscript compiles
+;;    `allowed(user, action)` to `(allowed user action)` — a plain SX call.
+;;
+;; Requires tokenizer.sx, parser.sx, runtime.sx, query.sx loaded first.
+
+;; --- Hook style ---
+
+(define
+  pl-install-hs-hook!
+  (fn
+    ()
+    (hs-set-prolog-hook!
+      (fn (db goal) (not (= nil (pl-query-one db goal)))))))
+
+;; --- Factory style ---
+
+;; Test whether a ground Prolog goal succeeds against db.
+;; Returns true/false (not a solution dict).
+(define
+  pl-hs-query
+  (fn (db goal-str) (not (nil? (pl-query-one db goal-str)))))
+
+;; Build a Prolog goal string from a predicate name and arg list.
+;; SX values: strings/keywords pass through; numbers are stringified via str.
+(define
+  pl-hs-build-goal
+  (fn
+    (pred-name args)
+    (str pred-name "(" (join ", " (map (fn (a) (str a)) args)) ")")))
+
+;; Return a 1-arg SX function that succeeds iff pred(a) holds in db.
+(define
+  pl-hs-predicate/1
+  (fn
+    (db pred-name)
+    (fn (a) (pl-hs-query db (pl-hs-build-goal pred-name (list a))))))
+
+;; Return a 2-arg SX function that succeeds iff pred(a, b) holds in db.
+(define
+  pl-hs-predicate/2
+  (fn
+    (db pred-name)
+    (fn (a b) (pl-hs-query db (pl-hs-build-goal pred-name (list a b))))))
+
+;; Return a 3-arg SX function that succeeds iff pred(a, b, c) holds in db.
+(define
+  pl-hs-predicate/3
+  (fn
+    (db pred-name)
+    (fn (a b c) (pl-hs-query db (pl-hs-build-goal pred-name (list a b c))))))
+
+;; Install every predicate in install-list as a named SX function backed by db.
+;; install-list: list of (name arity) pairs.
+;; Returns a dict {name → fn} for the caller to destructure.
+(define
+  pl-hs-install
+  (fn
+    (db install-list)
+    (reduce
+      (fn
+        (acc entry)
+        (let
+          ((pred-name (first entry)) (arity (nth entry 1)))
+          (dict-set!
+            acc
+            pred-name
+            (cond
+              ((= arity 1) (pl-hs-predicate/1 db pred-name))
+              ((= arity 2) (pl-hs-predicate/2 db pred-name))
+              ((= arity 3) (pl-hs-predicate/3 db pred-name))
+              (true (fn (a b) false))))
+          acc))
+      {}
+      install-list)))

lib/prolog/parser.sx

@@ -1,28 +1,20 @@
 ;; lib/prolog/parser.sx — tokens → Prolog AST
 ;;
-;; Phase 1 grammar (NO operator table yet):
+;; Phase 4 grammar (with operator table):
 ;;   Program      := Clause* EOF
-;;   Clause       := Term "." | Term ":-" Term "."
-;;   Term         := Atom | Var | Number | String | Compound | List
-;;   Compound     := atom "(" ArgList ")"
-;;   ArgList      := Term ("," Term)*
-;;   List         := "[" "]" | "[" Term ("," Term)* ("|" Term)? "]"
+;;   Clause       := Term[999] "." | Term[999] ":-" Term[1200] "."
+;;   Term[Pmax] uses precedence climbing on the operator table:
+;;     primary = Atom | Var | Number | String | Compound | List | "(" Term[1200] ")"
+;;     while next token is infix op `op` with prec(op) ≤ Pmax:
+;;       consume op; parse rhs at right-prec(op); fold into compound(op-name,[lhs,rhs])
 ;;
-;; Term AST shapes (all tagged lists for uniform dispatch):
-;;   ("atom"  name)            — atom
-;;   ("var"   name)            — variable template (parser-time only)
-;;   ("num"   value)           — integer or float
-;;   ("str"   value)           — string literal
-;;   ("compound" functor args) — compound term, args is list of term-ASTs
-;;   ("cut")                   — the cut atom !
+;; Op type → right-prec for op at precedence P:
+;;   xfx → P-1   strict-both
+;;   xfy → P     right-associative
+;;   yfx → P-1   left-associative
 ;;
-;; A clause is (list "clause" head body). A fact is head with body = ("atom" "true").
-;;
-;; The empty list is (atom "[]"). Cons is compound "." with two args:
-;; [1, 2, 3]   → .(1, .(2, .(3, [])))
-;; [H|T]       → .(H, T)
+;; AST shapes are unchanged — operators just become compound terms.
 
-;; ── Parser state helpers ────────────────────────────────────────────
 (define
   pp-peek
   (fn
@@ -66,7 +58,6 @@
             (if (= (get t :value) nil) "" (get t :value))
             "'"))))))
 
-;; ── AST constructors ────────────────────────────────────────────────
 (define pl-mk-atom (fn (name) (list "atom" name)))
 (define pl-mk-var (fn (name) (list "var" name)))
 (define pl-mk-num (fn (n) (list "num" n)))
@@ -74,18 +65,14 @@
 (define pl-mk-compound (fn (f args) (list "compound" f args)))
 (define pl-mk-cut (fn () (list "cut")))
 
-;; Term tag extractors
 (define pl-term-tag (fn (t) (if (list? t) (first t) nil)))
 (define pl-term-val (fn (t) (nth t 1)))
 (define pl-compound-functor (fn (t) (nth t 1)))
 (define pl-compound-args (fn (t) (nth t 2)))
 
-;; Empty-list atom and cons helpers
 (define pl-nil-term (fn () (pl-mk-atom "[]")))
-
 (define pl-mk-cons (fn (h t) (pl-mk-compound "." (list h t))))
 
-;; Build cons list from a list of terms + optional tail
 (define
   pl-mk-list-term
   (fn
@@ -95,9 +82,61 @@
       tail
       (pl-mk-cons (first items) (pl-mk-list-term (rest items) tail)))))
 
-;; ── Term parser ─────────────────────────────────────────────────────
+;; ── Operator table (Phase 4) ──────────────────────────────────────
+;; Each entry: (name precedence type). Type ∈ "xfx" "xfy" "yfx".
 (define
-  pp-parse-term
+  pl-op-table
+  (list
+    (list "," 1000 "xfy")
+    (list ";" 1100 "xfy")
+    (list "->" 1050 "xfy")
+    (list "=" 700 "xfx")
+    (list "\\=" 700 "xfx")
+    (list "is" 700 "xfx")
+    (list "<" 700 "xfx")
+    (list ">" 700 "xfx")
+    (list "=<" 700 "xfx")
+    (list ">=" 700 "xfx")
+    (list "+" 500 "yfx")
+    (list "-" 500 "yfx")
+    (list "*" 400 "yfx")
+    (list "/" 400 "yfx")
+    (list ":-" 1200 "xfx")
+    (list "mod" 400 "yfx")))
+
+(define
+  pl-op-find
+  (fn
+    (name table)
+    (cond
+      ((empty? table) nil)
+      ((= (first (first table)) name) (rest (first table)))
+      (true (pl-op-find name (rest table))))))
+
+(define pl-op-lookup (fn (name) (pl-op-find name pl-op-table)))
+
+;; Token → (name prec type) for known infix ops, else nil.
+(define
+  pl-token-op
+  (fn
+    (t)
+    (let
+      ((ty (get t :type)) (vv (get t :value)))
+      (cond
+        ((and (= ty "punct") (= vv ","))
+          (let
+            ((info (pl-op-lookup ",")))
+            (if (nil? info) nil (cons "," info))))
+        ((or (= ty "atom") (= ty "op"))
+          (let
+            ((info (pl-op-lookup vv)))
+            (if (nil? info) nil (cons vv info))))
+        (true nil)))))
+
+;; ── Term parser ─────────────────────────────────────────────────────
+;; Primary term: atom, var, num, str, compound (atom + paren), list, cut, parens.
+(define
+  pp-parse-primary
   (fn
     (st)
     (let
@@ -111,6 +150,12 @@
           ((and (= ty "op") (= vv "!"))
             (do (pp-advance! st) (pl-mk-cut)))
           ((and (= ty "punct") (= vv "[")) (pp-parse-list st))
+          ((and (= ty "punct") (= vv "("))
+            (do
+              (pp-advance! st)
+              (let
+                ((inner (pp-parse-term-prec st 1200)))
+                (do (pp-expect! st "punct" ")") inner))))
           ((= ty "atom")
             (do
               (pp-advance! st)
@@ -133,13 +178,51 @@
                 (if (= vv nil) "" vv)
                 "'"))))))))
 
-;; Parse one or more comma-separated terms (arguments).
+;; Operator-aware term parser: precedence climbing.
+(define
+  pp-parse-term-prec
+  (fn
+    (st max-prec)
+    (let ((left (pp-parse-primary st))) (pp-parse-op-rhs st left max-prec))))
+
+(define
+  pp-parse-op-rhs
+  (fn
+    (st left max-prec)
+    (let
+      ((op-info (pl-token-op (pp-peek st))))
+      (cond
+        ((nil? op-info) left)
+        (true
+          (let
+            ((name (first op-info))
+              (prec (nth op-info 1))
+              (ty (nth op-info 2)))
+            (cond
+              ((> prec max-prec) left)
+              (true
+                (let
+                  ((right-prec (if (= ty "xfy") prec (- prec 1))))
+                  (do
+                    (pp-advance! st)
+                    (let
+                      ((right (pp-parse-term-prec st right-prec)))
+                      (pp-parse-op-rhs
+                        st
+                        (pl-mk-compound name (list left right))
+                        max-prec))))))))))))
+
+;; Backwards-compat alias.
+(define pp-parse-term (fn (st) (pp-parse-term-prec st 999)))
+
+;; Args inside parens: parse at prec 999 so comma-as-operator (1000)
+;; is not consumed; the explicit comma loop handles separation.
 (define
   pp-parse-arg-list
   (fn
     (st)
     (let
-      ((first-arg (pp-parse-term st)) (args (list)))
+      ((first-arg (pp-parse-term-prec st 999)) (args (list)))
       (do
         (append! args first-arg)
         (define
@@ -150,12 +233,12 @@
               (pp-at? st "punct" ",")
               (do
                 (pp-advance! st)
-                (append! args (pp-parse-term st))
+                (append! args (pp-parse-term-prec st 999))
                 (loop)))))
         (loop)
         args))))
 
-;; Parse a [ ... ] list literal. Consumes the "[".
+;; List literal.
 (define
   pp-parse-list
   (fn
@@ -168,7 +251,7 @@
         (let
           ((items (list)))
           (do
-            (append! items (pp-parse-term st))
+            (append! items (pp-parse-term-prec st 999))
             (define
               comma-loop
               (fn
@@ -177,52 +260,17 @@
                   (pp-at? st "punct" ",")
                   (do
                     (pp-advance! st)
-                    (append! items (pp-parse-term st))
+                    (append! items (pp-parse-term-prec st 999))
                     (comma-loop)))))
             (comma-loop)
             (let
-              ((tail (if (pp-at? st "punct" "|") (do (pp-advance! st) (pp-parse-term st)) (pl-nil-term))))
+              ((tail (if (pp-at? st "punct" "|") (do (pp-advance! st) (pp-parse-term-prec st 999)) (pl-nil-term))))
               (do (pp-expect! st "punct" "]") (pl-mk-list-term items tail)))))))))
 
 ;; ── Body parsing ────────────────────────────────────────────────────
-;; A clause body is a comma-separated list of goals. We flatten into a
-;; right-associative `,` compound: (A, B, C) → ','(A, ','(B, C))
-;; If only one goal, it's that goal directly.
-(define
-  pp-parse-body
-  (fn
-    (st)
-    (let
-      ((first-goal (pp-parse-term st)) (rest-goals (list)))
-      (do
-        (define
-          gloop
-          (fn
-            ()
-            (when
-              (pp-at? st "punct" ",")
-              (do
-                (pp-advance! st)
-                (append! rest-goals (pp-parse-term st))
-                (gloop)))))
-        (gloop)
-        (if
-          (= (len rest-goals) 0)
-          first-goal
-          (pp-build-conj first-goal rest-goals))))))
-
-(define
-  pp-build-conj
-  (fn
-    (first-goal rest-goals)
-    (if
-      (= (len rest-goals) 0)
-      first-goal
-      (pl-mk-compound
-        ","
-        (list
-          first-goal
-          (pp-build-conj (first rest-goals) (rest rest-goals)))))))
+;; A body is a single term parsed at prec 1200 — operator parser folds
+;; `,`, `;`, `->` automatically into right-associative compounds.
+(define pp-parse-body (fn (st) (pp-parse-term-prec st 1200)))
 
 ;; ── Clause parsing ──────────────────────────────────────────────────
 (define
@@ -230,12 +278,11 @@
   (fn
     (st)
     (let
-      ((head (pp-parse-term st)))
+      ((head (pp-parse-term-prec st 999)))
       (let
         ((body (if (pp-at? st "op" ":-") (do (pp-advance! st) (pp-parse-body st)) (pl-mk-atom "true"))))
         (do (pp-expect! st "punct" ".") (list "clause" head body))))))
 
-;; Parse an entire program — returns list of clauses.
 (define
   pl-parse-program
   (fn
@@ -253,13 +300,9 @@
         (ploop)
         clauses))))
 
-;; Parse a single query term (no trailing "."). Returns the term.
 (define
   pl-parse-query
   (fn (tokens) (let ((st {:idx 0 :tokens tokens})) (pp-parse-body st))))
 
-;; Convenience: source → clauses
 (define pl-parse (fn (src) (pl-parse-program (pl-tokenize src))))
-
-;; Convenience: source → query term
 (define pl-parse-goal (fn (src) (pl-parse-query (pl-tokenize src))))

lib/prolog/query.sx

@@ -0,0 +1,114 @@
+;; lib/prolog/query.sx — high-level Prolog query API for SX/Hyperscript callers.
+;;
+;; Requires tokenizer.sx, parser.sx, runtime.sx to be loaded first.
+;;
+;; Public API:
+;;   (pl-load source-str)                → db
+;;   (pl-query-all db query-str)         → list of solution dicts {var-name → term-string}
+;;   (pl-query-one db query-str)         → first solution dict or nil
+;;   (pl-query source-str query-str)     → list of solution dicts (convenience)
+
+;; Collect variable name strings from a parse-time AST (pre-instantiation).
+;; Returns list of unique strings, excluding anonymous "_".
+(define
+  pl-query-extract-vars
+  (fn
+    (ast)
+    (let
+      ((seen {}))
+      (let
+        ((collect!
+          (fn
+            (t)
+            (cond
+              ((not (list? t)) nil)
+              ((empty? t) nil)
+              ((= (first t) "var")
+                (if
+                  (not (= (nth t 1) "_"))
+                  (dict-set! seen (nth t 1) true)
+                  nil))
+              ((= (first t) "compound")
+                (for-each collect! (nth t 2)))
+              (true nil)))))
+        (collect! ast)
+        (keys seen)))))
+
+;; Build a solution dict from a var-env after a successful solve.
+;; Maps each variable name string to its formatted term value.
+(define
+  pl-query-solution-dict
+  (fn
+    (var-names var-env)
+    (let
+      ((d {}))
+      (for-each
+        (fn (name) (dict-set! d name (pl-format-term (dict-get var-env name))))
+        var-names)
+      d)))
+
+;; Parse source-str and load clauses into a fresh DB.
+;; Returns the DB for reuse across multiple queries.
+(define
+  pl-load
+  (fn
+    (source-str)
+    (let
+      ((db (pl-mk-db)))
+      (if
+        (and (string? source-str) (not (= source-str "")))
+        (pl-db-load! db (pl-parse source-str))
+        nil)
+      db)))
+
+;; Run query-str against db, returning a list of solution dicts.
+;; Each dict maps variable name strings to their formatted term values.
+;; Returns an empty list if no solutions.
+(define
+  pl-query-all
+  (fn
+    (db query-str)
+    (let
+      ((parsed (pl-parse (str "q_ :- " query-str "."))))
+      (let
+        ((body-ast (nth (first parsed) 2)))
+        (let
+          ((var-names (pl-query-extract-vars body-ast))
+           (var-env {}))
+          (let
+            ((goal (pl-instantiate body-ast var-env))
+             (trail (pl-mk-trail))
+             (solutions (list)))
+            (let
+              ((mark (pl-trail-mark trail)))
+              (pl-solve!
+                db
+                goal
+                trail
+                {:cut false}
+                (fn
+                  ()
+                  (begin
+                    (append!
+                      solutions
+                      (pl-query-solution-dict var-names var-env))
+                    false)))
+              (pl-trail-undo-to! trail mark)
+              solutions)))))))
+
+;; Return the first solution dict, or nil if no solutions.
+(define
+  pl-query-one
+  (fn
+    (db query-str)
+    (let
+      ((all (pl-query-all db query-str)))
+      (if (empty? all) nil (first all)))))
+
+;; Convenience: parse source-str, then run query-str against it.
+;; Returns a list of solution dicts. Creates a fresh DB each call.
+(define
+  pl-query
+  (fn
+    (source-str query-str)
+    (pl-query-all (pl-load source-str) query-str)))

