RE: [Ctags] [PATCH] vim.c --> added variables and scoping for functions

[Darren H. <da...@hi...>]

On Wed, 11 Apr 2001, Jay Glanville wrote:

> I have some questions concerning the regex declarations using the
> addLanguageRegex.
>
> - Is special character tags like \w for [a-zA-Z_] accepted, or is it
> preferred to use [:alnum:]?

It depends upon what implementation of Posix regex you are linked
against: Gnu regex or System V regex. Gnu regex, used on Linux and
BSD, *does* recognize \b, \B, \<, \>, \w, \W, \`, and \'. If you
need documentation on these, get the Gnu regex package from
http://www.gnu.org (you may not find the detailed docs on your
system by default, even though regex is available in the system libs).

Any Posix implementation should recognize the [:alnum:] form.

> Another question about alpha-numeric.  If I
> have to use [:alnum:], how to I augment this character class to include '_'?
> Would it be like this: [[:alnum:]_]?

As far as I understand it.

> - Am I allowed to use the addLanguageRegex method twice for the same tag
> type?  e.g.:
>   addLanguageRegex( lang, "/^let [:alpha:]:([:alnum:]+)/\\1/v,variable/" );
>   addLanguageRegex( lang, "/^let ([:alnum:]+)/\\1/v,variable/" );

Yes. The only read drawback is that it shows up twice in
--<LANG>--types option description in the --help output.

> What's the difference?  The first one will match "let g:variable = ..."
> while the second one will match "let variable = ...", and both will return
> "variable" as the tag name.  Why do I think I need this?  I need something
> to consume the possible existence of a scope character.  The format for a
> vim variable is like this:
>       let [s:]varname = value
> where s: is optional, and states the scope of the variable.  If anyone knows
> of a better way to do this in a single regex, please let me know.

Try this:

addLanguageRegex( lang, "/^let (([:alpha:]+):)?([:alnum:]+)/\\3/v,variable/" );

> - in the HTML document that comes with the Win32 distribution
> (CTAGS~VT.HTM), in the --regex-<LANG>=... section in the last sentence, you
> say, "You can determine if support for regular expressions is compiled in by
> examining the output of the --version option, which will include "+regex" in
> the compiled feature list."  However, when I use the --version tag, all I
> get is name, copyright and address information.  How do I confirm that my
> binary was compiled with regex?

Then it does not include it. If you want a precompiled Win32 binary
with regex support, get it from the Ctags web site:

    http://ctags.sourceforge.net

-- 
Darren Hiebert <da...@hi...>
http://darren.hiebert.com