[suave-devel] Re: js-to-paren for loop bug

[Lui Fungsin]

I also notice that parenscript will read (= x 3) as (== x 3). We
probably need to translate = to setf

Here's a patch

==== js-on-cl/src/js-to-parenscript.lisp ====
@@ -1,5 +1,30 @@
 (in-package :js-on-cl)

+(defparameter *symbols-to-paren-tokens*
+  (let ((ht (make-hash-table :test 'eq)))
+    (maphash #'(lambda (k v)
+                (setf (gethash k ht) v))
+             *symbols-to-tokens*)
+    (loop for (k v) in '(;; where do these appears?
+                         ;;(:COLON ":")
+                         ;;(:HOOK "?")
+                         (:LOGICAL-OR "or")
+                         (:ASSIGN "setf")
+                         (:BAR2 "or")
+                         (:BANG "not")
+                         (:POST-INCR "incf")
+                         (:MINUS2 "decf")
+                         (:POST-DECR "decf")
+                         (:PLUS2 "incf")
+                         (:PRE-INCR "incf")
+                         (:PRE-DECR "decf")
+                         (:LOGICAL-NOT "not"))
+          do (setf (gethash k ht) v))
+    ht)
+  "Map from token symbol to parenscript token.")
+
+
+
 (defun js-intern (js-literal-string)
   "interns a camel-cased js string to an appropriate lispy symbol"
   (intern
@@ -56,7 +81,7 @@
 (defun token-to-paren (tok)
   (js-intern
    (or
-    (gethash tok *symbols-to-tokens*)
+    (gethash tok *symbols-to-paren-tokens*)
     (string-downcase (string tok)))))

 (defmethod as-paren ((js-form unary-operator))
@@ -143,11 +168,10 @@
 	(condition (for-condition js-form))
 	(step (for-step js-form))
 	(body (for-body js-form)) )
-    `(while t
+    `(progn
       ,(as-paren initializer)
-      (if (not ,(as-paren condition))
-	  (break))
-      ,(as-paren step) ,(as-paren body))))
+      (while ,(as-paren condition)
+        ,(as-paren body) ,(as-paren step)))))


 (defmethod as-paren ((js-form comma-expr))
==== end patch ====


Another problem is that the pre/post increment operation needs to be
handled differently. Currently

(js-to-paren "while (i++ > 3) { --j }")
=>
(PROGN (WHILE (> (INCF I) 3) (PROGN (DECF J))))

But it's incorrect.

It should probably be something like
(PROGN (WHILE (> I 3) (PROGN (INCF I) (DECF J))))

But I don't know how to make it right, since the translation is done
in a bottom-up style.

Thanks