lib/prolog/scoreboard.json

@@ -0,0 +1,7 @@
+{
+  "total_passed": 590,
+  "total_failed": 0,
+  "total": 590,
+  "suites": {"parse":{"passed":25,"total":25,"failed":0},"unify":{"passed":47,"total":47,"failed":0},"clausedb":{"passed":14,"total":14,"failed":0},"solve":{"passed":62,"total":62,"failed":0},"operators":{"passed":19,"total":19,"failed":0},"dynamic":{"passed":11,"total":11,"failed":0},"findall":{"passed":11,"total":11,"failed":0},"term_inspect":{"passed":14,"total":14,"failed":0},"append":{"passed":6,"total":6,"failed":0},"reverse":{"passed":6,"total":6,"failed":0},"member":{"passed":7,"total":7,"failed":0},"nqueens":{"passed":6,"total":6,"failed":0},"family":{"passed":10,"total":10,"failed":0},"atoms":{"passed":34,"total":34,"failed":0},"query_api":{"passed":16,"total":16,"failed":0},"iso_predicates":{"passed":29,"total":29,"failed":0},"meta_predicates":{"passed":25,"total":25,"failed":0},"list_predicates":{"passed":33,"total":33,"failed":0},"meta_call":{"passed":15,"total":15,"failed":0},"set_predicates":{"passed":15,"total":15,"failed":0},"char_predicates":{"passed":27,"total":27,"failed":0},"io_predicates":{"passed":24,"total":24,"failed":0},"assert_rules":{"passed":15,"total":15,"failed":0},"string_agg":{"passed":25,"total":25,"failed":0},"advanced":{"passed":21,"total":21,"failed":0},"compiler":{"passed":17,"total":17,"failed":0},"cross_validate":{"passed":17,"total":17,"failed":0},"integration":{"passed":20,"total":20,"failed":0},"hs_bridge":{"passed":19,"total":19,"failed":0}},
+  "generated": "2026-05-06T12:17:46+00:00"
+}

lib/prolog/scoreboard.md

@@ -0,0 +1,39 @@
+# Prolog scoreboard
+
+**590 / 590 passing** (0 failure(s)).
+Generated 2026-05-06T12:17:46+00:00.
+
+| Suite | Passed | Total | Status |
+|-------|--------|-------|--------|
+| parse | 25 | 25 | ok |
+| unify | 47 | 47 | ok |
+| clausedb | 14 | 14 | ok |
+| solve | 62 | 62 | ok |
+| operators | 19 | 19 | ok |
+| dynamic | 11 | 11 | ok |
+| findall | 11 | 11 | ok |
+| term_inspect | 14 | 14 | ok |
+| append | 6 | 6 | ok |
+| reverse | 6 | 6 | ok |
+| member | 7 | 7 | ok |
+| nqueens | 6 | 6 | ok |
+| family | 10 | 10 | ok |
+| atoms | 34 | 34 | ok |
+| query_api | 16 | 16 | ok |
+| iso_predicates | 29 | 29 | ok |
+| meta_predicates | 25 | 25 | ok |
+| list_predicates | 33 | 33 | ok |
+| meta_call | 15 | 15 | ok |
+| set_predicates | 15 | 15 | ok |
+| char_predicates | 27 | 27 | ok |
+| io_predicates | 24 | 24 | ok |
+| assert_rules | 15 | 15 | ok |
+| string_agg | 25 | 25 | ok |
+| advanced | 21 | 21 | ok |
+| compiler | 17 | 17 | ok |
+| cross_validate | 17 | 17 | ok |
+| integration | 20 | 20 | ok |
+| hs_bridge | 19 | 19 | ok |
+
+Run `bash lib/prolog/conformance.sh` to refresh. Override the binary
+with `SX_SERVER=path/to/sx_server.exe bash …`.

lib/prolog/tests/advanced.sx

@@ -0,0 +1,254 @@
+;; lib/prolog/tests/advanced.sx — predsort/3, term_variables/2, arith extensions
+
+(define pl-adv-test-count 0)
+(define pl-adv-test-pass 0)
+(define pl-adv-test-fail 0)
+(define pl-adv-test-failures (list))
+
+(define
+  pl-adv-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-adv-test-count (+ pl-adv-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-adv-test-pass (+ pl-adv-test-pass 1))
+        (begin
+          (set! pl-adv-test-fail (+ pl-adv-test-fail 1))
+          (append!
+            pl-adv-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-adv-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-adv-db (pl-mk-db))
+;; Load a numeric comparator for predsort tests
+(pl-db-load!
+  pl-adv-db
+  (pl-parse
+    "cmp_num(Order, X, Y) :- (X < Y -> Order = '<' ; (X > Y -> Order = '>' ; Order = '='))."))
+
+;; ── Arithmetic extensions ──────────────────────────────────────────
+
+(define pl-adv-arith-env-1 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is floor(3.7)" pl-adv-arith-env-1)
+  (pl-mk-trail))
+(pl-adv-test!
+  "floor(3.7) = 3"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-1 "X")))
+  3)
+
+(define pl-adv-arith-env-2 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is ceiling(3.2)" pl-adv-arith-env-2)
+  (pl-mk-trail))
+(pl-adv-test!
+  "ceiling(3.2) = 4"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-2 "X")))
+  4)
+
+(define pl-adv-arith-env-3 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is truncate(3.9)" pl-adv-arith-env-3)
+  (pl-mk-trail))
+(pl-adv-test!
+  "truncate(3.9) = 3"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-3 "X")))
+  3)
+
+(define pl-adv-arith-env-4 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is truncate(0 - 3.9)" pl-adv-arith-env-4)
+  (pl-mk-trail))
+(pl-adv-test!
+  "truncate(0-3.9) = -3"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-4 "X")))
+  -3)
+
+(define pl-adv-arith-env-5 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is round(3.5)" pl-adv-arith-env-5)
+  (pl-mk-trail))
+(pl-adv-test!
+  "round(3.5) = 4"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-5 "X")))
+  4)
+
+(define pl-adv-arith-env-6 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is sqrt(4.0)" pl-adv-arith-env-6)
+  (pl-mk-trail))
+(pl-adv-test!
+  "sqrt(4.0) = 2"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-6 "X")))
+  2)
+
+(define pl-adv-arith-env-7 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is sign(0 - 5)" pl-adv-arith-env-7)
+  (pl-mk-trail))
+(pl-adv-test!
+  "sign(0-5) = -1"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-7 "X")))
+  -1)
+
+(define pl-adv-arith-env-8 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is sign(0)" pl-adv-arith-env-8)
+  (pl-mk-trail))
+(pl-adv-test!
+  "sign(0) = 0"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-8 "X")))
+  0)
+
+(define pl-adv-arith-env-9 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is sign(3)" pl-adv-arith-env-9)
+  (pl-mk-trail))
+(pl-adv-test!
+  "sign(3) = 1"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-9 "X")))
+  1)
+
+(define pl-adv-arith-env-10 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is pow(2, 3)" pl-adv-arith-env-10)
+  (pl-mk-trail))
+(pl-adv-test!
+  "pow(2,3) = 8"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-10 "X")))
+  8)
+
+(define pl-adv-arith-env-11 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is floor(0 - 3.7)" pl-adv-arith-env-11)
+  (pl-mk-trail))
+(pl-adv-test!
+  "floor(0-3.7) = -4"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-11 "X")))
+  -4)
+
+(define pl-adv-arith-env-12 {:X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "X is ceiling(0 - 3.2)" pl-adv-arith-env-12)
+  (pl-mk-trail))
+(pl-adv-test!
+  "ceiling(0-3.2) = -3"
+  (pl-num-val (pl-walk-deep (dict-get pl-adv-arith-env-12 "X")))
+  -3)
+
+;; ── term_variables/2 ──────────────────────────────────────────────
+
+(define pl-adv-tv-env-1 {:Vs (pl-mk-rt-var "Vs")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "term_variables(hello, Vs)" pl-adv-tv-env-1)
+  (pl-mk-trail))
+(pl-adv-test!
+  "term_variables(hello,Vs) -> []"
+  (pl-format-term (pl-walk-deep (dict-get pl-adv-tv-env-1 "Vs")))
+  "[]")
+
+(define pl-adv-tv-env-2 {:Vs (pl-mk-rt-var "Vs")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "term_variables(f(a, g(b)), Vs)" pl-adv-tv-env-2)
+  (pl-mk-trail))
+(pl-adv-test!
+  "term_variables(f(a,g(b)),Vs) -> []"
+  (pl-format-term (pl-walk-deep (dict-get pl-adv-tv-env-2 "Vs")))
+  "[]")
+
+(define pl-adv-tv-env-3 {:Y (pl-mk-rt-var "Y") :Vs (pl-mk-rt-var "Vs") :X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "term_variables(f(X, Y), Vs)" pl-adv-tv-env-3)
+  (pl-mk-trail))
+(pl-adv-test!
+  "term_variables(f(X,Y),Vs) has 2 vars"
+  (pl-list-length (pl-walk-deep (dict-get pl-adv-tv-env-3 "Vs")))
+  2)
+
+(define pl-adv-tv-env-4 {:Vs (pl-mk-rt-var "Vs") :X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "term_variables(X, Vs)" pl-adv-tv-env-4)
+  (pl-mk-trail))
+(pl-adv-test!
+  "term_variables(X,Vs) has 1 var"
+  (pl-list-length (pl-walk-deep (dict-get pl-adv-tv-env-4 "Vs")))
+  1)
+
+(define pl-adv-tv-env-5 {:Y (pl-mk-rt-var "Y") :Vs (pl-mk-rt-var "Vs") :X (pl-mk-rt-var "X")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "term_variables(foo(X, Y, X), Vs)" pl-adv-tv-env-5)
+  (pl-mk-trail))
+(pl-adv-test!
+  "term_variables(foo(X,Y,X),Vs) deduplicates X -> 2 vars"
+  (pl-list-length (pl-walk-deep (dict-get pl-adv-tv-env-5 "Vs")))
+  2)
+
+;; ── predsort/3 ────────────────────────────────────────────────────
+
+(define pl-adv-ps-env-1 {:R (pl-mk-rt-var "R")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "predsort(cmp_num, [], R)" pl-adv-ps-env-1)
+  (pl-mk-trail))
+(pl-adv-test!
+  "predsort([]) -> []"
+  (pl-format-term (pl-walk-deep (dict-get pl-adv-ps-env-1 "R")))
+  "[]")
+
+(define pl-adv-ps-env-2 {:R (pl-mk-rt-var "R")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "predsort(cmp_num, [1], R)" pl-adv-ps-env-2)
+  (pl-mk-trail))
+(pl-adv-test!
+  "predsort([1]) -> [1]"
+  (pl-format-term (pl-walk-deep (dict-get pl-adv-ps-env-2 "R")))
+  ".(1, [])")
+
+(define pl-adv-ps-env-3 {:R (pl-mk-rt-var "R")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "predsort(cmp_num, [3,1,2], R)" pl-adv-ps-env-3)
+  (pl-mk-trail))
+(pl-adv-test!
+  "predsort([3,1,2]) -> [1,2,3]"
+  (pl-format-term (pl-walk-deep (dict-get pl-adv-ps-env-3 "R")))
+  ".(1, .(2, .(3, [])))")
+
+(define pl-adv-ps-env-4 {:R (pl-mk-rt-var "R")})
+(pl-solve-once!
+  pl-adv-db
+  (pl-adv-goal "predsort(cmp_num, [3,1,2,1,3], R)" pl-adv-ps-env-4)
+  (pl-mk-trail))
+(pl-adv-test!
+  "predsort([3,1,2,1,3]) dedup -> [1,2,3]"
+  (pl-format-term (pl-walk-deep (dict-get pl-adv-ps-env-4 "R")))
+  ".(1, .(2, .(3, [])))")
+
+;; ── Runner ─────────────────────────────────────────────────────────
+
+(define pl-advanced-tests-run! (fn () {:failed pl-adv-test-fail :passed pl-adv-test-pass :total pl-adv-test-count :failures pl-adv-test-failures}))

lib/prolog/tests/assert_rules.sx

@@ -0,0 +1,215 @@
+;; lib/prolog/tests/assert_rules.sx — assert/assertz/asserta with rule terms (head :- body)
+;; Tests that :- is in the op table (prec 1200 xfx) and pl-build-clause handles rule form.
+
+(define pl-ar-test-count 0)
+(define pl-ar-test-pass 0)
+(define pl-ar-test-fail 0)
+(define pl-ar-test-failures (list))
+
+(define
+  pl-ar-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-ar-test-count (+ pl-ar-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-ar-test-pass (+ pl-ar-test-pass 1))
+        (begin
+          (set! pl-ar-test-fail (+ pl-ar-test-fail 1))
+          (append!
+            pl-ar-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-ar-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+;; ── DB1: assertz a simple rule then query ──────────────────────────
+(define pl-ar-db1 (pl-mk-db))
+
+(pl-solve-once!
+  pl-ar-db1
+  (pl-ar-goal "assertz((double(X, Y) :- Y is X * 2))" {})
+  (pl-mk-trail))
+
+(pl-ar-test!
+  "assertz rule: double(3, Y) succeeds"
+  (pl-solve-once!
+    pl-ar-db1
+    (pl-ar-goal "double(3, Y)" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-ar-env1 {})
+(pl-solve-once!
+  pl-ar-db1
+  (pl-ar-goal "double(3, Y)" pl-ar-env1)
+  (pl-mk-trail))
+
+(pl-ar-test!
+  "assertz rule: double(3, Y) binds Y to 6"
+  (pl-num-val (pl-walk-deep (dict-get pl-ar-env1 "Y")))
+  6)
+
+(define pl-ar-env1b {})
+(pl-solve-once!
+  pl-ar-db1
+  (pl-ar-goal "double(10, Y)" pl-ar-env1b)
+  (pl-mk-trail))
+
+(pl-ar-test!
+  "assertz rule: double(10, Y) yields 20"
+  (pl-num-val (pl-walk-deep (dict-get pl-ar-env1b "Y")))
+  20)
+
+;; ── DB2: assert a rule with multiple facts, count solutions ─────────
+(define pl-ar-db2 (pl-mk-db))
+
+(pl-solve-once!
+  pl-ar-db2
+  (pl-ar-goal "assert(fact(a))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-ar-db2
+  (pl-ar-goal "assert(fact(b))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-ar-db2
+  (pl-ar-goal "assertz((copy(X) :- fact(X)))" {})
+  (pl-mk-trail))
+
+(pl-ar-test!
+  "rule copy/1 using fact/1: 2 solutions"
+  (pl-solve-count! pl-ar-db2 (pl-ar-goal "copy(X)" {}) (pl-mk-trail))
+  2)
+
+(define pl-ar-env2a {})
+(pl-solve-once! pl-ar-db2 (pl-ar-goal "copy(X)" pl-ar-env2a) (pl-mk-trail))
+
+(pl-ar-test!
+  "rule copy/1: first solution is a"
+  (pl-atom-name (pl-walk-deep (dict-get pl-ar-env2a "X")))
+  "a")
+
+;; ── DB3: asserta rule is tried before existing clauses ─────────────
+(define pl-ar-db3 (pl-mk-db))
+
+(pl-solve-once!
+  pl-ar-db3
+  (pl-ar-goal "assert(ord(a))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-ar-db3
+  (pl-ar-goal "asserta((ord(b) :- true))" {})
+  (pl-mk-trail))
+
+(define pl-ar-env3 {})
+(pl-solve-once! pl-ar-db3 (pl-ar-goal "ord(X)" pl-ar-env3) (pl-mk-trail))
+
+(pl-ar-test!
+  "asserta rule ord(b) is tried before ord(a)"
+  (pl-atom-name (pl-walk-deep (dict-get pl-ar-env3 "X")))
+  "b")
+
+(pl-ar-test!
+  "asserta: total solutions for ord/1 is 2"
+  (pl-solve-count! pl-ar-db3 (pl-ar-goal "ord(X)" {}) (pl-mk-trail))
+  2)
+
+;; ── DB4: rule with conjunction in body ─────────────────────────────
+(define pl-ar-db4 (pl-mk-db))
+
+(pl-solve-once!
+  pl-ar-db4
+  (pl-ar-goal "assert(num(1))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-ar-db4
+  (pl-ar-goal "assert(num(2))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-ar-db4
+  (pl-ar-goal "assertz((big(X) :- num(X), X > 1))" {})
+  (pl-mk-trail))
+
+(pl-ar-test!
+  "conjunction in rule body: big(1) fails"
+  (pl-solve-once! pl-ar-db4 (pl-ar-goal "big(1)" {}) (pl-mk-trail))
+  false)
+
+(pl-ar-test!
+  "conjunction in rule body: big(2) succeeds"
+  (pl-solve-once! pl-ar-db4 (pl-ar-goal "big(2)" {}) (pl-mk-trail))
+  true)
+
+;; ── DB5: recursive rule ─────────────────────────────────────────────
+(define pl-ar-db5 (pl-mk-db))
+
+(pl-solve-once!
+  pl-ar-db5
+  (pl-ar-goal "assert((nat(0) :- true))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-ar-db5
+  (pl-ar-goal "assertz((nat(s(X)) :- nat(X)))" {})
+  (pl-mk-trail))
+
+(pl-ar-test!
+  "recursive rule: nat(0) succeeds"
+  (pl-solve-once! pl-ar-db5 (pl-ar-goal "nat(0)" {}) (pl-mk-trail))
+  true)
+
+(pl-ar-test!
+  "recursive rule: nat(s(0)) succeeds"
+  (pl-solve-once!
+    pl-ar-db5
+    (pl-ar-goal "nat(s(0))" {})
+    (pl-mk-trail))
+  true)
+
+(pl-ar-test!
+  "recursive rule: nat(s(s(0))) succeeds"
+  (pl-solve-once!
+    pl-ar-db5
+    (pl-ar-goal "nat(s(s(0)))" {})
+    (pl-mk-trail))
+  true)
+
+(pl-ar-test!
+  "recursive rule: nat(bad) fails"
+  (pl-solve-once! pl-ar-db5 (pl-ar-goal "nat(bad)" {}) (pl-mk-trail))
+  false)
+
+;; ── DB6: rule with true body (explicit) ────────────────────────────
+(define pl-ar-db6 (pl-mk-db))
+
+(pl-solve-once!
+  pl-ar-db6
+  (pl-ar-goal "assertz((always(X) :- true))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-ar-db6
+  (pl-ar-goal "assert(always(extra))" {})
+  (pl-mk-trail))
+
+(pl-ar-test!
+  "rule body=true: always(foo) succeeds"
+  (pl-solve-once!
+    pl-ar-db6
+    (pl-ar-goal "always(foo)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-ar-test!
+  "rule body=true: always/1 has 2 clauses (1 rule + 1 fact)"
+  (pl-solve-count!
+    pl-ar-db6
+    (pl-ar-goal "always(X)" {})
+    (pl-mk-trail))
+  2)
+
+;; ── Runner ──────────────────────────────────────────────────────────
+(define pl-assert-rules-tests-run! (fn () {:failed pl-ar-test-fail :passed pl-ar-test-pass :total pl-ar-test-count :failures pl-ar-test-failures}))

