[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: How to make font lock work with comments?
From: |
Pascal J. Bourguignon |
Subject: |
Re: How to make font lock work with comments? |
Date: |
Thu, 30 Dec 2010 19:35:52 +0100 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) |
rusi <rustompmody@gmail.com> writes:
> On Dec 30, 7:09 pm, "Pascal J. Bourguignon" <p...@informatimago.com>
> wrote:
>> rusi <rustompm...@gmail.com> writes:
>> > Im hacking on an apl mode
>> > In other words emacs sees this as a comment-type char (similar to what
>> > it says for semicolon in elisp buffers
>>
>> > And yet in an elisp buffer the ; to EOL is red
>> > but here it is not.
>>
>> Font locking is a tricky matter.
>>
>> (font-lock-add-keywords nil
>> '(("⍝.*" 0 font-lock-comment-face prepend)
>> ("[^\\]\"\\([^\"\\]*\\|\\.\\)\"" 0 font-lock-string-face prepend)))
>
> Thanks Pascal. I gave this (\x235 is that char) and it works
\x235d actually.
> [Else I get some unicode-related messages when I try ot save the el
> file]
I save my files encoded in utf-8. To be sure, you can add on the first
(or second) line a comment containing "-*- coding:utf-8 -*-".
See File Local Variables in emacs documentation.
> (font-lock-add-keywords 'inferior-apl-mode
> '(("\x235d.*" 0 font-lock-comment-face prepend)))
>
> I guess the second line is for strings?
Yes. I wanted to avoid strings containing that character to be colorized
as comments. The order in font-lock-keywords is important.
> Where do I get all the (typical) faces that should be set up for a
> progmode?
One way to find all the existing faces is to type:
M-x customize-face RET TAB
You can use one of the "standard" font-lock-*-face faces, or you can
also create apl specific faces.
> Ive been trying to copy stuff from scheme.el -- is there a better
> model?
>> The main problem is that it uses regular expressions to find the
>> "keywords", but you want syntax coloring. However, there's a way to use
>> it for syntax coloring, since instead of a regular expression, you can
>> use a function here, which will have to set the "matched regions".
>>
>> For example, for an assembler, I wrote a function to parse
>> (syntactically) an assembler line, and matching the fields. It is
>> configured with font-lock-add-keywords as:
>>
>> (font-lock-add-keywords
>> nil
>> (list
>> (list
>> (function search-asm7090-fields)
>> '(1 font-lock-function-name-face) ; labels
>> '(2 font-lock-keyword-face) ; operation codes
>> '(3 font-lock-reference-face) ; arguments
>> '(4 font-lock-comment-face) ; comments
>> '(5 font-lock-preprocessor-face) ; ibsys
>> '(6 font-lock-type-face) ; cols 72-80
>> )))
>
>
> I dont think I really understand this...
Check the documentation of the function font-lock-add-keywords:
C-h f font-lock-add-keywords RET
and the variable font-lock-keywords:
C-h v font-lock-keywords RET
The numbers refers to the regular expression groups.
For example, if you have a regexpp that matches three different parts,
identified by three regexp groups, you can colorize them differently
with:
(font-lock-add-keywords nil
'("\\(procedure\\) +\\([A-Za-z0-9]+\\) *(\\(.*\\));"
(1 font-lock-keyword-face)
(2 font-lock-function-name-face)
(3 font-lock-type-face)))
> In any case I guess I dont need much parsing (for apl)
Right.
--
__Pascal Bourguignon__ http://www.informatimago.com/
A bad day in () is better than a good day in {}.