bug#192: regexp does not work as documented

[Stefan Monnier <monnier@iro.umontreal.ca>]

> I'm proposing that font-lock divide keywords into two or three
> classes, ordinary, multi-line, and maybe mega-line, matches for
> multi-line and mega-line keywords would be over much larger
> regions. Here is how it might work with two classes (keep in mind that
> I don't yet have a thorough understanding of font-lock and jit-lock):

I do not understand how you propose to solve the main problem:
Let's say you want to fontify a line spanning chars 100..200 and
a multiline region spanning 0..400.  Before fontifying, you need
to unfontify.  The region 100..200 can be completely unfontified, but
what about 0..99 and 201..400?  You can't unfontify them completely
since you don't want to refontify them completely either, so you'd need
to figure out which part of the fontification comes from the
multiline keywords.

Also, the order between keywords is important, so unless you force all
multiline keywords to go at the very end, you'd also need to remove (on
the 0..99 and 201..400 regions) the fontification coming from small
keywords that were placed after multiline keywords and reapply
it afterwards?


        Stefan