Re: web-mode.el

[Stefan Monnier <monnier@IRO.UMontreal.CA>]

>>> 2) sgml-indent-line calls sgml-parse-tag-backward, which does
>>> (re-search-backward "[<>]"), finds "<" and performs simple regexp check.
>>> Thus,<% if a<  3 %>  breaks indentation on following lines, until first
>>> closing tag.
>> I think we can treat this as a bug in sgml-indent-line, which should try
>> and use syntax-ppss or something like that instead of regexps.
> I wonder how that could be fixed exactly. parse-partial-sexp doesn't look
> helpful, because it works with single characters, and sgml is concerned with
> full tags. It also has to handle unclosed tags like <br>, some closing tags
> are optional, and HTML 4 has self-closing tags.

I think just checking after the regexp-match whether the match was found
within a "comment" should do the trick, assuming we can get syntax-ppss
(or some extension thereof) to treat "other modes" as comments.

> If parse-partial-sexp just starts from (point-min), and then skips over
> "comments", it will never visit submode regions this way, no?

That's why we'd need to hook into syntax-ppss to run parse-partial-sexp
on a chunk-by-chunk basis, maybe.  Also parse-sexp-ignore-comments also
affects (for|back)ward-sexp, as well as up-list, which are important
building blocks for indentation algorithms.

> Another thing to consider - having "visibility" into previous chunks of the
> same submode may be more harmful than useful in some cases.

That's OK: the low-level code can't know those things, but the
higher-level code which handles the various chunks can treat different
chunks differently.  E.g. using narrow-to-region for chunks which need
to ignore previous text.


        Stefan