21.4.21 and font-lock-add-keywords

[John Kuhns]

Jerry -

Thanks for your patch and syntax fix. I tested it and it is working for me.

-John

Jerry James wrote:
> Hi John,
>
> On Jan 7, 2008 8:56 AM, John Kuhns <john at designadvance.com> wrote:
>   
>> Hi XEmacs team -
>>
>> So I installed xemacs 21.4.21 today and tried out the new
>> font-lock-add-keywords method. But, for some reason it's still not
>> working for me. Is there something I need to set to get it working?
>>
>> Here's what I tried:
>> (add-hook 'lisp-mode-hook
>> (lambda () (font-lock-add-keywords 'lisp-mode
>> '(("\\<\\(then\\|else\\|@key\\|@optional\\)\\>" .
>> font-lock-keyword-face)))))
>>
>> Which I want to result in highlighting standalone keywords. For example,
>> @key should be hightlighted in this line:
>> (defun foo (arg1 @key arg2) ... )
>>     
>
> It looks like you are the victim of an incomplete sync with Emacs.
> The code to use the values passed to font-lock-add-keywords was never
> put into XEmacs.  In short, font-lock-add-keywords does not do
> anything useful in any released version of XEmacs.
>
> If you can compile your own XEmacs, try the patch below, which fixes
> the problem for me.  Also, you should change your code above in one of
> two ways. First, use add-one-shot-hook instead of add-hook, or you'll
> keep adding the same expression to the font-lock keywords for Lisp
> every time you open a Lisp file.  Second, don't use a hook at all:
> just make the (font-lock-add-keywords ...) call in your
> .xemacs/init.el file.
>
> Finally, it appears that "\\<@" doesn't match " @".  I don't know why
> (probably something to do with @ not being a word character), or
> whether that is correct, but a workaround is to change your regexp
> like this:
>
> (font-lock-add-keywords 'lisp-mode
> 			'(("\\(\\<then\\|\\<else\\|@key\\|@optional\\)\\>" .
> 			   font-lock-keyword-face)))
>
> diff -r e8f448f997ac lisp/font-lock.el
> --- a/lisp/font-lock.el	Mon Jan 14 15:25:22 2008 +0100
> +++ b/lisp/font-lock.el	Mon Jan 14 12:55:39 2008 -0700
> @@ -959,7 +959,7 @@ see the variables `c-font-lock-extra-typ
>  	 (let ((was-compiled (eq (car font-lock-keywords) t)))
>  	   ;; Bring back the user-level (uncompiled) keywords.
>  	   (if was-compiled
> -	       (setq font-lock-keywords (cadr font-lock-keywords)))
> +	       (setq font-lock-keywords (cdr font-lock-keywords)))
>  	   ;; Now modify or replace them.
>  	   (if (eq how 'set)
>  	       (setq font-lock-keywords keywords)
> @@ -1069,7 +1069,7 @@ happens, so the major mode can be correc
>  	 (let ((was-compiled (eq (car font-lock-keywords) t)))
>  	   ;; Bring back the user-level (uncompiled) keywords.
>  	   (if was-compiled
> -	       (setq font-lock-keywords (cadr font-lock-keywords)))
> +	       (setq font-lock-keywords (cdr font-lock-keywords)))
>
>  	   ;; Edit them.
>  	   (setq font-lock-keywords (copy-sequence font-lock-keywords))
> @@ -2031,7 +2031,10 @@ Each keyword has the form (MATCHER HIGHL
>  			     font-lock-defaults
>  			     (font-lock-find-font-lock-defaults major-mode)))
>  	       (keywords (font-lock-choose-keywords
> -			  (nth 0 defaults) font-lock-maximum-decoration)))
> +			  (nth 0 defaults) font-lock-maximum-decoration))
> +	       (local (cdr (assq major-mode font-lock-keywords-alist)))
> +	       (removed-keywords
> +		(cdr-safe (assq major-mode font-lock-removed-keywords-alist))))
>
>  	  ;; Keywords?
>  	  (setq font-lock-keywords (if (fboundp keywords)
> @@ -2096,7 +2099,14 @@ Each keyword has the form (MATCHER HIGHL
>  		 ;; older way:
>  		 ;; defaults not specified at all, so use `beginning-of-defun'.
>  		 (setq font-lock-beginning-of-syntax-function
> -		       'beginning-of-defun)))))
> +		       'beginning-of-defun)))
> +
> +	  ;; Local fontification?
> +	  (while local
> +	    (font-lock-add-keywords nil (car (car local)) (cdr (car local)))
> +	    (setq local (cdr local)))
> +	  (when removed-keywords
> +	    (font-lock-remove-keywords nil removed-keywords))))
>
>      (setq font-lock-cache-position (make-marker))
>      (setq font-lock-defaults-computed t)))
>
>