Re: What is this syntax for in php-mode.el

[Stefan Monnier]

> I am looking at php-mode.el from Turadg. I can not understand this:

> (defconst php-font-lock-syntactic-keywords
>   (if xemacsp nil
>     ;; Mark shell-style comments.  font-lock handles this in a
>     ;; separate pass from normal syntactic scanning (somehow), so we
>     ;; get a chance to mark these in addition to C and C++ style
>     ;; comments.  This only works in GNU Emacs, not XEmacs 21 which
>     ;; seems to ignore this same code if we try to use it.
>     (list
>      ;; Mark _all_ # chars as being comment-start.  That will be
>      ;; ignored when inside a quoted string.
>      '("\\(\#\\)"
>        (1 (11 . nil)))
>      ;; Mark all newlines ending a line with # as being comment-end.
>      ;; This causes a problem, premature end-of-comment, when '#'
>      ;; appears inside a multiline C-style comment.  Oh well.
>      '("#.*\\([\n]\\)"
>        (1 (12 . nil)))
>      )))

> What is it for? Does php use # as a comment somewhere?

> And what about the format for the list entries? I tried to look at
> font-lock-syntactic-keywords, but I can not see that these entries follows
> the spec there.

> How does this work?

Please tell the author that he doesn't need this gymnastics.
Just set # to comment-starter in the syntax-table and be done with it.
Make sure it has the comment-style (a or b) corresponding to the one of \n
(presumably it's b, if I read the problem-comment above correctly):

    (modify-syntax-entry ?# "< b" php-mode-syntax-table)


-- Stefan