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Postings from August 2000
On Wed, Aug 09, 2000 at 09:53:10PM -0400, Rick Delaney wrote:
> > The most useful may be \F{!<} (FINISH, mark positions before this one
> > as "failing", and restart the whole match). Since the positions
> > before the given one are marked as "failing", the match will restart
> > at the current position (as if pos() and \G .*? were present).
>
> And this one I can think of as "flag" (okay, I'm stretching now).
>
> I'm not sure if I'm fully understanding this one, though. Wouldn't this
> regexp need to be grouped and followed by some other regexp to be
> useful? As it's written I don't see why it needs \F.
*It* needs \F? Which "it"? The example is below.
> > Then one could match comments in C code without preprocessor commands
> > by
> >
> > ' ( \\. | [^\\'] )+ ' \F{!<}
> > |
> > " ( \\. | [^\\"] )* " \F{!<}
> > |
> > /\* .*? */
>
> If the above is $comments then I can see
>
> /($comments)WHATEVER/
>
> being very useful when WHATEVER isn't found, since \F eliminates all the
> possibilities before it (if I'm following).
It is supposed to be used as /$comment/. Consider
const char * comment_start = "/*"; /* Assume C by defaut */
The above REx will correctly find the comment in this line.
Hope this is clearer,
Ilya