Font-lock of comments using comment tokens, does it work?

[Björn Lindqvist]

Hello emacs,

I have a really complicated font-locking problem I'm trying to solve
for a major mode. It's like I've tried everything but nothing
works. Here is the question I asked on Stack Overflow and got some
help with but it didn't go all the way:

http://stackoverflow.com/questions/29973458/avoid-font-locking-interfering-inside-of-comments

I want to font-lock to understand that two short strings, e.g FOO and
BAR are the comment tokens. The tokens themselves should be
font-locked as comments and everything following them until the end of
line should also be comments.

The problem is that the strings only start comments if they are
free-standing tokens. So on these four lines there are comments:

    random code FOO random comment
    stuff BAR comment "with stuff"
    BAR FOO BAR
    FOO

On these four lines there are NO comments:

    FOObar random come
    BARFOO random code
    random code xyFOOzw
    random code "with string FOO " etc ...

Because the comment tokens are not separate. I'm suspecting that I've
found a limitation in emacs font-locking and that this is impossible
to get completely right. I'd love to be proven wrong though. :)


-- 
mvh/best regards Björn Lindqvist