lib/prolog/tests/atoms.sx

@@ -0,0 +1,305 @@
+;; lib/prolog/tests/atoms.sx — type predicates + string/atom built-ins
+
+(define pl-at-test-count 0)
+(define pl-at-test-pass 0)
+(define pl-at-test-fail 0)
+(define pl-at-test-failures (list))
+
+(define
+  pl-at-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-at-test-count (+ pl-at-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-at-test-pass (+ pl-at-test-pass 1))
+        (begin
+          (set! pl-at-test-fail (+ pl-at-test-fail 1))
+          (append!
+            pl-at-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-at-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-at-db (pl-mk-db))
+
+;; ── var/1 + nonvar/1 ──
+
+(pl-at-test!
+  "var(X) for unbound var"
+  (pl-solve-once! pl-at-db (pl-at-goal "var(X)" {}) (pl-mk-trail))
+  true)
+(pl-at-test!
+  "var(foo) fails"
+  (pl-solve-once! pl-at-db (pl-at-goal "var(foo)" {}) (pl-mk-trail))
+  false)
+(pl-at-test!
+  "nonvar(foo) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "nonvar(foo)" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "nonvar(X) for unbound var fails"
+  (pl-solve-once! pl-at-db (pl-at-goal "nonvar(X)" {}) (pl-mk-trail))
+  false)
+
+;; ── atom/1 ──
+
+(pl-at-test!
+  "atom(foo) succeeds"
+  (pl-solve-once! pl-at-db (pl-at-goal "atom(foo)" {}) (pl-mk-trail))
+  true)
+(pl-at-test!
+  "atom([]) succeeds"
+  (pl-solve-once! pl-at-db (pl-at-goal "atom([])" {}) (pl-mk-trail))
+  true)
+(pl-at-test!
+  "atom(42) fails"
+  (pl-solve-once! pl-at-db (pl-at-goal "atom(42)" {}) (pl-mk-trail))
+  false)
+(pl-at-test!
+  "atom(f(x)) fails"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atom(f(x))" {})
+    (pl-mk-trail))
+  false)
+
+;; ── number/1 + integer/1 ──
+
+(pl-at-test!
+  "number(42) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "number(42)" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "number(foo) fails"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "number(foo)" {})
+    (pl-mk-trail))
+  false)
+(pl-at-test!
+  "integer(7) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "integer(7)" {})
+    (pl-mk-trail))
+  true)
+
+;; ── compound/1 + callable/1 + atomic/1 ──
+
+(pl-at-test!
+  "compound(f(x)) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "compound(f(x))" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "compound(foo) fails"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "compound(foo)" {})
+    (pl-mk-trail))
+  false)
+(pl-at-test!
+  "callable(foo) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "callable(foo)" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "callable(f(x)) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "callable(f(x))" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "callable(42) fails"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "callable(42)" {})
+    (pl-mk-trail))
+  false)
+(pl-at-test!
+  "atomic(foo) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atomic(foo)" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "atomic(42) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atomic(42)" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "atomic(f(x)) fails"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atomic(f(x))" {})
+    (pl-mk-trail))
+  false)
+
+;; ── is_list/1 ──
+
+(pl-at-test!
+  "is_list([]) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "is_list([])" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "is_list([1,2,3]) succeeds"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "is_list([1,2,3])" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "is_list(foo) fails"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "is_list(foo)" {})
+    (pl-mk-trail))
+  false)
+
+;; ── atom_length/2 ──
+
+(define pl-at-env-al {})
+(pl-solve-once!
+  pl-at-db
+  (pl-at-goal "atom_length(hello, N)" pl-at-env-al)
+  (pl-mk-trail))
+(pl-at-test!
+  "atom_length(hello, N) -> N=5"
+  (pl-num-val (pl-walk-deep (dict-get pl-at-env-al "N")))
+  5)
+(pl-at-test!
+  "atom_length empty atom"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atom_length('', 0)" {})
+    (pl-mk-trail))
+  true)
+
+;; ── atom_concat/3 ──
+
+(define pl-at-env-ac {})
+(pl-solve-once!
+  pl-at-db
+  (pl-at-goal "atom_concat(foo, bar, X)" pl-at-env-ac)
+  (pl-mk-trail))
+(pl-at-test!
+  "atom_concat(foo, bar, X) -> X=foobar"
+  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-ac "X")))
+  "foobar")
+
+(pl-at-test!
+  "atom_concat(foo, bar, foobar) check"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atom_concat(foo, bar, foobar)" {})
+    (pl-mk-trail))
+  true)
+(pl-at-test!
+  "atom_concat(foo, bar, foobaz) fails"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atom_concat(foo, bar, foobaz)" {})
+    (pl-mk-trail))
+  false)
+
+(define pl-at-env-ac2 {})
+(pl-solve-once!
+  pl-at-db
+  (pl-at-goal "atom_concat(foo, Y, foobar)" pl-at-env-ac2)
+  (pl-mk-trail))
+(pl-at-test!
+  "atom_concat(foo, Y, foobar) -> Y=bar"
+  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-ac2 "Y")))
+  "bar")
+
+;; ── atom_chars/2 ──
+
+(define pl-at-env-ach {})
+(pl-solve-once!
+  pl-at-db
+  (pl-at-goal "atom_chars(cat, Cs)" pl-at-env-ach)
+  (pl-mk-trail))
+(pl-at-test!
+  "atom_chars(cat, Cs) -> Cs=[c,a,t]"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "atom_chars(cat, [c,a,t])" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-at-env-ach2 {})
+(pl-solve-once!
+  pl-at-db
+  (pl-at-goal "atom_chars(A, [h,i])" pl-at-env-ach2)
+  (pl-mk-trail))
+(pl-at-test!
+  "atom_chars(A, [h,i]) -> A=hi"
+  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-ach2 "A")))
+  "hi")
+
+;; ── char_code/2 ──
+
+(define pl-at-env-cc {})
+(pl-solve-once!
+  pl-at-db
+  (pl-at-goal "char_code(a, N)" pl-at-env-cc)
+  (pl-mk-trail))
+(pl-at-test!
+  "char_code(a, N) -> N=97"
+  (pl-num-val (pl-walk-deep (dict-get pl-at-env-cc "N")))
+  97)
+
+(define pl-at-env-cc2 {})
+(pl-solve-once!
+  pl-at-db
+  (pl-at-goal "char_code(C, 65)" pl-at-env-cc2)
+  (pl-mk-trail))
+(pl-at-test!
+  "char_code(C, 65) -> C='A'"
+  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-cc2 "C")))
+  "A")
+
+;; ── number_codes/2 ──
+
+(pl-at-test!
+  "number_codes(42, [52,50])"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "number_codes(42, [52,50])" {})
+    (pl-mk-trail))
+  true)
+
+;; ── number_chars/2 ──
+
+(pl-at-test!
+  "number_chars(42, ['4','2'])"
+  (pl-solve-once!
+    pl-at-db
+    (pl-at-goal "number_chars(42, ['4','2'])" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-atom-tests-run! (fn () {:failed pl-at-test-fail :passed pl-at-test-pass :total pl-at-test-count :failures pl-at-test-failures}))

lib/prolog/tests/char_predicates.sx

@@ -0,0 +1,290 @@
+;; lib/prolog/tests/char_predicates.sx — char_type/2, upcase_atom/2, downcase_atom/2,
+;;   string_upper/2, string_lower/2
+
+(define pl-cp-test-count 0)
+(define pl-cp-test-pass 0)
+(define pl-cp-test-fail 0)
+(define pl-cp-test-failures (list))
+
+(define
+  pl-cp-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-cp-test-count (+ pl-cp-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-cp-test-pass (+ pl-cp-test-pass 1))
+        (begin
+          (set! pl-cp-test-fail (+ pl-cp-test-fail 1))
+          (append!
+            pl-cp-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-cp-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-cp-db (pl-mk-db))
+
+;; ─── char_type/2 — alpha ──────────────────────────────────────────
+
+(pl-cp-test!
+  "char_type(a, alpha) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(a, alpha)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "char_type('1', alpha) fails"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type('1', alpha)" {})
+    (pl-mk-trail))
+  false)
+
+(pl-cp-test!
+  "char_type('A', alpha) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type('A', alpha)" {})
+    (pl-mk-trail))
+  true)
+
+;; ─── char_type/2 — alnum ─────────────────────────────────────────
+
+(pl-cp-test!
+  "char_type('5', alnum) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type('5', alnum)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "char_type(a, alnum) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(a, alnum)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "char_type(' ', alnum) fails"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(' ', alnum)" {})
+    (pl-mk-trail))
+  false)
+
+;; ─── char_type/2 — digit ─────────────────────────────────────────
+
+(pl-cp-test!
+  "char_type('5', digit) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type('5', digit)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "char_type(a, digit) fails"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(a, digit)" {})
+    (pl-mk-trail))
+  false)
+
+;; ─── char_type/2 — digit(Weight) ─────────────────────────────────
+
+(define pl-cp-env-dw {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "char_type('5', digit(N))" pl-cp-env-dw)
+  (pl-mk-trail))
+(pl-cp-test!
+  "char_type('5', digit(N)) -> N=5"
+  (pl-num-val (pl-walk-deep (dict-get pl-cp-env-dw "N")))
+  5)
+
+(define pl-cp-env-dw0 {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "char_type('0', digit(N))" pl-cp-env-dw0)
+  (pl-mk-trail))
+(pl-cp-test!
+  "char_type('0', digit(N)) -> N=0"
+  (pl-num-val (pl-walk-deep (dict-get pl-cp-env-dw0 "N")))
+  0)
+
+;; ─── char_type/2 — space/white ───────────────────────────────────
+
+(pl-cp-test!
+  "char_type(' ', space) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(' ', space)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "char_type(a, space) fails"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(a, space)" {})
+    (pl-mk-trail))
+  false)
+
+;; ─── char_type/2 — upper(Lower) ──────────────────────────────────
+
+(define pl-cp-env-ul {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "char_type('A', upper(L))" pl-cp-env-ul)
+  (pl-mk-trail))
+(pl-cp-test!
+  "char_type('A', upper(L)) -> L=a"
+  (pl-atom-name (pl-walk-deep (dict-get pl-cp-env-ul "L")))
+  "a")
+
+(pl-cp-test!
+  "char_type(a, upper(L)) fails — not uppercase"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(a, upper(_))" {})
+    (pl-mk-trail))
+  false)
+
+;; ─── char_type/2 — lower(Upper) ──────────────────────────────────
+
+(define pl-cp-env-lu {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "char_type(a, lower(U))" pl-cp-env-lu)
+  (pl-mk-trail))
+(pl-cp-test!
+  "char_type(a, lower(U)) -> U='A'"
+  (pl-atom-name (pl-walk-deep (dict-get pl-cp-env-lu "U")))
+  "A")
+
+;; ─── char_type/2 — ascii(Code) ───────────────────────────────────
+
+(define pl-cp-env-as {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "char_type(a, ascii(C))" pl-cp-env-as)
+  (pl-mk-trail))
+(pl-cp-test!
+  "char_type(a, ascii(C)) -> C=97"
+  (pl-num-val (pl-walk-deep (dict-get pl-cp-env-as "C")))
+  97)
+
+;; ─── char_type/2 — punct ─────────────────────────────────────────
+
+(pl-cp-test!
+  "char_type('.', punct) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type('.', punct)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "char_type(a, punct) fails"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "char_type(a, punct)" {})
+    (pl-mk-trail))
+  false)
+
+;; ─── upcase_atom/2 ───────────────────────────────────────────────
+
+(define pl-cp-env-ua {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "upcase_atom(hello, X)" pl-cp-env-ua)
+  (pl-mk-trail))
+(pl-cp-test!
+  "upcase_atom(hello, X) -> X='HELLO'"
+  (pl-atom-name (pl-walk-deep (dict-get pl-cp-env-ua "X")))
+  "HELLO")
+
+(pl-cp-test!
+  "upcase_atom(hello, 'HELLO') succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "upcase_atom(hello, 'HELLO')" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "upcase_atom('Hello World', 'HELLO WORLD') succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "upcase_atom('Hello World', 'HELLO WORLD')" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "upcase_atom('', '') succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "upcase_atom('', '')" {})
+    (pl-mk-trail))
+  true)
+
+;; ─── downcase_atom/2 ─────────────────────────────────────────────
+
+(define pl-cp-env-da {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "downcase_atom('HELLO', X)" pl-cp-env-da)
+  (pl-mk-trail))
+(pl-cp-test!
+  "downcase_atom('HELLO', X) -> X=hello"
+  (pl-atom-name (pl-walk-deep (dict-get pl-cp-env-da "X")))
+  "hello")
+
+(pl-cp-test!
+  "downcase_atom('HELLO', hello) succeeds"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "downcase_atom('HELLO', hello)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-cp-test!
+  "downcase_atom(hello, hello) succeeds — already lowercase"
+  (pl-solve-once!
+    pl-cp-db
+    (pl-cp-goal "downcase_atom(hello, hello)" {})
+    (pl-mk-trail))
+  true)
+
+;; ─── string_upper/2 + string_lower/2 (aliases) ───────────────────
+
+(define pl-cp-env-su {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "string_upper(hello, X)" pl-cp-env-su)
+  (pl-mk-trail))
+(pl-cp-test!
+  "string_upper(hello, X) -> X='HELLO'"
+  (pl-atom-name (pl-walk-deep (dict-get pl-cp-env-su "X")))
+  "HELLO")
+
+(define pl-cp-env-sl {})
+(pl-solve-once!
+  pl-cp-db
+  (pl-cp-goal "string_lower('WORLD', X)" pl-cp-env-sl)
+  (pl-mk-trail))
+(pl-cp-test!
+  "string_lower('WORLD', X) -> X=world"
+  (pl-atom-name (pl-walk-deep (dict-get pl-cp-env-sl "X")))
+  "world")
+
+(define pl-char-predicates-tests-run! (fn () {:failed pl-cp-test-fail :passed pl-cp-test-pass :total pl-cp-test-count :failures pl-cp-test-failures}))

