trivial addition of NaN

[jetmonk]

NaNs are not supported in JSON by default (though in Perl parser apparently). Some JSON files contain them, though.

I found this to be a useful change in parse.lisp

;; export *allow-nan* and 'nan symbols in package.lisp
(defvar *allow-nan* t) 
		    
(defun parse-constant (input)
  (let ((buffer (make-adjustable-string)))
    (loop while (alpha-char-p (peek-char nil input))
          do (vector-push-extend (read-char input) buffer))
    (cond ((string= buffer "true")
	   (if *parse-json-booleans-as-symbols* 'true t))
	  ((string= buffer "false")
	   (if *parse-json-booleans-as-symbols* 'false nil))
	  ((string= buffer "null")
	   (if *parse-json-booleans-as-symbols* 'null  nil))
	  ((and *allow-nan* (string-equal buffer "nan")) ;; allow NaN, nan, etc
	   'nan)
	  (t
	   (error "invalid constant '~A'" buffer)))))

In a followup, I appended updated version that does NaN,nan,inf,infinity,+infinity,-infinity (case insensitive). In parse-number it switches to parse-symbol if it encounters a +/- followed by 'i' or 'I' (for infinity)

Also, the original yason didn't allow a number to have a leading plus sign like {x: +99} because parse% checked only for a leading (#- #\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9). This is correct according to JSON standard, but the new version loosens this restriction to allow parsing of slightly non-compliant JSON.

parse.lisp.txt

[phmarek]

Would you please create a pull-request here? Thanks a lot!

[jetmonk]

I think I sent a pull request from repository below, but I've never done this before, so have no idea if I did it right.

My modified version is: https://github.com/jetmonk/yason/tree/jetmonk-patch-1

[phmarek]

I think I did this, but I've never done this before. My modified version is: https://github.com/jetmonk/yason/tree/jetmonk-patch-1

Hmmm.... looking at the change I'm not really sure how you would achieve this, but it looks like you're reverting all my latest changes? master...jetmonk:jetmonk-patch-1 My only guess is that you did the changes against the old version and then told git to reset the git HEAD pointer to the (then newer) git HEAD without doing a merge or rebase?!

[jetmonk]

Sorry. 2nd pull request submitted. Hope this one is OK.