[AUCTeX-devel] Fun with syntax tables

[Ralf Angeli]

Suppose you have line like
foo \verb|bar| baz
in a LaTeX buffer.  font-latex puts syntax properties (string quote
syntax) onto the | characters which then get picked up by
`font-lock-fontify-syntactically-region'.  This happens with help of
`parse-partial-sexp'.

This is fine in LaTeX mode, but fails in documentation parts of docTeX
mode.  There the line would look like this:
% foo \verb|bar| baz
That means with a comment starter at the front.

The problem is that with % as the comment start and \n as the comment
end `parse-partial-sexp' won't find the stuff marked with string quote
syntax inside of the comment.  Here is an example:

(with-temp-buffer
  (let ((my-syntax-table (make-syntax-table)))
    (modify-syntax-entry ?% "<" my-syntax-table)
    (modify-syntax-entry ?\n ">" my-syntax-table)
    (with-syntax-table my-syntax-table
      (insert "%foo |X| bar")
      (goto-char (point-min))
      (search-forward "|")
      (put-text-property (1- (point)) (point) 'syntax-table '(7))
      (search-forward "|")
      (put-text-property (1- (point)) (point) 'syntax-table '(7))
      (goto-char (point-min))
      (set (make-local-variable 'parse-sexp-lookup-properties) t)
      (let ((old-state (parse-partial-sexp (point-min) (point-max)
                                           nil nil nil 'syntax-table)))
        (parse-partial-sexp (point) (point-max)
                            nil nil old-state 'syntax-table))
      (point))))

If you execute it, it should return 13 which is the end of the line.
If you remove the % character from the inserted string it will return
8 which is the position just after the second | character.

Can anybody tell me how to make the string quote stuff visible for
`parse-partial-sexp'?

-- 
Ralf