+2015-03-22 Dmitry Gutov <dgutov@yandex.ru>
+
+ * json.el (json-decode-char0): Delete this alias.
+ (json-encode-string): Rewrite to improve performance (bug#20154).
+ (json-encode-char): Fold into `json-encode-string'.
+
2015-03-22 Artur Malabarba <bruce.connor.am@gmail.com>
* menu-bar.el (menu-bar-update-buffers): Count displayed buffers
;; Compatibility code
-(defalias 'json-encode-char0 'encode-char)
(defalias 'json-decode-char0 'decode-char)
;; String encoding
-(defun json-encode-char (char)
- "Encode CHAR as a JSON string."
- (setq char (json-encode-char0 char 'ucs))
- (let ((control-char (car (rassoc char json-special-chars))))
- (cond
- ;; Special JSON character (\n, \r, etc.).
- (control-char
- (format "\\%c" control-char))
- ;; ASCIIish printable character.
- ((and (> char 31) (< char 127))
- (format "%c" char))
- ;; Fallback: UCS code point in \uNNNN form.
- (t
- (format "\\u%04x" char)))))
-
(defun json-encode-string (string)
"Return a JSON representation of STRING."
- (format "\"%s\"" (mapconcat 'json-encode-char string "")))
+ ;; Reimplement the meat of `replace-regexp-in-string', for
+ ;; performance (bug#20154).
+ (let ((l (length string))
+ (start 0)
+ res mb)
+ ;; Skip over ASCIIish printable characters.
+ (while (setq mb (string-match "[\"\\/\b\f\n\r\t]\\|[^ -~]" string start))
+ (let* ((c (aref string mb))
+ (special (rassq c json-special-chars)))
+ (push (substring string start mb) res)
+ (push (if special
+ ;; Special JSON character (\n, \r, etc.).
+ (string ?\\ (car special))
+ ;; Fallback: UCS code point in \uNNNN form.
+ (format "\\u%04x" c))
+ res)
+ (setq start (1+ mb))))
+ (push (substring string start l) res)
+ (push "\"" res)
+ (apply #'concat "\"" (nreverse res))))
(defun json-encode-key (object)
"Return a JSON representation of OBJECT.