tcl: Phase 1 parser — word-simple? + word-literal helpers (+15 tests, 67 total)

lib/tcl/parser.sx

@@ -0,0 +1,41 @@
+; Tcl parser — thin layer over tcl-tokenize
+; Adds tcl-parse entry point and word utility fns
+
+; Entry point: parse Tcl source to a list of commands.
+; Returns same structure as tcl-tokenize.
+(define tcl-parse (fn (src) (tcl-tokenize src)))
+
+; True if word has no substitutions — value can be read statically.
+; braced words are always simple. compound words are simple when all
+; parts are plain text with no var/cmd parts.
+(define tcl-word-simple?
+  (fn (word)
+    (cond
+      ((= (get word :type) "braced") true)
+      ((= (get word :type) "compound")
+        (let ((parts (get word :parts)))
+          (every? (fn (p) (= (get p :type) "text")) parts)))
+      (else false))))
+
+; Concatenate text parts of a simple word into a single string.
+; For braced words returns :value directly.
+; For compound words with only text parts, joins them.
+; Returns nil for words with substitutions.
+(define tcl-word-literal
+  (fn (word)
+    (cond
+      ((= (get word :type) "braced") (get word :value))
+      ((= (get word :type) "compound")
+        (if (tcl-word-simple? word)
+          (join "" (map (fn (p) (get p :value)) (get word :parts)))
+          nil))
+      (else nil))))
+
+; Number of words in a parsed command.
+(define tcl-cmd-len
+  (fn (cmd) (len (get cmd :words))))
+
+; Nth word literal from a command (index 0 = command name).
+; Returns nil if word has substitutions.
+(define tcl-nth-literal
+  (fn (cmd n) (tcl-word-literal (nth (get cmd :words) n))))

lib/tcl/test.sh

@@ -17,8 +17,10 @@ cat > "$TMPFILE" << 'EPOCHS'
 (epoch 1)
 (load "lib/tcl/tokenizer.sx")
 (epoch 2)
-(load "lib/tcl/tests/parse.sx")
+(load "lib/tcl/parser.sx")
 (epoch 3)
+(load "lib/tcl/tests/parse.sx")
+(epoch 4)
 (eval "(tcl-run-parse-tests)")
 EPOCHS
 
@@ -26,12 +28,12 @@ OUTPUT=$(timeout 30 "$SX_SERVER" < "$TMPFILE" 2>&1)
 [ "$VERBOSE" = "-v" ] && echo "$OUTPUT"
 
 # Result follows an (ok-len 3 N) line
-RESULT=$(echo "$OUTPUT" | grep -A1 "^(ok-len 3 " | tail -1)
+RESULT=$(echo "$OUTPUT" | grep -A1 "^(ok-len 4 " | tail -1)
 if [ -z "$RESULT" ]; then
-  RESULT=$(echo "$OUTPUT" | grep "^(ok 3 " | sed 's/^(ok 3 //' | sed 's/)$//')
+  RESULT=$(echo "$OUTPUT" | grep "^(ok 4 " | sed 's/^(ok 3 //' | sed 's/)$//')
 fi
 if [ -z "$RESULT" ]; then
-  echo "ERROR: no result from epoch 3"
+  echo "ERROR: no result from epoch 4"
   echo "$OUTPUT" | tail -10
   exit 1
 fi

lib/tcl/tests/parse.sx

@@ -129,6 +129,57 @@
     (tcl-assert "cont-word2-val" "1"
       (get (tcl-part "set x \\\n  1" 2 0) :value))
 
+
+    ; --- parser helpers ---
+    ; tcl-parse is an alias for tcl-tokenize
+    (tcl-assert "parse-cmd-count" 1 (len (tcl-parse "set x 1")))
+    (tcl-assert "parse-2cmds" 2 (len (tcl-parse "set x 1; set y 2")))
+
+    ; tcl-cmd-len
+    (tcl-assert "cmd-len-3" 3 (tcl-cmd-len (nth (tcl-parse "set x 1") 0)))
+    (tcl-assert "cmd-len-1" 1 (tcl-cmd-len (nth (tcl-parse "puts") 0)))
+
+    ; tcl-word-simple? on braced word
+    (tcl-assert "simple-braced" true
+      (tcl-word-simple? (nth (get (nth (tcl-parse "{hello}") 0) :words) 0)))
+
+    ; tcl-word-simple? on bare word with no subs
+    (tcl-assert "simple-bare" true
+      (tcl-word-simple? (nth (get (nth (tcl-parse "hello") 0) :words) 0)))
+
+    ; tcl-word-simple? on word containing a var sub — false
+    (tcl-assert "simple-var-false" false
+      (tcl-word-simple? (nth (get (nth (tcl-parse "$x") 0) :words) 0)))
+
+    ; tcl-word-simple? on word containing a cmd sub — false
+    (tcl-assert "simple-cmd-false" false
+      (tcl-word-simple? (nth (get (nth (tcl-parse "[expr 1]") 0) :words) 0)))
+
+    ; tcl-word-literal on braced word
+    (tcl-assert "lit-braced" "hello world"
+      (tcl-word-literal (nth (get (nth (tcl-parse "{hello world}") 0) :words) 0)))
+
+    ; tcl-word-literal on bare word
+    (tcl-assert "lit-bare" "hello"
+      (tcl-word-literal (nth (get (nth (tcl-parse "hello") 0) :words) 0)))
+
+    ; tcl-word-literal on word with var sub returns nil
+    (tcl-assert "lit-var-nil" nil
+      (tcl-word-literal (nth (get (nth (tcl-parse "$x") 0) :words) 0)))
+
+    ; tcl-nth-literal
+    (tcl-assert "nth-lit-0" "set"
+      (tcl-nth-literal (nth (tcl-parse "set x 1") 0) 0))
+    (tcl-assert "nth-lit-1" "x"
+      (tcl-nth-literal (nth (tcl-parse "set x 1") 0) 1))
+    (tcl-assert "nth-lit-2" "1"
+      (tcl-nth-literal (nth (tcl-parse "set x 1") 0) 2))
+
+    ; tcl-nth-literal returns nil when word has subs
+    (tcl-assert "nth-lit-nil" nil
+      (tcl-nth-literal (nth (tcl-parse "set x $y") 0) 2))
+
+
     (dict
       "passed" tcl-parse-pass
       "failed" tcl-parse-fail