[cl-json-devel] patch to improve encode-json for lists

[Nathan Hawkins]

This fairly simple patch seems to enable encode-json to handle alists.

After applying:

;; handles alists
(defvar *foo* '((a . 1) (b . 2) (c . 3)))
(encode-json-to-string *foo*)
--> "{\"a\":1,\"b\":2,\"c\":3}"

;; normal lists still work
(defvar *bar* '(1 2 3 4 5))
(encode-json-to-string *bar*)
--> "[1,2,3,4,5]"

;; messed up lists of alists which contain lists also works now
(defvar *baz* '(((a . 1) (b .2) (c . 3) (d . (1 2 3 4 5)))))
(encode-json-to-string *baz*)
--> "[{\"a\":1,\"b\":[0.2],\"c\":3,\"d\":[1,2,3,4,5]}]"

;; even better, decode-json likes the output
(decode-json-from-string "[{\"a\":1,\"b\":[0.2
],\"c\":3,\"d\":[1,2,3,4,5]}]")
--> (((:A . 1) (:B 0.2) (:C . 3) (:D 1 2 3 4 5)))

One thing you can't do is encode a list appended to an alist. That won't
work, and I don't know how you'd
encode it in JSON anyway.

Someone who's had way more sleep than I have lately should test this as
well. But I can now both encode
and decode lists of alists, which scratches my particular itch...

Nathan

diff -rN -u old-cl-json/src/encoder.lisp new-cl-json/src/encoder.lisp
--- old-cl-json/src/encoder.lisp    2007-03-21 23:29:22.000000000 -0400
+++ new-cl-json/src/encoder.lisp    2007-03-21 23:29:22.000000000 -0400
@@ -25,6 +25,12 @@
     (t (write-json-string (funcall *symbol-to-string-fn* s) stream))))

 (defmethod encode-json((s sequence ) stream)
+  (if (and (consp (car s))
+           (atom (cdar s)))
+    (encode-json-alist s stream)
+    (encode-json-list s stream)))
+
+(defun encode-json-list (s stream)
   (let ((first-element t))
     (write-char #\[ stream)
     (map nil #'(lambda (element)
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