Re: State-machine based syntax highlighting

[address@hidden]

Stefan Monnier wrote:
>
> Actually, font-locking *is* implemented in C.  The elisp part usually takes
> a negligible amount of time.  The problem start appearing when the
> functionality of the C code is not sufficient and you start trying to parse
> the code in elisp, which is slow.

Good to know. I thought font-lock was implemented in elisp and didn't
bother to check.

BTW, I checked the situation in the enemy camp and seems they also have
problems with performance:

- The colors are wrong when scrolling bottom to top.
        Vim doesn't read the whole file to parse the text.  It starts parsing
        wherever you are viewing the file.  That saves a lot of time, but
        sometimes the colors are wrong.  A simple fix is hitting CTRL-L.  Or
        scroll back a bit and then forward again.
        For a real fix, see |:syn-sync|.  Some syntax files have a way to make
        it look further back, see the help for the specific syntax file.  For
        example, |tex.vim| for the TeX syntax.

...

Displaying text in color takes a lot of effort.  If you find the
displaying
too slow, you might want to disable syntax highlighting for a moment:

        :syntax clear

When editing another file (or the same one) the colors will come back.

http://vimdoc.sourceforge.net/htmldoc/usr_06.html