lib/prolog/tests/clausedb.sx

@@ -0,0 +1,99 @@
+;; lib/prolog/tests/clausedb.sx — Clause DB unit tests
+
+(define pl-db-test-count 0)
+(define pl-db-test-pass 0)
+(define pl-db-test-fail 0)
+(define pl-db-test-failures (list))
+
+(define
+  pl-db-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-db-test-count (+ pl-db-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-db-test-pass (+ pl-db-test-pass 1))
+        (begin
+          (set! pl-db-test-fail (+ pl-db-test-fail 1))
+          (append!
+            pl-db-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(pl-db-test!
+  "head-key atom arity 0"
+  (pl-head-key (nth (first (pl-parse "foo.")) 1))
+  "foo/0")
+
+(pl-db-test!
+  "head-key compound arity 2"
+  (pl-head-key (nth (first (pl-parse "bar(a, b).")) 1))
+  "bar/2")
+
+(pl-db-test!
+  "clause-key of :- clause"
+  (pl-clause-key (first (pl-parse "likes(mary, X) :- friendly(X).")))
+  "likes/2")
+
+(pl-db-test!
+  "empty db lookup returns empty list"
+  (len (pl-db-lookup (pl-mk-db) "parent/2"))
+  0)
+
+(define pl-db-t1 (pl-mk-db))
+(pl-db-load! pl-db-t1 (pl-parse "foo(a). foo(b). foo(c)."))
+
+(pl-db-test!
+  "three facts same functor"
+  (len (pl-db-lookup pl-db-t1 "foo/1"))
+  3)
+(pl-db-test!
+  "mismatching key returns empty"
+  (len (pl-db-lookup pl-db-t1 "foo/2"))
+  0)
+
+(pl-db-test!
+  "first clause has arg a"
+  (pl-atom-name
+    (first (pl-args (nth (first (pl-db-lookup pl-db-t1 "foo/1")) 1))))
+  "a")
+
+(pl-db-test!
+  "third clause has arg c"
+  (pl-atom-name
+    (first (pl-args (nth (nth (pl-db-lookup pl-db-t1 "foo/1") 2) 1))))
+  "c")
+
+(define pl-db-t2 (pl-mk-db))
+(pl-db-load! pl-db-t2 (pl-parse "foo. bar. foo. parent(a, b). parent(c, d)."))
+
+(pl-db-test!
+  "atom heads keyed as foo/0"
+  (len (pl-db-lookup pl-db-t2 "foo/0"))
+  2)
+(pl-db-test!
+  "atom heads keyed as bar/0"
+  (len (pl-db-lookup pl-db-t2 "bar/0"))
+  1)
+(pl-db-test!
+  "compound heads keyed as parent/2"
+  (len (pl-db-lookup pl-db-t2 "parent/2"))
+  2)
+
+(pl-db-test!
+  "lookup-goal extracts functor/arity"
+  (len
+    (pl-db-lookup-goal pl-db-t2 (nth (first (pl-parse "parent(X, Y).")) 1)))
+  2)
+
+(pl-db-test!
+  "lookup-goal on atom goal"
+  (len (pl-db-lookup-goal pl-db-t2 (nth (first (pl-parse "foo.")) 1)))
+  2)
+
+(pl-db-test!
+  "stored clause is clause form"
+  (first (first (pl-db-lookup pl-db-t2 "parent/2")))
+  "clause")
+
+(define pl-clausedb-tests-run! (fn () {:failed pl-db-test-fail :passed pl-db-test-pass :total pl-db-test-count :failures pl-db-test-failures}))

lib/prolog/tests/compiler.sx

@@ -0,0 +1,185 @@
+;; lib/prolog/tests/compiler.sx — compiled clause dispatch tests
+
+(define pl-cmp-test-count 0)
+(define pl-cmp-test-pass 0)
+(define pl-cmp-test-fail 0)
+(define pl-cmp-test-failures (list))
+
+(define
+  pl-cmp-test!
+  (fn
+    (name got expected)
+    (set! pl-cmp-test-count (+ pl-cmp-test-count 1))
+    (if
+      (= got expected)
+      (set! pl-cmp-test-pass (+ pl-cmp-test-pass 1))
+      (begin
+        (set! pl-cmp-test-fail (+ pl-cmp-test-fail 1))
+        (append! pl-cmp-test-failures name)))))
+
+;; Load src, compile, return DB.
+(define
+  pl-cmp-mk
+  (fn
+    (src)
+    (let
+      ((db (pl-mk-db)))
+      (pl-db-load! db (pl-parse src))
+      (pl-compile-db! db)
+      db)))
+
+;; Run goal string against compiled DB; return bool (instantiates vars).
+(define
+  pl-cmp-once
+  (fn
+    (db src)
+    (pl-solve-once!
+      db
+      (pl-instantiate (pl-parse-goal src) {})
+      (pl-mk-trail))))
+
+;; Count solutions for goal string against compiled DB.
+(define
+  pl-cmp-count
+  (fn
+    (db src)
+    (pl-solve-count!
+      db
+      (pl-instantiate (pl-parse-goal src) {})
+      (pl-mk-trail))))
+
+;; ── 1. Simple facts ──────────────────────────────────────────────
+
+(define pl-cmp-db1 (pl-cmp-mk "color(red). color(green). color(blue)."))
+
+(pl-cmp-test! "compiled fact hit" (pl-cmp-once pl-cmp-db1 "color(red)") true)
+(pl-cmp-test!
+  "compiled fact miss"
+  (pl-cmp-once pl-cmp-db1 "color(yellow)")
+  false)
+(pl-cmp-test! "compiled fact count" (pl-cmp-count pl-cmp-db1 "color(X)") 3)
+
+;; ── 2. Recursive rule: append ────────────────────────────────────
+
+(define
+  pl-cmp-db2
+  (pl-cmp-mk "append([], L, L). append([H|T], L, [H|R]) :- append(T, L, R)."))
+
+(pl-cmp-test!
+  "compiled append build"
+  (pl-cmp-once pl-cmp-db2 "append([1,2],[3],[1,2,3])")
+  true)
+(pl-cmp-test!
+  "compiled append fail"
+  (pl-cmp-once pl-cmp-db2 "append([1,2],[3],[1,2])")
+  false)
+(pl-cmp-test!
+  "compiled append split count"
+  (pl-cmp-count pl-cmp-db2 "append(X, Y, [a,b])")
+  3)
+
+;; ── 3. Cut ───────────────────────────────────────────────────────
+
+(define
+  pl-cmp-db3
+  (pl-cmp-mk "first(X, [X|_]) :- !. first(X, [_|T]) :- first(X, T)."))
+
+(pl-cmp-test!
+  "compiled cut: only one solution"
+  (pl-cmp-count pl-cmp-db3 "first(X, [a,b,c])")
+  1)
+
+(let
+  ((db pl-cmp-db3) (trail (pl-mk-trail)) (env {}))
+  (let
+    ((x (pl-mk-rt-var "X")))
+    (dict-set! env "X" x)
+    (pl-solve-once!
+      db
+      (pl-instantiate (pl-parse-goal "first(X, [a,b,c])") env)
+      trail)
+    (pl-cmp-test!
+      "compiled cut: correct binding"
+      (pl-atom-name (pl-walk x))
+      "a")))
+
+;; ── 4. member ────────────────────────────────────────────────────
+
+(define
+  pl-cmp-db4
+  (pl-cmp-mk "member(X, [X|_]). member(X, [_|T]) :- member(X, T)."))
+
+(pl-cmp-test!
+  "compiled member hit"
+  (pl-cmp-once pl-cmp-db4 "member(b, [a,b,c])")
+  true)
+(pl-cmp-test!
+  "compiled member miss"
+  (pl-cmp-once pl-cmp-db4 "member(d, [a,b,c])")
+  false)
+(pl-cmp-test!
+  "compiled member count"
+  (pl-cmp-count pl-cmp-db4 "member(X, [a,b,c])")
+  3)
+
+;; ── 5. Arithmetic in body ────────────────────────────────────────
+
+(define pl-cmp-db5 (pl-cmp-mk "double(X, Y) :- Y is X * 2."))
+
+(let
+  ((db pl-cmp-db5) (trail (pl-mk-trail)) (env {}))
+  (let
+    ((y (pl-mk-rt-var "Y")))
+    (dict-set! env "Y" y)
+    (pl-solve-once!
+      db
+      (pl-instantiate (pl-parse-goal "double(5, Y)") env)
+      trail)
+    (pl-cmp-test! "compiled arithmetic in body" (pl-num-val (pl-walk y)) 10)))
+
+;; ── 6. Transitive ancestor ───────────────────────────────────────
+
+(define
+  pl-cmp-db6
+  (pl-cmp-mk
+    (str
+      "parent(a,b). parent(b,c). parent(c,d)."
+      "ancestor(X,Y) :- parent(X,Y)."
+      "ancestor(X,Y) :- parent(X,Z), ancestor(Z,Y).")))
+
+(pl-cmp-test!
+  "compiled ancestor direct"
+  (pl-cmp-once pl-cmp-db6 "ancestor(a,b)")
+  true)
+(pl-cmp-test!
+  "compiled ancestor 3-step"
+  (pl-cmp-once pl-cmp-db6 "ancestor(a,d)")
+  true)
+(pl-cmp-test!
+  "compiled ancestor fail"
+  (pl-cmp-once pl-cmp-db6 "ancestor(d,a)")
+  false)
+
+;; ── 7. Fallback: uncompiled predicate calls compiled sub-predicate
+
+(define
+  pl-cmp-db7
+  (let
+    ((db (pl-mk-db)))
+    (pl-db-load! db (pl-parse "q(1). q(2)."))
+    (pl-compile-db! db)
+    (pl-db-load! db (pl-parse "r(X) :- q(X)."))
+    db))
+
+(pl-cmp-test!
+  "uncompiled predicate resolves"
+  (pl-cmp-once pl-cmp-db7 "r(1)")
+  true)
+(pl-cmp-test!
+  "uncompiled calls compiled sub-pred count"
+  (pl-cmp-count pl-cmp-db7 "r(X)")
+  2)
+
+;; ── Runner ───────────────────────────────────────────────────────
+
+(define pl-compiler-tests-run! (fn () {:failed pl-cmp-test-fail :passed pl-cmp-test-pass :total pl-cmp-test-count :failures pl-cmp-test-failures}))

lib/prolog/tests/cross_validate.sx

@@ -0,0 +1,86 @@
+;; lib/prolog/tests/cross_validate.sx
+;; Verifies that the compiled solver produces the same solution counts as the
+;; interpreter for each classic program + built-in exercise.
+;; Interpreter is the reference: if they disagree, the compiler is wrong.
+
+(define pl-xv-test-count 0)
+(define pl-xv-test-pass 0)
+(define pl-xv-test-fail 0)
+(define pl-xv-test-failures (list))
+
+(define
+  pl-xv-test!
+  (fn
+    (name got expected)
+    (set! pl-xv-test-count (+ pl-xv-test-count 1))
+    (if
+      (= got expected)
+      (set! pl-xv-test-pass (+ pl-xv-test-pass 1))
+      (begin
+        (set! pl-xv-test-fail (+ pl-xv-test-fail 1))
+        (append! pl-xv-test-failures name)))))
+
+;; Shorthand: assert compiled result matches interpreter.
+(define
+  pl-xv-match!
+  (fn
+    (name src goal)
+    (pl-xv-test! name (pl-compiled-matches-interp? src goal) true)))
+
+;; ── 1. append/3 ─────────────────────────────────────────────────
+
+(define
+  pl-xv-append
+  "append([], L, L). append([H|T], L, [H|R]) :- append(T, L, R).")
+
+(pl-xv-match! "append build 2+2" pl-xv-append "append([1,2],[3,4],X)")
+(pl-xv-match! "append split [a,b,c]" pl-xv-append "append(X, Y, [a,b,c])")
+(pl-xv-match! "append member-mode" pl-xv-append "append(_, [3], [1,2,3])")
+
+;; ── 2. member/2 ─────────────────────────────────────────────────
+
+(define pl-xv-member "member(X, [X|_]). member(X, [_|T]) :- member(X, T).")
+
+(pl-xv-match! "member check hit" pl-xv-member "member(b, [a,b,c])")
+(pl-xv-match! "member count" pl-xv-member "member(X, [a,b,c])")
+(pl-xv-match! "member empty" pl-xv-member "member(X, [])")
+
+;; ── 3. facts + transitive rules ─────────────────────────────────
+
+(define
+  pl-xv-ancestor
+  (str
+    "parent(a,b). parent(b,c). parent(c,d). parent(a,c)."
+    "ancestor(X,Y) :- parent(X,Y)."
+    "ancestor(X,Y) :- parent(X,Z), ancestor(Z,Y)."))
+
+(pl-xv-match! "ancestor direct" pl-xv-ancestor "ancestor(a,b)")
+(pl-xv-match! "ancestor transitive" pl-xv-ancestor "ancestor(a,d)")
+(pl-xv-match! "ancestor all from a" pl-xv-ancestor "ancestor(a,Y)")
+
+;; ── 4. cut semantics ────────────────────────────────────────────
+
+(define pl-xv-cut "first(X,[X|_]) :- !. first(X,[_|T]) :- first(X,T).")
+
+(pl-xv-match! "cut one solution" pl-xv-cut "first(X,[a,b,c])")
+(pl-xv-match! "cut empty list" pl-xv-cut "first(X,[])")
+
+;; ── 5. arithmetic ───────────────────────────────────────────────
+
+(define pl-xv-arith "sq(X,Y) :- Y is X * X. even(X) :- 0 is X mod 2.")
+
+(pl-xv-match! "sq(3,Y) count" pl-xv-arith "sq(3,Y)")
+(pl-xv-match! "sq(3,9) check" pl-xv-arith "sq(3,9)")
+(pl-xv-match! "even(4) check" pl-xv-arith "even(4)")
+(pl-xv-match! "even(3) check" pl-xv-arith "even(3)")
+
+;; ── 6. if-then-else ─────────────────────────────────────────────
+
+(define pl-xv-ite "classify(X, pos) :- X > 0, !. classify(_, nonpos).")
+
+(pl-xv-match! "classify positive" pl-xv-ite "classify(5, C)")
+(pl-xv-match! "classify zero" pl-xv-ite "classify(0, C)")
+
+;; ── Runner ───────────────────────────────────────────────────────
+
+(define pl-cross-validate-tests-run! (fn () {:failed pl-xv-test-fail :passed pl-xv-test-pass :total pl-xv-test-count :failures pl-xv-test-failures}))

lib/prolog/tests/dynamic.sx

@@ -0,0 +1,158 @@
+;; lib/prolog/tests/dynamic.sx — assert/asserta/assertz/retract.
+
+(define pl-dy-test-count 0)
+(define pl-dy-test-pass 0)
+(define pl-dy-test-fail 0)
+(define pl-dy-test-failures (list))
+
+(define
+  pl-dy-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-dy-test-count (+ pl-dy-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-dy-test-pass (+ pl-dy-test-pass 1))
+        (begin
+          (set! pl-dy-test-fail (+ pl-dy-test-fail 1))
+          (append!
+            pl-dy-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-dy-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+;; assertz then query
+(define pl-dy-db1 (pl-mk-db))
+(pl-solve-once!
+  pl-dy-db1
+  (pl-dy-goal "assertz(foo(1))" {})
+  (pl-mk-trail))
+(pl-dy-test!
+  "assertz(foo(1)) + foo(1)"
+  (pl-solve-once! pl-dy-db1 (pl-dy-goal "foo(1)" {}) (pl-mk-trail))
+  true)
+
+(pl-dy-test!
+  "after one assertz, foo/1 has 1 clause"
+  (pl-solve-count! pl-dy-db1 (pl-dy-goal "foo(X)" {}) (pl-mk-trail))
+  1)
+
+;; assertz appends — order preserved
+(define pl-dy-db2 (pl-mk-db))
+(pl-solve-once!
+  pl-dy-db2
+  (pl-dy-goal "assertz(p(1))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-dy-db2
+  (pl-dy-goal "assertz(p(2))" {})
+  (pl-mk-trail))
+(pl-dy-test!
+  "assertz twice — count 2"
+  (pl-solve-count! pl-dy-db2 (pl-dy-goal "p(X)" {}) (pl-mk-trail))
+  2)
+
+(define pl-dy-env-a {})
+(pl-solve-once! pl-dy-db2 (pl-dy-goal "p(X)" pl-dy-env-a) (pl-mk-trail))
+(pl-dy-test!
+  "assertz: first solution is the first asserted (1)"
+  (pl-num-val (pl-walk-deep (dict-get pl-dy-env-a "X")))
+  1)
+
+;; asserta prepends
+(define pl-dy-db3 (pl-mk-db))
+(pl-solve-once!
+  pl-dy-db3
+  (pl-dy-goal "assertz(p(1))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-dy-db3
+  (pl-dy-goal "asserta(p(99))" {})
+  (pl-mk-trail))
+(define pl-dy-env-b {})
+(pl-solve-once! pl-dy-db3 (pl-dy-goal "p(X)" pl-dy-env-b) (pl-mk-trail))
+(pl-dy-test!
+  "asserta: prepended clause is first solution"
+  (pl-num-val (pl-walk-deep (dict-get pl-dy-env-b "X")))
+  99)
+
+;; assert/1 = assertz/1
+(define pl-dy-db4 (pl-mk-db))
+(pl-solve-once!
+  pl-dy-db4
+  (pl-dy-goal "assert(g(7))" {})
+  (pl-mk-trail))
+(pl-dy-test!
+  "assert/1 alias"
+  (pl-solve-once! pl-dy-db4 (pl-dy-goal "g(7)" {}) (pl-mk-trail))
+  true)
+
+;; retract removes a fact
+(define pl-dy-db5 (pl-mk-db))
+(pl-solve-once!
+  pl-dy-db5
+  (pl-dy-goal "assertz(q(1))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-dy-db5
+  (pl-dy-goal "assertz(q(2))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-dy-db5
+  (pl-dy-goal "assertz(q(3))" {})
+  (pl-mk-trail))
+(pl-dy-test!
+  "before retract: 3 clauses"
+  (pl-solve-count! pl-dy-db5 (pl-dy-goal "q(X)" {}) (pl-mk-trail))
+  3)
+(pl-solve-once!
+  pl-dy-db5
+  (pl-dy-goal "retract(q(2))" {})
+  (pl-mk-trail))
+(pl-dy-test!
+  "after retract(q(2)): 2 clauses left"
+  (pl-solve-count! pl-dy-db5 (pl-dy-goal "q(X)" {}) (pl-mk-trail))
+  2)
+
+(define pl-dy-env-c {})
+(pl-solve-once! pl-dy-db5 (pl-dy-goal "q(X)" pl-dy-env-c) (pl-mk-trail))
+(pl-dy-test!
+  "after retract(q(2)): first remaining is 1"
+  (pl-num-val (pl-walk-deep (dict-get pl-dy-env-c "X")))
+  1)
+
+;; retract of non-existent
+(pl-dy-test!
+  "retract(missing(0)) on empty db fails"
+  (pl-solve-once!
+    (pl-mk-db)
+    (pl-dy-goal "retract(missing(0))" {})
+    (pl-mk-trail))
+  false)
+
+;; retract with unbound var matches first
+(define pl-dy-db6 (pl-mk-db))
+(pl-solve-once!
+  pl-dy-db6
+  (pl-dy-goal "assertz(r(11))" {})
+  (pl-mk-trail))
+(pl-solve-once!
+  pl-dy-db6
+  (pl-dy-goal "assertz(r(22))" {})
+  (pl-mk-trail))
+(define pl-dy-env-d {})
+(pl-solve-once!
+  pl-dy-db6
+  (pl-dy-goal "retract(r(X))" pl-dy-env-d)
+  (pl-mk-trail))
+(pl-dy-test!
+  "retract(r(X)) binds X to first match"
+  (pl-num-val (pl-walk-deep (dict-get pl-dy-env-d "X")))
+  11)
+
+(define pl-dynamic-tests-run! (fn () {:failed pl-dy-test-fail :passed pl-dy-test-pass :total pl-dy-test-count :failures pl-dy-test-failures}))

