Closure is not a pair.

* module/mes/base.mes (closure_p, mes_car, mes_cdr): New function.
  (pair_p): Closure is not a pair.
* NEWS: Mention it.
* psyntax-0.mes (self-evaluating?): Add closure?.

NEWS

@@ -22,6 +22,8 @@ block-comments are all handled by the Scheme reader later.
 *** Lambda* and define* are now supported.
 *** #;-comment is now supported.
 *** Non-nested #| |#-comment is now supported.
+** Noteworthy bug fixes
+*** Closure is not a pair.
 * Changes in 0.3 since 0.2
 ** Core
 *** Number-based rather than pointer-based cells.

module/mes/base.mes

@@ -59,5 +59,5 @@
 (define (procedure? p)
   (cond ((builtin? p) #t)
         ((and (pair? p) (eq? (car p) 'lambda)))
-        ((and (pair? p) (eq? (car p) '*closure*)))
+        ((closure? p) #t)
         (#t #f)))

module/mes/psyntax-0.mes

@@ -33,7 +33,7 @@
 
 (define annotation? (lambda (x) #f))
 (define (self-evaluating? x)
-  (or (boolean? x) (number? x) (string? x) (char? x) (null? x)))
+  (or (boolean? x) (number? x) (string? x) (char? x) (null? x) (closure? x)))
 
 (define (void) (if #f #f))
 

tests/closure.test

@@ -95,4 +95,10 @@ exit $?
     "noexpand")
    (pass-if "closure 9" (sc-expand))))
 
+(pass-if "closure is procedure"
+             (procedure? (lambda () #t)))
+
+(pass-if-not "closure is not a pair"
+             (pair? (lambda () #t)))
+
 (result 'report)

type.c

@@ -26,6 +26,24 @@ char_p (SCM x)
   return TYPE (x) == CHAR ? cell_t : cell_f;
 }
 
+SCM
+closure_p (SCM x)
+{
+  return (TYPE (x) == PAIR && CAR (x) == cell_closure) ? cell_t : cell_f;
+}
+
+SCM
+mes_car (SCM x)
+{
+  return CAR (x);
+}
+
+SCM
+mes_cdr (SCM x)
+{
+  return CDR (x);
+}
+
 SCM
 keyword_p (SCM x)
 {
@@ -47,7 +65,7 @@ number_p (SCM x)
 SCM
 pair_p (SCM x)
 {
-  return TYPE (x) == PAIR ? cell_t : cell_f;
+  return (TYPE (x) == PAIR && CAR (x) != cell_closure) ? cell_t : cell_f;
 }
 
 SCM