kernel: reader macros + 8 tests (Phase 1 closure) [consumes-lex]

Parser now reads 'expr, \`expr, ,expr, ,@expr as the four standard
shorthands. Quote uses existing $quote operative; quasiquote /
unquote / unquote-splicing recognised but not yet expanded at runtime
(left for first consumer to drive). 218 tests total across six suites.

lib/kernel/parser.sx

@@ -37,7 +37,10 @@
       (= c "(")
       (= c ")")
       (= c "\"")
-      (= c ";"))))
+      (= c ";")
+      (= c "'")
+      (= c "`")
+      (= c ","))))
 
 ;; Numeric grammar:  [+-]? (digit+ ('.' digit+)? | '.' digit+) ([eE][+-]?digit+)?
 (define
@@ -199,6 +202,16 @@
             ((= (at) "(") (do (adv) (read-list (list))))
             ((= (at) "\"")
               (do (adv) (kernel-string-make (read-string-body ""))))
+            ((= (at) "'")
+              (do (adv) (list "$quote" (read-form))))
+            ((= (at) "`")
+              (do (adv) (list "$quasiquote" (read-form))))
+            ((= (at) ",")
+              (do (adv)
+                  (cond
+                    ((= (at) "@")
+                      (do (adv) (list "$unquote-splicing" (read-form))))
+                    (:else (list "$unquote" (read-form))))))
             (:else (classify-atom (read-atom-body ""))))))
       (define
         read-list

lib/kernel/tests/parse.sx

@@ -131,4 +131,28 @@
 (knl-test "identity: wrap" (kernel-parse "wrap") "wrap")
 (knl-test "identity: unwrap" (kernel-parse "unwrap") "unwrap")
 
+;; ── reader macros ─────────────────────────────────────────────────
+(knl-test "reader: 'foo  → ($quote foo)"
+  (kernel-parse "'foo") (list "$quote" "foo"))
+(knl-test "reader: '(a b c)"
+  (kernel-parse "'(a b c)") (list "$quote" (list "a" "b" "c")))
+(knl-test "reader: nested quotes"
+  (kernel-parse "''x")
+  (list "$quote" (list "$quote" "x")))
+(knl-test "reader: ` quasiquote"
+  (kernel-parse "`x") (list "$quasiquote" "x"))
+(knl-test "reader: , unquote"
+  (kernel-parse ",x") (list "$unquote" "x"))
+(knl-test "reader: ,@ unquote-splicing"
+  (kernel-parse ",@x") (list "$unquote-splicing" "x"))
+(knl-test "reader: quasi-mix"
+  (kernel-parse "`(a ,b ,@c)")
+  (list "$quasiquote"
+        (list "a"
+              (list "$unquote" "b")
+              (list "$unquote-splicing" "c"))))
+(knl-test "reader: quote separates from neighbouring atom"
+  (kernel-parse "(a 'b c)")
+  (list "a" (list "$quote" "b") "c"))
+
 (define knl-tests-run! (fn () {:total (+ knl-test-pass knl-test-fail) :passed knl-test-pass :failed knl-test-fail :fails knl-test-fails}))