lib/prolog/tests/findall.sx

@@ -0,0 +1,167 @@
+;; lib/prolog/tests/findall.sx — findall/3, bagof/3, setof/3.
+
+(define pl-fb-test-count 0)
+(define pl-fb-test-pass 0)
+(define pl-fb-test-fail 0)
+(define pl-fb-test-failures (list))
+
+(define
+  pl-fb-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-fb-test-count (+ pl-fb-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-fb-test-pass (+ pl-fb-test-pass 1))
+        (begin
+          (set! pl-fb-test-fail (+ pl-fb-test-fail 1))
+          (append!
+            pl-fb-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-fb-term-to-sx
+  (fn
+    (t)
+    (cond
+      ((pl-num? t) (pl-num-val t))
+      ((pl-atom? t) (pl-atom-name t))
+      (true (list :complex)))))
+
+(define
+  pl-fb-list-walked
+  (fn
+    (w)
+    (cond
+      ((and (pl-atom? w) (= (pl-atom-name w) "[]")) (list))
+      ((and (pl-compound? w) (= (pl-fun w) ".") (= (len (pl-args w)) 2))
+        (cons
+          (pl-fb-term-to-sx (first (pl-args w)))
+          (pl-fb-list-walked (nth (pl-args w) 1))))
+      (true (list :not-list)))))
+
+(define pl-fb-list-to-sx (fn (t) (pl-fb-list-walked (pl-walk-deep t))))
+
+(define
+  pl-fb-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-fb-prog-src "member(X, [X|_]). member(X, [_|T]) :- member(X, T).")
+
+(define pl-fb-db (pl-mk-db))
+(pl-db-load! pl-fb-db (pl-parse pl-fb-prog-src))
+
+;; ── findall ──
+
+(define pl-fb-env-1 {})
+(pl-solve-once!
+  pl-fb-db
+  (pl-fb-goal "findall(X, member(X, [a, b, c]), L)" pl-fb-env-1)
+  (pl-mk-trail))
+(pl-fb-test!
+  "findall member [a, b, c]"
+  (pl-fb-list-to-sx (dict-get pl-fb-env-1 "L"))
+  (list "a" "b" "c"))
+
+(define pl-fb-env-2 {})
+(pl-solve-once!
+  pl-fb-db
+  (pl-fb-goal "findall(X, (member(X, [1, 2, 3]), X >= 2), L)" pl-fb-env-2)
+  (pl-mk-trail))
+(pl-fb-test!
+  "findall with comparison filter"
+  (pl-fb-list-to-sx (dict-get pl-fb-env-2 "L"))
+  (list 2 3))
+
+(define pl-fb-env-3 {})
+(pl-solve-once!
+  pl-fb-db
+  (pl-fb-goal "findall(X, fail, L)" pl-fb-env-3)
+  (pl-mk-trail))
+(pl-fb-test!
+  "findall on fail succeeds with empty list"
+  (pl-fb-list-to-sx (dict-get pl-fb-env-3 "L"))
+  (list))
+
+(pl-fb-test!
+  "findall(X, fail, L) the goal succeeds"
+  (pl-solve-once!
+    pl-fb-db
+    (pl-fb-goal "findall(X, fail, L)" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-fb-env-4 {})
+(pl-solve-once!
+  pl-fb-db
+  (pl-fb-goal
+    "findall(p(X, Y), (member(X, [1, 2]), member(Y, [a, b])), L)"
+    pl-fb-env-4)
+  (pl-mk-trail))
+(pl-fb-test!
+  "findall over compound template — count = 4"
+  (len (pl-fb-list-to-sx (dict-get pl-fb-env-4 "L")))
+  4)
+
+;; ── bagof ──
+
+(pl-fb-test!
+  "bagof succeeds when results exist"
+  (pl-solve-once!
+    pl-fb-db
+    (pl-fb-goal "bagof(X, member(X, [1, 2, 3]), L)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-fb-test!
+  "bagof fails on empty"
+  (pl-solve-once!
+    pl-fb-db
+    (pl-fb-goal "bagof(X, fail, L)" {})
+    (pl-mk-trail))
+  false)
+
+(define pl-fb-env-5 {})
+(pl-solve-once!
+  pl-fb-db
+  (pl-fb-goal "bagof(X, member(X, [c, a, b]), L)" pl-fb-env-5)
+  (pl-mk-trail))
+(pl-fb-test!
+  "bagof preserves order"
+  (pl-fb-list-to-sx (dict-get pl-fb-env-5 "L"))
+  (list "c" "a" "b"))
+
+;; ── setof ──
+
+(define pl-fb-env-6 {})
+(pl-solve-once!
+  pl-fb-db
+  (pl-fb-goal "setof(X, member(X, [c, a, b, a, c]), L)" pl-fb-env-6)
+  (pl-mk-trail))
+(pl-fb-test!
+  "setof sorts + dedupes atoms"
+  (pl-fb-list-to-sx (dict-get pl-fb-env-6 "L"))
+  (list "a" "b" "c"))
+
+(pl-fb-test!
+  "setof fails on empty"
+  (pl-solve-once!
+    pl-fb-db
+    (pl-fb-goal "setof(X, fail, L)" {})
+    (pl-mk-trail))
+  false)
+
+(define pl-fb-env-7 {})
+(pl-solve-once!
+  pl-fb-db
+  (pl-fb-goal "setof(X, member(X, [3, 1, 2, 1, 3]), L)" pl-fb-env-7)
+  (pl-mk-trail))
+(pl-fb-test!
+  "setof sorts + dedupes nums"
+  (pl-fb-list-to-sx (dict-get pl-fb-env-7 "L"))
+  (list 1 2 3))
+
+(define pl-findall-tests-run! (fn () {:failed pl-fb-test-fail :passed pl-fb-test-pass :total pl-fb-test-count :failures pl-fb-test-failures}))

lib/prolog/tests/hs_bridge.sx

@@ -0,0 +1,165 @@
+;; lib/prolog/tests/hs_bridge.sx — tests for Prolog↔Hyperscript bridge
+;;
+;; Verifies pl-hs-query, pl-hs-predicate/N, and pl-hs-install.
+;; Also demonstrates the end-to-end DSL pattern:
+;;   (define allowed (pl-hs-predicate/2 db "allowed"))
+;;   → (allowed "alice" "edit") is what Hyperscript compiles
+;;     `when allowed(alice, edit)` to.
+
+(define pl-hsb-test-count 0)
+(define pl-hsb-test-pass 0)
+(define pl-hsb-test-fail 0)
+(define pl-hsb-test-failures (list))
+
+(define
+  pl-hsb-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-hsb-test-count (+ pl-hsb-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-hsb-test-pass (+ pl-hsb-test-pass 1))
+        (begin
+          (set! pl-hsb-test-fail (+ pl-hsb-test-fail 1))
+          (append!
+            pl-hsb-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+;; ── shared KB ──
+
+(define
+  pl-hsb-perm-src
+  "role(alice, admin). role(bob, editor). role(charlie, viewer). permission(admin, read). permission(admin, write). permission(admin, delete). permission(editor, read). permission(editor, write). permission(viewer, read). allowed(U, A) :- role(U, R), permission(R, A).")
+
+(define pl-hsb-db (pl-load pl-hsb-perm-src))
+
+;; ── pl-hs-query ──
+
+(pl-hsb-test!
+  "pl-hs-query: ground fact succeeds"
+  (pl-hs-query pl-hsb-db "role(alice, admin)")
+  true)
+
+(pl-hsb-test!
+  "pl-hs-query: absent fact fails"
+  (pl-hs-query pl-hsb-db "role(alice, viewer)")
+  false)
+
+(pl-hsb-test!
+  "pl-hs-query: rule derivation succeeds"
+  (pl-hs-query pl-hsb-db "allowed(alice, delete)")
+  true)
+
+(pl-hsb-test!
+  "pl-hs-query: rule derivation fails"
+  (pl-hs-query pl-hsb-db "allowed(charlie, delete)")
+  false)
+
+(pl-hsb-test!
+  "pl-hs-query: arithmetic goal"
+  (pl-hs-query pl-hsb-db "X is 3 + 4, X = 7")
+  true)
+
+;; ── pl-hs-predicate/2 ──
+
+(define pl-hsb-allowed (pl-hs-predicate/2 pl-hsb-db "allowed"))
+
+(pl-hsb-test!
+  "predicate/2: alice can read"
+  (pl-hsb-allowed "alice" "read")
+  true)
+
+(pl-hsb-test!
+  "predicate/2: alice can delete"
+  (pl-hsb-allowed "alice" "delete")
+  true)
+
+(pl-hsb-test!
+  "predicate/2: charlie cannot write"
+  (pl-hsb-allowed "charlie" "write")
+  false)
+
+(pl-hsb-test!
+  "predicate/2: bob can write"
+  (pl-hsb-allowed "bob" "write")
+  true)
+
+(pl-hsb-test!
+  "predicate/2: unknown user fails"
+  (pl-hsb-allowed "eve" "read")
+  false)
+
+;; ── DSL simulation ──
+;; Hyperscript compiles `when allowed(user, action) then …`
+;; to `(allowed user action)` — a direct SX function call.
+;; Here we verify that pattern works end-to-end.
+
+(define pl-hsb-user "alice")
+(define pl-hsb-action "write")
+
+(pl-hsb-test!
+  "DSL simulation: (allowed user action) true path"
+  (pl-hsb-allowed pl-hsb-user pl-hsb-action)
+  true)
+
+(define pl-hsb-user2 "charlie")
+
+(pl-hsb-test!
+  "DSL simulation: (allowed user action) false path"
+  (pl-hsb-allowed pl-hsb-user2 pl-hsb-action)
+  false)
+
+;; ── pl-hs-predicate/1 ──
+
+(define pl-hsb-viewer-src "color(red). color(green). color(blue).")
+(define pl-hsb-color-db (pl-load pl-hsb-viewer-src))
+(define pl-hsb-color? (pl-hs-predicate/1 pl-hsb-color-db "color"))
+
+(pl-hsb-test! "predicate/1: color(red) succeeds" (pl-hsb-color? "red") true)
+
+(pl-hsb-test!
+  "predicate/1: color(purple) fails"
+  (pl-hsb-color? "purple")
+  false)
+
+;; ── pl-hs-predicate/3 ──
+
+(define pl-hsb-3ary-src "between_vals(X, Lo, Hi) :- X >= Lo, X =< Hi.")
+(define pl-hsb-3ary-db (pl-load pl-hsb-3ary-src))
+(define pl-hsb-in-range? (pl-hs-predicate/3 pl-hsb-3ary-db "between_vals"))
+
+(pl-hsb-test!
+  "predicate/3: 5 in range [1,10]"
+  (pl-hsb-in-range? "5" "1" "10")
+  true)
+
+(pl-hsb-test!
+  "predicate/3: 15 not in range [1,10]"
+  (pl-hsb-in-range? "15" "1" "10")
+  false)
+
+;; ── pl-hs-install ──
+
+(define
+  pl-hsb-installed
+  (pl-hs-install
+    pl-hsb-db
+    (list (list "allowed" 2) (list "role" 2) (list "permission" 2))))
+
+(pl-hsb-test!
+  "pl-hs-install: returns dict with allowed key"
+  (not (nil? (dict-get pl-hsb-installed "allowed")))
+  true)
+
+(pl-hsb-test!
+  "pl-hs-install: installed allowed fn works"
+  ((dict-get pl-hsb-installed "allowed") "alice" "delete")
+  true)
+
+(pl-hsb-test!
+  "pl-hs-install: installed role fn works"
+  ((dict-get pl-hsb-installed "role") "bob" "editor")
+  true)
+
+(define pl-hs-bridge-tests-run! (fn () {:failed pl-hsb-test-fail :passed pl-hsb-test-pass :total pl-hsb-test-count :failures pl-hsb-test-failures}))

lib/prolog/tests/integration.sx

@@ -0,0 +1,172 @@
+;; lib/prolog/tests/integration.sx — end-to-end integration tests via pl-query-* API
+;;
+;; Tests the full source→parse→load→solve pipeline with real programs.
+;; Covers: permission system, graph reachability, quicksort, fibonacci, dynamic KB.
+
+(define pl-int-test-count 0)
+(define pl-int-test-pass 0)
+(define pl-int-test-fail 0)
+(define pl-int-test-failures (list))
+
+(define
+  pl-int-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-int-test-count (+ pl-int-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-int-test-pass (+ pl-int-test-pass 1))
+        (begin
+          (set! pl-int-test-fail (+ pl-int-test-fail 1))
+          (append!
+            pl-int-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+;; ── Permission system ──
+;; role/2 + permission/2 facts, allowed/2 rule
+
+(define
+  pl-int-perm-src
+  "role(alice, admin). role(bob, editor). role(charlie, viewer). permission(admin, read). permission(admin, write). permission(admin, delete). permission(editor, read). permission(editor, write). permission(viewer, read). allowed(U, A) :- role(U, R), permission(R, A).")
+
+(define pl-int-perm-db (pl-load pl-int-perm-src))
+
+(pl-int-test!
+  "alice can read"
+  (len (pl-query-all pl-int-perm-db "allowed(alice, read)"))
+  1)
+
+(pl-int-test!
+  "alice can delete"
+  (len (pl-query-all pl-int-perm-db "allowed(alice, delete)"))
+  1)
+
+(pl-int-test!
+  "charlie cannot write"
+  (len (pl-query-all pl-int-perm-db "allowed(charlie, write)"))
+  0)
+
+(pl-int-test!
+  "alice has 3 permissions"
+  (len (pl-query-all pl-int-perm-db "allowed(alice, A)"))
+  3)
+
+(pl-int-test!
+  "only one user can delete"
+  (len (pl-query-all pl-int-perm-db "allowed(U, delete)"))
+  1)
+
+(pl-int-test!
+  "the deleter is alice"
+  (dict-get (first (pl-query-all pl-int-perm-db "allowed(U, delete)")) "U")
+  "alice")
+
+;; ── Graph reachability ──
+;; Directed edges; path/2 transitive closure via two clauses
+
+(define
+  pl-int-graph-src
+  "edge(a, b). edge(b, c). edge(c, d). edge(b, d). path(X, Y) :- edge(X, Y). path(X, Y) :- edge(X, Z), path(Z, Y).")
+
+(define pl-int-graph-db (pl-load pl-int-graph-src))
+
+(pl-int-test!
+  "direct edge a→b is a path"
+  (len (pl-query-all pl-int-graph-db "path(a, b)"))
+  1)
+
+(pl-int-test!
+  "transitive path a→c"
+  (len (pl-query-all pl-int-graph-db "path(a, c)"))
+  1)
+
+(pl-int-test!
+  "no path d→a (no back-edges)"
+  (len (pl-query-all pl-int-graph-db "path(d, a)"))
+  0)
+
+(pl-int-test!
+  "4 derivations from a (b,c,d via two routes to d)"
+  (len (pl-query-all pl-int-graph-db "path(a, Y)"))
+  4)
+
+;; ── Quicksort ──
+;; Partition-and-recurse; uses its own append/3 to avoid DB pollution
+
+(define
+  pl-int-qs-src
+  "partition(_, [], [], []). partition(Piv, [H|T], [H|Less], Greater) :- H =< Piv, !, partition(Piv, T, Less, Greater). partition(Piv, [H|T], Less, [H|Greater]) :- partition(Piv, T, Less, Greater). append([], L, L). append([H|T], L, [H|R]) :- append(T, L, R). quicksort([], []). quicksort([H|T], Sorted) :- partition(H, T, Less, Greater), quicksort(Less, SL), quicksort(Greater, SG), append(SL, [H|SG], Sorted).")
+
+(define pl-int-qs-db (pl-load pl-int-qs-src))
+
+(pl-int-test!
+  "quicksort([]) = [] (ground check)"
+  (len (pl-query-all pl-int-qs-db "quicksort([], [])"))
+  1)
+
+(pl-int-test!
+  "quicksort([3,1,2]) = [1,2,3] (ground check)"
+  (len (pl-query-all pl-int-qs-db "quicksort([3,1,2], [1,2,3])"))
+  1)
+
+(pl-int-test!
+  "quicksort([5,3,1,4,2]) = [1,2,3,4,5] (ground check)"
+  (len (pl-query-all pl-int-qs-db "quicksort([5,3,1,4,2], [1,2,3,4,5])"))
+  1)
+
+(pl-int-test!
+  "quicksort([3,1,2], [3,1,2]) fails — unsorted order rejected"
+  (len (pl-query-all pl-int-qs-db "quicksort([3,1,2], [3,1,2])"))
+  0)
+
+;; ── Fibonacci ──
+;; Naive recursive; ground checks avoid list-format uncertainty
+
+(define
+  pl-int-fib-src
+  "fib(0, 0). fib(1, 1). fib(N, F) :- N > 1, N1 is N - 1, N2 is N - 2, fib(N1, F1), fib(N2, F2), F is F1 + F2.")
+
+(define pl-int-fib-db (pl-load pl-int-fib-src))
+
+(pl-int-test!
+  "fib(0, 0) succeeds"
+  (len (pl-query-all pl-int-fib-db "fib(0, 0)"))
+  1)
+
+(pl-int-test!
+  "fib(5, 5) succeeds"
+  (len (pl-query-all pl-int-fib-db "fib(5, 5)"))
+  1)
+
+(pl-int-test!
+  "fib(7, 13) succeeds"
+  (len (pl-query-all pl-int-fib-db "fib(7, 13)"))
+  1)
+
+;; ── Dynamic knowledge base ──
+;; Assert and retract facts; the DB dict is mutable so mutations persist
+
+(define pl-int-dyn-src "color(red). color(green). color(blue).")
+(define pl-int-dyn-db (pl-load pl-int-dyn-src))
+
+(pl-int-test!
+  "initial KB: 3 colors"
+  (len (pl-query-all pl-int-dyn-db "color(X)"))
+  3)
+
+(pl-int-test!
+  "after assert(color(yellow)): 4 colors"
+  (begin
+    (pl-query-all pl-int-dyn-db "assert(color(yellow))")
+    (len (pl-query-all pl-int-dyn-db "color(X)")))
+  4)
+
+(pl-int-test!
+  "after retract(color(red)): back to 3 colors"
+  (begin
+    (pl-query-all pl-int-dyn-db "retract(color(red))")
+    (len (pl-query-all pl-int-dyn-db "color(X)")))
+  3)
+
+(define pl-integration-tests-run! (fn () {:failed pl-int-test-fail :passed pl-int-test-pass :total pl-int-test-count :failures pl-int-test-failures}))

lib/prolog/tests/io_predicates.sx

@@ -0,0 +1,326 @@
+;; lib/prolog/tests/io_predicates.sx — term_to_atom/2, term_string/2,
+;;   with_output_to/2, writeln/1, format/1, format/2
+
+(define pl-io-test-count 0)
+(define pl-io-test-pass 0)
+(define pl-io-test-fail 0)
+(define pl-io-test-failures (list))
+
+(define
+  pl-io-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-io-test-count (+ pl-io-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-io-test-pass (+ pl-io-test-pass 1))
+        (begin
+          (set! pl-io-test-fail (+ pl-io-test-fail 1))
+          (append!
+            pl-io-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-io-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-io-db (pl-mk-db))
+
+;; helper: get output buffer after running a goal
+(define
+  pl-io-capture!
+  (fn
+    (goal)
+    (do
+      (pl-output-clear!)
+      (pl-solve-once! pl-io-db goal (pl-mk-trail))
+      pl-output-buffer)))
+
+;; ─── term_to_atom/2 — bound Term direction ─────────────────────────────────
+
+(pl-io-test!
+  "term_to_atom(foo(a,b), A) — compound"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "term_to_atom(foo(a,b), A)" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "A"))))
+  "foo(a, b)")
+
+(pl-io-test!
+  "term_to_atom(hello, A) — atom"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "term_to_atom(hello, A)" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "A"))))
+  "hello")
+
+(pl-io-test!
+  "term_to_atom(42, A) — number"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "term_to_atom(42, A)" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "A"))))
+  "42")
+
+(pl-io-test!
+  "term_to_atom(foo(a,b), 'foo(a, b)') — succeeds when Atom matches"
+  (pl-solve-once!
+    pl-io-db
+    (pl-io-goal "term_to_atom(foo(a,b), 'foo(a, b)')" {})
+    (pl-mk-trail))
+  true)
+
+(pl-io-test!
+  "term_to_atom(hello, world) — fails on mismatch"
+  (pl-solve-once!
+    pl-io-db
+    (pl-io-goal "term_to_atom(hello, world)" {})
+    (pl-mk-trail))
+  false)
+
+;; ─── term_to_atom/2 — parse direction (Atom bound, Term unbound) ───────────
+
+(pl-io-test!
+  "term_to_atom(T, 'foo(a)') — parse direction gives compound"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "term_to_atom(T, 'foo(a)')" env)
+      (pl-mk-trail))
+    (let
+      ((t (pl-walk-deep (dict-get env "T"))))
+      (and (pl-compound? t) (= (pl-fun t) "foo"))))
+  true)
+
+(pl-io-test!
+  "term_to_atom(T, hello) — parse direction gives atom"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "term_to_atom(T, hello)" env)
+      (pl-mk-trail))
+    (let
+      ((t (pl-walk-deep (dict-get env "T"))))
+      (and (pl-atom? t) (= (pl-atom-name t) "hello"))))
+  true)
+
+;; ─── term_string/2 — alias ──────────────────────────────────────────────────
+
+(pl-io-test!
+  "term_string(bar(x), A) — same as term_to_atom"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "term_string(bar(x), A)" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "A"))))
+  "bar(x)")
+
+(pl-io-test!
+  "term_string(42, A) — number to string"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "term_string(42, A)" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "A"))))
+  "42")
+
+;; ─── writeln/1 ─────────────────────────────────────────────────────────────
+
+(pl-io-test!
+  "writeln(hello) writes 'hello\n'"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), writeln(hello))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "hello
+")
+
+(pl-io-test!
+  "writeln(42) writes '42\n'"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), writeln(42))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "42
+")
+
+;; ─── with_output_to/2 ──────────────────────────────────────────────────────
+
+(pl-io-test!
+  "with_output_to(atom(X), write(foo)) — captures write output"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), write(foo))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "foo")
+
+(pl-io-test!
+  "with_output_to(atom(X), (write(a), write(b))) — concat output"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), (write(a), write(b)))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "ab")
+
+(pl-io-test!
+  "with_output_to(atom(X), nl) — captures newline"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), nl)" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "
+")
+
+(pl-io-test!
+  "with_output_to(atom(X), true) — captures empty string"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), true)" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "")
+
+(pl-io-test!
+  "with_output_to(string(X), write(hello)) — string sink works"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(string(X), write(hello))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "hello")
+
+(pl-io-test!
+  "with_output_to(atom(X), fail) — fails when goal fails"
+  (pl-solve-once!
+    pl-io-db
+    (pl-io-goal "with_output_to(atom(X), fail)" {})
+    (pl-mk-trail))
+  false)
+
+;; ─── format/1 ──────────────────────────────────────────────────────────────
+
+(pl-io-test!
+  "format('hello~n') — tilde-n becomes newline"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), format('hello~n'))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "hello
+")
+
+(pl-io-test!
+  "format('~~') — double tilde becomes single tilde"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), format('~~'))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "~")
+
+(pl-io-test!
+  "format('abc') — plain text passes through"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), format(abc))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "abc")
+
+;; ─── format/2 ──────────────────────────────────────────────────────────────
+
+(pl-io-test!
+  "format('~w+~w', [1,2]) — two ~w args"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), format('~w+~w', [1,2]))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "1+2")
+
+(pl-io-test!
+  "format('hello ~a!', [world]) — ~a with atom arg"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), format('hello ~a!', [world]))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "hello world!")
+
+(pl-io-test!
+  "format('n=~d', [42]) — ~d with integer arg"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), format('n=~d', [42]))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "n=42")
+
+(pl-io-test!
+  "format('~w', [foo(a)]) — ~w with compound"
+  (let
+    ((env {}))
+    (pl-solve-once!
+      pl-io-db
+      (pl-io-goal "with_output_to(atom(X), format('~w', [foo(a)]))" env)
+      (pl-mk-trail))
+    (pl-atom-name (pl-walk-deep (dict-get env "X"))))
+  "foo(a)")
+
+(define
+  pl-io-predicates-tests-run!
+  (fn
+    ()
+    {:failed pl-io-test-fail
+      :passed pl-io-test-pass
+      :total pl-io-test-count
+      :failures pl-io-test-failures}))

lib/prolog/tests/iso_predicates.sx

@@ -0,0 +1,320 @@
+;; lib/prolog/tests/iso_predicates.sx — succ/2, plus/3, between/3, length/2, last/2, nth0/3, nth1/3, max/min arith
+
+(define pl-ip-test-count 0)
+(define pl-ip-test-pass 0)
+(define pl-ip-test-fail 0)
+(define pl-ip-test-failures (list))
+
+(define
+  pl-ip-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-ip-test-count (+ pl-ip-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-ip-test-pass (+ pl-ip-test-pass 1))
+        (begin
+          (set! pl-ip-test-fail (+ pl-ip-test-fail 1))
+          (append!
+            pl-ip-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-ip-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-ip-db (pl-mk-db))
+
+;; ── succ/2 ──
+
+(define pl-ip-env-s1 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "succ(3, X)" pl-ip-env-s1)
+  (pl-mk-trail))
+(pl-ip-test!
+  "succ(3, X) → X=4"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-s1 "X")))
+  4)
+
+(define pl-ip-env-s2 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "succ(0, X)" pl-ip-env-s2)
+  (pl-mk-trail))
+(pl-ip-test!
+  "succ(0, X) → X=1"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-s2 "X")))
+  1)
+
+(define pl-ip-env-s3 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "succ(X, 5)" pl-ip-env-s3)
+  (pl-mk-trail))
+(pl-ip-test!
+  "succ(X, 5) → X=4"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-s3 "X")))
+  4)
+
+(pl-ip-test!
+  "succ(X, 0) fails"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "succ(X, 0)" {})
+    (pl-mk-trail))
+  false)
+
+;; ── plus/3 ──
+
+(define pl-ip-env-p1 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "plus(2, 3, X)" pl-ip-env-p1)
+  (pl-mk-trail))
+(pl-ip-test!
+  "plus(2, 3, X) → X=5"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-p1 "X")))
+  5)
+
+(define pl-ip-env-p2 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "plus(2, X, 7)" pl-ip-env-p2)
+  (pl-mk-trail))
+(pl-ip-test!
+  "plus(2, X, 7) → X=5"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-p2 "X")))
+  5)
+
+(define pl-ip-env-p3 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "plus(X, 3, 7)" pl-ip-env-p3)
+  (pl-mk-trail))
+(pl-ip-test!
+  "plus(X, 3, 7) → X=4"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-p3 "X")))
+  4)
+
+(pl-ip-test!
+  "plus(0, 0, 0) succeeds"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "plus(0, 0, 0)" {})
+    (pl-mk-trail))
+  true)
+
+;; ── between/3 ──
+
+(pl-ip-test!
+  "between(1, 3, X): 3 solutions"
+  (pl-solve-count!
+    pl-ip-db
+    (pl-ip-goal "between(1, 3, X)" {})
+    (pl-mk-trail))
+  3)
+
+(pl-ip-test!
+  "between(1, 3, 2) succeeds"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "between(1, 3, 2)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-ip-test!
+  "between(1, 3, 5) fails"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "between(1, 3, 5)" {})
+    (pl-mk-trail))
+  false)
+
+(pl-ip-test!
+  "between(5, 3, X): 0 solutions (empty range)"
+  (pl-solve-count!
+    pl-ip-db
+    (pl-ip-goal "between(5, 3, X)" {})
+    (pl-mk-trail))
+  0)
+
+(define pl-ip-env-b1 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "between(1, 5, X)" pl-ip-env-b1)
+  (pl-mk-trail))
+(pl-ip-test!
+  "between(1, 5, X): first solution X=1"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-b1 "X")))
+  1)
+
+(pl-ip-test!
+  "between + condition: between(1,5,X), X > 3 → 2 solutions"
+  (pl-solve-count!
+    pl-ip-db
+    (pl-ip-goal "between(1, 5, X), X > 3" {})
+    (pl-mk-trail))
+  2)
+
+;; ── length/2 ──
+
+(define pl-ip-env-l1 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "length([1,2,3], N)" pl-ip-env-l1)
+  (pl-mk-trail))
+(pl-ip-test!
+  "length([1,2,3], N) → N=3"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-l1 "N")))
+  3)
+
+(define pl-ip-env-l2 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "length([], N)" pl-ip-env-l2)
+  (pl-mk-trail))
+(pl-ip-test!
+  "length([], N) → N=0"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-l2 "N")))
+  0)
+
+(pl-ip-test!
+  "length([a,b], 2) check succeeds"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "length([a,b], 2)" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-ip-env-l3 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "length(L, 3)" pl-ip-env-l3)
+  (pl-mk-trail))
+(pl-ip-test!
+  "length(L, 3): L is a list of length 3"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "length(L, 3), is_list(L)" pl-ip-env-l3)
+    (pl-mk-trail))
+  true)
+
+;; ── last/2 ──
+
+(define pl-ip-env-la1 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "last([1,2,3], X)" pl-ip-env-la1)
+  (pl-mk-trail))
+(pl-ip-test!
+  "last([1,2,3], X) → X=3"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-la1 "X")))
+  3)
+
+(define pl-ip-env-la2 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "last([a], X)" pl-ip-env-la2)
+  (pl-mk-trail))
+(pl-ip-test!
+  "last([a], X) → X=a"
+  (pl-atom-name (pl-walk-deep (dict-get pl-ip-env-la2 "X")))
+  "a")
+
+(pl-ip-test!
+  "last([], X) fails"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "last([], X)" {})
+    (pl-mk-trail))
+  false)
+
+;; ── nth0/3 ──
+
+(define pl-ip-env-n0 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "nth0(0, [a,b,c], X)" pl-ip-env-n0)
+  (pl-mk-trail))
+(pl-ip-test!
+  "nth0(0, [a,b,c], X) → X=a"
+  (pl-atom-name (pl-walk-deep (dict-get pl-ip-env-n0 "X")))
+  "a")
+
+(define pl-ip-env-n1 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "nth0(2, [a,b,c], X)" pl-ip-env-n1)
+  (pl-mk-trail))
+(pl-ip-test!
+  "nth0(2, [a,b,c], X) → X=c"
+  (pl-atom-name (pl-walk-deep (dict-get pl-ip-env-n1 "X")))
+  "c")
+
+(pl-ip-test!
+  "nth0(5, [a,b,c], X) fails"
+  (pl-solve-once!
+    pl-ip-db
+    (pl-ip-goal "nth0(5, [a,b,c], X)" {})
+    (pl-mk-trail))
+  false)
+
+;; ── nth1/3 ──
+
+(define pl-ip-env-n1a {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "nth1(1, [a,b,c], X)" pl-ip-env-n1a)
+  (pl-mk-trail))
+(pl-ip-test!
+  "nth1(1, [a,b,c], X) → X=a"
+  (pl-atom-name (pl-walk-deep (dict-get pl-ip-env-n1a "X")))
+  "a")
+
+(define pl-ip-env-n1b {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "nth1(3, [a,b,c], X)" pl-ip-env-n1b)
+  (pl-mk-trail))
+(pl-ip-test!
+  "nth1(3, [a,b,c], X) → X=c"
+  (pl-atom-name (pl-walk-deep (dict-get pl-ip-env-n1b "X")))
+  "c")
+
+;; ── max/min in arithmetic ──
+
+(define pl-ip-env-m1 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "X is max(3, 5)" pl-ip-env-m1)
+  (pl-mk-trail))
+(pl-ip-test!
+  "X is max(3, 5) → X=5"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-m1 "X")))
+  5)
+
+(define pl-ip-env-m2 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "X is min(3, 5)" pl-ip-env-m2)
+  (pl-mk-trail))
+(pl-ip-test!
+  "X is min(3, 5) → X=3"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-m2 "X")))
+  3)
+
+(define pl-ip-env-m3 {})
+(pl-solve-once!
+  pl-ip-db
+  (pl-ip-goal "X is max(7, 2) + min(1, 4)" pl-ip-env-m3)
+  (pl-mk-trail))
+(pl-ip-test!
+  "X is max(7,2) + min(1,4) → X=8"
+  (pl-num-val (pl-walk-deep (dict-get pl-ip-env-m3 "X")))
+  8)
+
+(define pl-iso-predicates-tests-run! (fn () {:failed pl-ip-test-fail :passed pl-ip-test-pass :total pl-ip-test-count :failures pl-ip-test-failures}))

lib/prolog/tests/list_predicates.sx

@@ -0,0 +1,335 @@
+;; lib/prolog/tests/list_predicates.sx — ==/2, \==/2, flatten/2, numlist/3,
+;;   atomic_list_concat/2,3, sum_list/2, max_list/2, min_list/2, delete/3
+
+(define pl-lp-test-count 0)
+(define pl-lp-test-pass 0)
+(define pl-lp-test-fail 0)
+(define pl-lp-test-failures (list))
+
+(define
+  pl-lp-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-lp-test-count (+ pl-lp-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-lp-test-pass (+ pl-lp-test-pass 1))
+        (begin
+          (set! pl-lp-test-fail (+ pl-lp-test-fail 1))
+          (append!
+            pl-lp-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-lp-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-lp-db (pl-mk-db))
+
+;; ── ==/2 ───────────────────────────────────────────────────────────
+
+(pl-lp-test!
+  "==(a, a) succeeds"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "==(a, a)" {}) (pl-mk-trail))
+  true)
+
+(pl-lp-test!
+  "==(a, b) fails"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "==(a, b)" {}) (pl-mk-trail))
+  false)
+
+(pl-lp-test!
+  "==(1, 1) succeeds"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "==(1, 1)" {}) (pl-mk-trail))
+  true)
+
+(pl-lp-test!
+  "==(1, 2) fails"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "==(1, 2)" {}) (pl-mk-trail))
+  false)
+
+(pl-lp-test!
+  "==(f(a,b), f(a,b)) succeeds"
+  (pl-solve-once!
+    pl-lp-db
+    (pl-lp-goal "==(f(a,b), f(a,b))" {})
+    (pl-mk-trail))
+  true)
+
+(pl-lp-test!
+  "==(f(a,b), f(a,c)) fails"
+  (pl-solve-once!
+    pl-lp-db
+    (pl-lp-goal "==(f(a,b), f(a,c))" {})
+    (pl-mk-trail))
+  false)
+
+;; unbound var vs atom: fails (different tags)
+(pl-lp-test!
+  "==(X, a) fails (unbound var vs atom)"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "==(X, a)" {}) (pl-mk-trail))
+  false)
+
+;; two unbound vars with SAME name in same env share the same runtime var
+(define pl-lp-env-same-var {})
+(pl-lp-goal "==(X, X)" pl-lp-env-same-var)
+(pl-lp-test!
+  "==(X, X) succeeds (same runtime var)"
+  (pl-solve-once!
+    pl-lp-db
+    (pl-instantiate
+      (nth (first (pl-parse "g :- ==(X, X).")) 2)
+      pl-lp-env-same-var)
+    (pl-mk-trail))
+  true)
+
+;; ── \==/2 ──────────────────────────────────────────────────────────
+
+(pl-lp-test!
+  "\\==(a, b) succeeds"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "\\==(a, b)" {}) (pl-mk-trail))
+  true)
+
+(pl-lp-test!
+  "\\==(a, a) fails"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "\\==(a, a)" {}) (pl-mk-trail))
+  false)
+
+(pl-lp-test!
+  "\\==(X, a) succeeds (unbound var differs from atom)"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "\\==(X, a)" {}) (pl-mk-trail))
+  true)
+
+(pl-lp-test!
+  "\\==(1, 2) succeeds"
+  (pl-solve-once! pl-lp-db (pl-lp-goal "\\==(1, 2)" {}) (pl-mk-trail))
+  true)
+
+;; ── flatten/2 ──────────────────────────────────────────────────────
+
+(define pl-lp-env-fl1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "flatten([], F)" pl-lp-env-fl1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "flatten([], []) -> empty"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-fl1 "F")))
+  "[]")
+
+(define pl-lp-env-fl2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "flatten([1,2,3], F)" pl-lp-env-fl2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "flatten([1,2,3], F) -> [1,2,3]"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-fl2 "F")))
+  ".(1, .(2, .(3, [])))")
+
+(define pl-lp-env-fl3 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "flatten([1,[2,[3]],4], F)" pl-lp-env-fl3)
+  (pl-mk-trail))
+(pl-lp-test!
+  "flatten([1,[2,[3]],4], F) -> [1,2,3,4]"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-fl3 "F")))
+  ".(1, .(2, .(3, .(4, []))))")
+
+(define pl-lp-env-fl4 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "flatten([[a,b],[c]], F)" pl-lp-env-fl4)
+  (pl-mk-trail))
+(pl-lp-test!
+  "flatten([[a,b],[c]], F) -> [a,b,c]"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-fl4 "F")))
+  ".(a, .(b, .(c, [])))")
+
+;; ── numlist/3 ──────────────────────────────────────────────────────
+
+(define pl-lp-env-nl1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "numlist(1, 5, L)" pl-lp-env-nl1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "numlist(1,5,L) -> [1,2,3,4,5]"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-nl1 "L")))
+  ".(1, .(2, .(3, .(4, .(5, [])))))")
+
+(define pl-lp-env-nl2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "numlist(3, 3, L)" pl-lp-env-nl2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "numlist(3,3,L) -> [3]"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-nl2 "L")))
+  ".(3, [])")
+
+(pl-lp-test!
+  "numlist(5, 3, L) fails (Low > High)"
+  (pl-solve-once!
+    pl-lp-db
+    (pl-lp-goal "numlist(5, 3, L)" {})
+    (pl-mk-trail))
+  false)
+
+;; ── atomic_list_concat/2 ───────────────────────────────────────────
+
+(define pl-lp-env-alc1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "atomic_list_concat([a, b, c], R)" pl-lp-env-alc1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "atomic_list_concat([a,b,c], R) -> abc"
+  (pl-atom-name (pl-walk-deep (dict-get pl-lp-env-alc1 "R")))
+  "abc")
+
+(define pl-lp-env-alc2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "atomic_list_concat([hello, world], R)" pl-lp-env-alc2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "atomic_list_concat([hello,world], R) -> helloworld"
+  (pl-atom-name (pl-walk-deep (dict-get pl-lp-env-alc2 "R")))
+  "helloworld")
+
+;; ── atomic_list_concat/3 ───────────────────────────────────────────
+
+(define pl-lp-env-alcs1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "atomic_list_concat([a, b, c], '-', R)" pl-lp-env-alcs1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "atomic_list_concat([a,b,c], '-', R) -> a-b-c"
+  (pl-atom-name (pl-walk-deep (dict-get pl-lp-env-alcs1 "R")))
+  "a-b-c")
+
+(define pl-lp-env-alcs2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "atomic_list_concat([x], '-', R)" pl-lp-env-alcs2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "atomic_list_concat([x], '-', R) -> x (single element, no sep)"
+  (pl-atom-name (pl-walk-deep (dict-get pl-lp-env-alcs2 "R")))
+  "x")
+
+;; ── sum_list/2 ─────────────────────────────────────────────────────
+
+(define pl-lp-env-sl1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "sum_list([1,2,3], S)" pl-lp-env-sl1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "sum_list([1,2,3], S) -> 6"
+  (pl-num-val (pl-walk-deep (dict-get pl-lp-env-sl1 "S")))
+  6)
+
+(define pl-lp-env-sl2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "sum_list([10], S)" pl-lp-env-sl2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "sum_list([10], S) -> 10"
+  (pl-num-val (pl-walk-deep (dict-get pl-lp-env-sl2 "S")))
+  10)
+
+(define pl-lp-env-sl3 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "sum_list([], S)" pl-lp-env-sl3)
+  (pl-mk-trail))
+(pl-lp-test!
+  "sum_list([], S) -> 0"
+  (pl-num-val (pl-walk-deep (dict-get pl-lp-env-sl3 "S")))
+  0)
+
+;; ── max_list/2 ─────────────────────────────────────────────────────
+
+(define pl-lp-env-mx1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "max_list([3,1,4,1,5,9,2,6], M)" pl-lp-env-mx1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "max_list([3,1,4,1,5,9,2,6], M) -> 9"
+  (pl-num-val (pl-walk-deep (dict-get pl-lp-env-mx1 "M")))
+  9)
+
+(define pl-lp-env-mx2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "max_list([7], M)" pl-lp-env-mx2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "max_list([7], M) -> 7"
+  (pl-num-val (pl-walk-deep (dict-get pl-lp-env-mx2 "M")))
+  7)
+
+;; ── min_list/2 ─────────────────────────────────────────────────────
+
+(define pl-lp-env-mn1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "min_list([3,1,4,1,5,9,2,6], M)" pl-lp-env-mn1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "min_list([3,1,4,1,5,9,2,6], M) -> 1"
+  (pl-num-val (pl-walk-deep (dict-get pl-lp-env-mn1 "M")))
+  1)
+
+(define pl-lp-env-mn2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "min_list([5,2,8], M)" pl-lp-env-mn2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "min_list([5,2,8], M) -> 2"
+  (pl-num-val (pl-walk-deep (dict-get pl-lp-env-mn2 "M")))
+  2)
+
+;; ── delete/3 ───────────────────────────────────────────────────────
+
+(define pl-lp-env-del1 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "delete([1,2,3,2,1], 2, R)" pl-lp-env-del1)
+  (pl-mk-trail))
+(pl-lp-test!
+  "delete([1,2,3,2,1], 2, R) -> [1,3,1]"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-del1 "R")))
+  ".(1, .(3, .(1, [])))")
+
+(define pl-lp-env-del2 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "delete([a,b,c], d, R)" pl-lp-env-del2)
+  (pl-mk-trail))
+(pl-lp-test!
+  "delete([a,b,c], d, R) -> [a,b,c] (nothing deleted)"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-del2 "R")))
+  ".(a, .(b, .(c, [])))")
+
+(define pl-lp-env-del3 {})
+(pl-solve-once!
+  pl-lp-db
+  (pl-lp-goal "delete([], x, R)" pl-lp-env-del3)
+  (pl-mk-trail))
+(pl-lp-test!
+  "delete([], x, R) -> []"
+  (pl-format-term (pl-walk-deep (dict-get pl-lp-env-del3 "R")))
+  "[]")
+
+(define pl-list-predicates-tests-run! (fn () {:failed pl-lp-test-fail :passed pl-lp-test-pass :total pl-lp-test-count :failures pl-lp-test-failures}))

lib/prolog/tests/meta_call.sx

@@ -0,0 +1,197 @@
+;; lib/prolog/tests/meta_call.sx — forall/2, maplist/2, maplist/3, include/3, exclude/3
+(define pl-mc-test-count 0)
+(define pl-mc-test-pass 0)
+(define pl-mc-test-fail 0)
+(define pl-mc-test-failures (list))
+
+(define
+  pl-mc-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-mc-test-count (+ pl-mc-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-mc-test-pass (+ pl-mc-test-pass 1))
+        (begin
+          (set! pl-mc-test-fail (+ pl-mc-test-fail 1))
+          (append!
+            pl-mc-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-mc-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define
+  pl-mc-term-to-sx
+  (fn
+    (t)
+    (cond
+      ((pl-num? t) (pl-num-val t))
+      ((pl-atom? t) (pl-atom-name t))
+      (else t))))
+
+(define
+  pl-mc-list-sx
+  (fn
+    (t)
+    (let
+      ((w (pl-walk-deep t)))
+      (cond
+        ((and (pl-atom? w) (= (pl-atom-name w) "[]")) (list))
+        ((and (pl-compound? w) (= (pl-fun w) "."))
+          (cons
+            (pl-mc-term-to-sx (first (pl-args w)))
+            (pl-mc-list-sx (nth (pl-args w) 1))))
+        (else (list :not-list))))))
+
+(define pl-mc-db (pl-mk-db))
+
+(pl-db-load!
+  pl-mc-db
+  (pl-parse "member(X, [X|_]). member(X, [_|T]) :- member(X, T)."))
+
+(pl-db-load! pl-mc-db (pl-parse "double(X, Y) :- Y is X * 2."))
+
+(pl-db-load! pl-mc-db (pl-parse "even(X) :- 0 is X mod 2."))
+
+;; -- forall/2 --
+
+(pl-mc-test!
+  "forall(member(X,[2,4,6]), 0 is X mod 2) — all even"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "forall(member(X,[2,4,6]), 0 is X mod 2)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mc-test!
+  "forall(member(X,[2,3,6]), 0 is X mod 2) — 3 is odd, fails"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "forall(member(X,[2,3,6]), 0 is X mod 2)" {})
+    (pl-mk-trail))
+  false)
+
+(pl-mc-test!
+  "forall(member(_,[]), true) — vacuously true"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "forall(member(_,[]), true)" {})
+    (pl-mk-trail))
+  true)
+
+;; -- maplist/2 --
+
+(pl-mc-test!
+  "maplist(atom, [a,b,c]) — all atoms"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "maplist(atom, [a,b,c])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mc-test!
+  "maplist(atom, [a,1,c]) — 1 is not atom, fails"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "maplist(atom, [a,1,c])" {})
+    (pl-mk-trail))
+  false)
+
+(pl-mc-test!
+  "maplist(atom, []) — vacuously true"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "maplist(atom, [])" {})
+    (pl-mk-trail))
+  true)
+
+;; -- maplist/3 --
+
+(pl-mc-test!
+  "maplist(double, [1,2,3], [2,4,6]) — deterministic check"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "maplist(double, [1,2,3], [2,4,6])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mc-test!
+  "maplist(double, [1,2,3], [2,4,7]) — wrong result fails"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "maplist(double, [1,2,3], [2,4,7])" {})
+    (pl-mk-trail))
+  false)
+
+(define pl-mc-env-ml3 {:L (pl-mk-rt-var "L")})
+(pl-solve-once!
+  pl-mc-db
+  (pl-mc-goal "maplist(double, [1,2,3], L)" pl-mc-env-ml3)
+  (pl-mk-trail))
+(pl-mc-test!
+  "maplist(double, [1,2,3], L) — L bound to [2,4,6]"
+  (pl-mc-list-sx (dict-get pl-mc-env-ml3 "L"))
+  (list 2 4 6))
+
+;; -- include/3 --
+
+(pl-mc-test!
+  "include(even, [1,2,3,4,5,6], [2,4,6])"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "include(even, [1,2,3,4,5,6], [2,4,6])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mc-test!
+  "include(even, [], [])"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "include(even, [], [])" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-mc-env-inc {:R (pl-mk-rt-var "R")})
+(pl-solve-once!
+  pl-mc-db
+  (pl-mc-goal "include(even, [1,2,3,4,5,6], R)" pl-mc-env-inc)
+  (pl-mk-trail))
+(pl-mc-test!
+  "include(even, [1,2,3,4,5,6], R) — R bound to [2,4,6]"
+  (pl-mc-list-sx (dict-get pl-mc-env-inc "R"))
+  (list 2 4 6))
+
+;; -- exclude/3 --
+
+(pl-mc-test!
+  "exclude(even, [1,2,3,4,5,6], [1,3,5])"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "exclude(even, [1,2,3,4,5,6], [1,3,5])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mc-test!
+  "exclude(even, [], [])"
+  (pl-solve-once!
+    pl-mc-db
+    (pl-mc-goal "exclude(even, [], [])" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-mc-env-exc {:R (pl-mk-rt-var "R")})
+(pl-solve-once!
+  pl-mc-db
+  (pl-mc-goal "exclude(even, [1,2,3,4,5,6], R)" pl-mc-env-exc)
+  (pl-mk-trail))
+(pl-mc-test!
+  "exclude(even, [1,2,3,4,5,6], R) — R bound to [1,3,5]"
+  (pl-mc-list-sx (dict-get pl-mc-env-exc "R"))
+  (list 1 3 5))
+
+(define pl-meta-call-tests-run! (fn () {:failed pl-mc-test-fail :passed pl-mc-test-pass :total pl-mc-test-count :failures pl-mc-test-failures}))

lib/prolog/tests/meta_predicates.sx

@@ -0,0 +1,252 @@
+;; lib/prolog/tests/meta_predicates.sx — \+/1, not/1, once/1, ignore/1, ground/1, sort/2, msort/2, atom_number/2, number_string/2
+
+(define pl-mp-test-count 0)
+(define pl-mp-test-pass 0)
+(define pl-mp-test-fail 0)
+(define pl-mp-test-failures (list))
+
+(define
+  pl-mp-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-mp-test-count (+ pl-mp-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-mp-test-pass (+ pl-mp-test-pass 1))
+        (begin
+          (set! pl-mp-test-fail (+ pl-mp-test-fail 1))
+          (append!
+            pl-mp-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-mp-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define pl-mp-db (pl-mk-db))
+(pl-db-load!
+  pl-mp-db
+  (pl-parse "member(X, [X|_]). member(X, [_|T]) :- member(X, T)."))
+
+;; -- \+/1 --
+
+(pl-mp-test!
+  "\\+(fail) succeeds"
+  (pl-solve-once! pl-mp-db (pl-mp-goal "\\+(fail)" {}) (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "\\+(true) fails"
+  (pl-solve-once! pl-mp-db (pl-mp-goal "\\+(true)" {}) (pl-mk-trail))
+  false)
+
+(pl-mp-test!
+  "\\+(member(d, [a,b,c])) succeeds"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "\\+(member(d, [a,b,c]))" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "\\+(member(a, [a,b,c])) fails"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "\\+(member(a, [a,b,c]))" {})
+    (pl-mk-trail))
+  false)
+
+(define pl-mp-env-neg {})
+(pl-solve-once!
+  pl-mp-db
+  (pl-mp-goal "\\+(X = 5)" pl-mp-env-neg)
+  (pl-mk-trail))
+(pl-mp-test!
+  "\\+(X=5) fails, X stays unbound (bindings undone)"
+  (nil? (pl-var-binding (dict-get pl-mp-env-neg "X")))
+  true)
+
+;; -- not/1 --
+
+(pl-mp-test!
+  "not(fail) succeeds"
+  (pl-solve-once! pl-mp-db (pl-mp-goal "not(fail)" {}) (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "not(true) fails"
+  (pl-solve-once! pl-mp-db (pl-mp-goal "not(true)" {}) (pl-mk-trail))
+  false)
+
+;; -- once/1 --
+
+(pl-mp-test!
+  "once(member(X,[1,2,3])) succeeds once"
+  (pl-solve-count!
+    pl-mp-db
+    (pl-mp-goal "once(member(X,[1,2,3]))" {})
+    (pl-mk-trail))
+  1)
+
+(define pl-mp-env-once {})
+(pl-solve-once!
+  pl-mp-db
+  (pl-mp-goal "once(member(X,[1,2,3]))" pl-mp-env-once)
+  (pl-mk-trail))
+(pl-mp-test!
+  "once(member(X,[1,2,3])): X=1 (first solution)"
+  (pl-num-val (pl-walk-deep (dict-get pl-mp-env-once "X")))
+  1)
+
+(pl-mp-test!
+  "once(fail) fails"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "once(fail)" {})
+    (pl-mk-trail))
+  false)
+
+;; -- ignore/1 --
+
+(pl-mp-test!
+  "ignore(true) succeeds"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "ignore(true)" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "ignore(fail) still succeeds"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "ignore(fail)" {})
+    (pl-mk-trail))
+  true)
+
+;; -- ground/1 --
+
+(pl-mp-test!
+  "ground(foo(1, a)) succeeds"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "ground(foo(1, a))" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "ground(foo(X, a)) fails (X unbound)"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "ground(foo(X, a))" {})
+    (pl-mk-trail))
+  false)
+
+(pl-mp-test!
+  "ground(42) succeeds"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "ground(42)" {})
+    (pl-mk-trail))
+  true)
+
+;; -- sort/2 --
+
+(pl-mp-test!
+  "sort([b,a,c], [a,b,c])"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "sort([b,a,c], [a,b,c])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "sort([b,a,a,c], [a,b,c]) (removes duplicates)"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "sort([b,a,a,c], [a,b,c])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "sort([], [])"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "sort([], [])" {})
+    (pl-mk-trail))
+  true)
+
+;; -- msort/2 --
+
+(pl-mp-test!
+  "msort([b,a,a,c], [a,a,b,c]) (keeps duplicates)"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "msort([b,a,a,c], [a,a,b,c])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-mp-test!
+  "msort([3,1,2,1], [1,1,2,3])"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "msort([3,1,2,1], [1,1,2,3])" {})
+    (pl-mk-trail))
+  true)
+
+;; -- atom_number/2 --
+
+(define pl-mp-env-an1 {})
+(pl-solve-once!
+  pl-mp-db
+  (pl-mp-goal "atom_number('42', N)" pl-mp-env-an1)
+  (pl-mk-trail))
+(pl-mp-test!
+  "atom_number('42', N) -> N=42"
+  (pl-num-val (pl-walk-deep (dict-get pl-mp-env-an1 "N")))
+  42)
+
+(define pl-mp-env-an2 {})
+(pl-solve-once!
+  pl-mp-db
+  (pl-mp-goal "atom_number(A, 7)" pl-mp-env-an2)
+  (pl-mk-trail))
+(pl-mp-test!
+  "atom_number(A, 7) -> A='7'"
+  (pl-atom-name (pl-walk-deep (dict-get pl-mp-env-an2 "A")))
+  "7")
+
+(pl-mp-test!
+  "atom_number(foo, N) fails (not a number)"
+  (pl-solve-once!
+    pl-mp-db
+    (pl-mp-goal "atom_number(foo, N)" {})
+    (pl-mk-trail))
+  false)
+
+;; -- number_string/2 --
+
+(define pl-mp-env-ns1 {})
+(pl-solve-once!
+  pl-mp-db
+  (pl-mp-goal "number_string(42, S)" pl-mp-env-ns1)
+  (pl-mk-trail))
+(pl-mp-test!
+  "number_string(42, S) -> S='42'"
+  (pl-atom-name (pl-walk-deep (dict-get pl-mp-env-ns1 "S")))
+  "42")
+
+(define pl-mp-env-ns2 {})
+(pl-solve-once!
+  pl-mp-db
+  (pl-mp-goal "number_string(N, '3.14')" pl-mp-env-ns2)
+  (pl-mk-trail))
+(pl-mp-test!
+  "number_string(N, '3.14') -> N=3.14"
+  (pl-num-val (pl-walk-deep (dict-get pl-mp-env-ns2 "N")))
+  3.14)
+
+(define pl-meta-predicates-tests-run! (fn () {:failed pl-mp-test-fail :passed pl-mp-test-pass :total pl-mp-test-count :failures pl-mp-test-failures}))

lib/prolog/tests/operators.sx

@@ -0,0 +1,193 @@
+;; lib/prolog/tests/operators.sx — operator-table parsing + comparison built-ins.
+
+(define pl-op-test-count 0)
+(define pl-op-test-pass 0)
+(define pl-op-test-fail 0)
+(define pl-op-test-failures (list))
+
+(define
+  pl-op-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-op-test-count (+ pl-op-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-op-test-pass (+ pl-op-test-pass 1))
+        (begin
+          (set! pl-op-test-fail (+ pl-op-test-fail 1))
+          (append!
+            pl-op-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define pl-op-empty-db (pl-mk-db))
+
+(define
+  pl-op-body
+  (fn (src) (nth (first (pl-parse (str "g :- " src "."))) 2)))
+
+(define pl-op-goal (fn (src env) (pl-instantiate (pl-op-body src) env)))
+
+;; ── parsing tests ──
+
+(pl-op-test!
+  "infix +"
+  (pl-op-body "a + b")
+  (list "compound" "+" (list (list "atom" "a") (list "atom" "b"))))
+
+(pl-op-test!
+  "infix * tighter than +"
+  (pl-op-body "a + b * c")
+  (list
+    "compound"
+    "+"
+    (list
+      (list "atom" "a")
+      (list "compound" "*" (list (list "atom" "b") (list "atom" "c"))))))
+
+(pl-op-test!
+  "parens override precedence"
+  (pl-op-body "(a + b) * c")
+  (list
+    "compound"
+    "*"
+    (list
+      (list "compound" "+" (list (list "atom" "a") (list "atom" "b")))
+      (list "atom" "c"))))
+
+(pl-op-test!
+  "+ is yfx (left-assoc)"
+  (pl-op-body "a + b + c")
+  (list
+    "compound"
+    "+"
+    (list
+      (list "compound" "+" (list (list "atom" "a") (list "atom" "b")))
+      (list "atom" "c"))))
+
+(pl-op-test!
+  "; is xfy (right-assoc)"
+  (pl-op-body "a ; b ; c")
+  (list
+    "compound"
+    ";"
+    (list
+      (list "atom" "a")
+      (list "compound" ";" (list (list "atom" "b") (list "atom" "c"))))))
+
+(pl-op-test!
+  "= folds at 700"
+  (pl-op-body "X = 5")
+  (list "compound" "=" (list (list "var" "X") (list "num" 5))))
+
+(pl-op-test!
+  "is + nests via 700>500>400"
+  (pl-op-body "X is 2 + 3 * 4")
+  (list
+    "compound"
+    "is"
+    (list
+      (list "var" "X")
+      (list
+        "compound"
+        "+"
+        (list
+          (list "num" 2)
+          (list "compound" "*" (list (list "num" 3) (list "num" 4))))))))
+
+(pl-op-test!
+  "< parses at 700"
+  (pl-op-body "2 < 3")
+  (list "compound" "<" (list (list "num" 2) (list "num" 3))))
+
+(pl-op-test!
+  "mod parses as yfx 400"
+  (pl-op-body "10 mod 3")
+  (list "compound" "mod" (list (list "num" 10) (list "num" 3))))
+
+(pl-op-test!
+  "comma in body folds right-assoc"
+  (pl-op-body "a, b, c")
+  (list
+    "compound"
+    ","
+    (list
+      (list "atom" "a")
+      (list "compound" "," (list (list "atom" "b") (list "atom" "c"))))))
+
+;; ── solver tests via infix ──
+
+(pl-op-test!
+  "X is 2 + 3 binds X = 5"
+  (let
+    ((env {}) (trail (pl-mk-trail)))
+    (begin
+      (pl-solve-once! pl-op-empty-db (pl-op-goal "X is 2 + 3" env) trail)
+      (pl-num-val (pl-walk-deep (dict-get env "X")))))
+  5)
+
+(pl-op-test!
+  "infix conjunction parses + solves"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "X = 5, X = 5" {})
+    (pl-mk-trail))
+  true)
+
+(pl-op-test!
+  "infix mismatch fails"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "X = 5, X = 6" {})
+    (pl-mk-trail))
+  false)
+
+(pl-op-test!
+  "infix disjunction picks left"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "true ; fail" {})
+    (pl-mk-trail))
+  true)
+
+(pl-op-test!
+  "2 < 5 succeeds"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "2 < 5" {})
+    (pl-mk-trail))
+  true)
+
+(pl-op-test!
+  "5 < 2 fails"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "5 < 2" {})
+    (pl-mk-trail))
+  false)
+
+(pl-op-test!
+  "5 >= 5 succeeds"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "5 >= 5" {})
+    (pl-mk-trail))
+  true)
+
+(pl-op-test!
+  "3 =< 5 succeeds"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "3 =< 5" {})
+    (pl-mk-trail))
+  true)
+
+(pl-op-test!
+  "infix < with arithmetic both sides"
+  (pl-solve-once!
+    pl-op-empty-db
+    (pl-op-goal "1 + 2 < 2 * 3" {})
+    (pl-mk-trail))
+  true)
+
+(define pl-operators-tests-run! (fn () {:failed pl-op-test-fail :passed pl-op-test-pass :total pl-op-test-count :failures pl-op-test-failures}))

lib/prolog/tests/programs/append.pl

@@ -0,0 +1,5 @@
+%% append/3 — list concatenation, classic Prolog
+%% Two clauses: empty-prefix base case + recursive cons-prefix.
+%% Bidirectional — works in all modes: build, check, split.
+append([], L, L).
+append([H|T], L, [H|R]) :- append(T, L, R).

lib/prolog/tests/programs/append.sx

@@ -0,0 +1,114 @@
+;; lib/prolog/tests/programs/append.sx — append/3 test runner
+;;
+;; Mirrors the Prolog source in append.pl (embedded as a string here because
+;; the SX runtime has no file-read primitive yet).
+
+(define pl-ap-test-count 0)
+(define pl-ap-test-pass 0)
+(define pl-ap-test-fail 0)
+(define pl-ap-test-failures (list))
+
+(define
+  pl-ap-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! pl-ap-test-count (+ pl-ap-test-count 1))
+      (if
+        (= got expected)
+        (set! pl-ap-test-pass (+ pl-ap-test-pass 1))
+        (begin
+          (set! pl-ap-test-fail (+ pl-ap-test-fail 1))
+          (append!
+            pl-ap-test-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+(define
+  pl-ap-term-to-sx
+  (fn
+    (t)
+    (cond
+      ((pl-num? t) (pl-num-val t))
+      ((pl-atom? t) (pl-atom-name t))
+      (true (list :complex)))))
+
+(define
+  pl-ap-list-walked
+  (fn
+    (w)
+    (cond
+      ((and (pl-atom? w) (= (pl-atom-name w) "[]")) (list))
+      ((and (pl-compound? w) (= (pl-fun w) ".") (= (len (pl-args w)) 2))
+        (cons
+          (pl-ap-term-to-sx (first (pl-args w)))
+          (pl-ap-list-walked (nth (pl-args w) 1))))
+      (true (list :not-list)))))
+
+(define pl-ap-list-to-sx (fn (t) (pl-ap-list-walked (pl-walk-deep t))))
+
+(define
+  pl-ap-goal
+  (fn
+    (src env)
+    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))
+
+(define
+  pl-ap-prog-src
+  "append([], L, L). append([H|T], L, [H|R]) :- append(T, L, R).")
+
+(define pl-ap-db (pl-mk-db))
+
+(pl-db-load! pl-ap-db (pl-parse pl-ap-prog-src))
+
+(define pl-ap-env-1 {})
+(define pl-ap-goal-1 (pl-ap-goal "append([], [a, b], X)" pl-ap-env-1))
+(pl-solve-once! pl-ap-db pl-ap-goal-1 (pl-mk-trail))
+
+(pl-ap-test!
+  "append([], [a, b], X) → X = [a, b]"
+  (pl-ap-list-to-sx (dict-get pl-ap-env-1 "X"))
+  (list "a" "b"))
+
+(define pl-ap-env-2 {})
+(define pl-ap-goal-2 (pl-ap-goal "append([1, 2], [3, 4], X)" pl-ap-env-2))
+(pl-solve-once! pl-ap-db pl-ap-goal-2 (pl-mk-trail))
+
+(pl-ap-test!
+  "append([1, 2], [3, 4], X) → X = [1, 2, 3, 4]"
+  (pl-ap-list-to-sx (dict-get pl-ap-env-2 "X"))
+  (list 1 2 3 4))
+
+(pl-ap-test!
+  "append([1], [2, 3], [1, 2, 3]) succeeds"
+  (pl-solve-once!
+    pl-ap-db
+    (pl-ap-goal "append([1], [2, 3], [1, 2, 3])" {})
+    (pl-mk-trail))
+  true)
+
+(pl-ap-test!
+  "append([1, 2], [3], [1, 2, 4]) fails"
+  (pl-solve-once!
+    pl-ap-db
+    (pl-ap-goal "append([1, 2], [3], [1, 2, 4])" {})
+    (pl-mk-trail))
+  false)
+
+(pl-ap-test!
+  "append(X, Y, [1, 2, 3]) backtracks 4 times"
+  (pl-solve-count!
+    pl-ap-db
+    (pl-ap-goal "append(X, Y, [1, 2, 3])" {})
+    (pl-mk-trail))
+  4)
+
+(define pl-ap-env-6 {})
+(define pl-ap-goal-6 (pl-ap-goal "append(X, [3], [1, 2, 3])" pl-ap-env-6))
+(pl-solve-once! pl-ap-db pl-ap-goal-6 (pl-mk-trail))
+
+(pl-ap-test!
+  "append(X, [3], [1, 2, 3]) deduces X = [1, 2]"
+  (pl-ap-list-to-sx (dict-get pl-ap-env-6 "X"))
+  (list 1 2))
+
+(define pl-append-tests-run! (fn () {:failed pl-ap-test-fail :passed pl-ap-test-pass :total pl-ap-test-count :failures pl-ap-test-failures}))

lib/prolog/tests/programs/family.pl

@@ -0,0 +1,24 @@
+%% family — facts + transitive ancestor + derived relations.
+%% Five-generation tree: tom -> bob -> {ann, pat} -> jim, plus tom's
+%% other child liz.
+
+parent(tom, bob).
+parent(tom, liz).
+parent(bob, ann).
+parent(bob, pat).
+parent(pat, jim).
+
+male(tom).
+male(bob).
+male(jim).
+male(pat).
+female(liz).
+female(ann).
+
+father(F, C) :- parent(F, C), male(F).
+mother(M, C) :- parent(M, C), female(M).
+
+ancestor(X, Y) :- parent(X, Y).
+ancestor(X, Y) :- parent(X, Z), ancestor(Z, Y).
+
+sibling(X, Y) :- parent(P, X), parent(P, Y), \=(X, Y).