Re: [PHP] Re: need some regex help to strip out // comments but not http:// urls

On Wed, May 29, 2013 at 6:08 PM, Sean Greenslade <[email protected]>wrote:

> On Wed, May 29, 2013 at 9:57 AM, Jonesy <[email protected]> wrote:
> > On Tue, 28 May 2013 14:17:06 -0700, Daevid Vincent wrote:
> >> I'm adding some minification to our cache.class.php and am running into
> an
> >> edge case that is causing me grief.
> >>
> >> I want to remove all comments of the // variety, HOWEVER I don't want to
> >> remove URLs...
> >
> > KISS.
> >
> > To make it simple, straight-forward, and understandable next year when I
> > have to re-read what I've written:
> >
> > I'd change all "://" to "QqQ"  -- or any unlikely text string.
> >
> > Then I'd do whatever needs to be done to the "//" occurances.
> >
> > Finally, I'd change all "QqQ" back to "://".
> >
> > Jonesy
>
> Wow. This is just a spectacularly bad suggestion.
>
> First off, this task is probably a bit beyond the capabilities of a
> regex. Yes, you may be able to come up with something that works 99%
> of the time, but this is really a job for a parser of some sort. I'm
> sorry I don't have any suggestions on exactly where to go with that,
> however I'm sure Google can be of assistance. The main problem is that
> regex doesn't understand context. It just blindly finds patterns. A
> parser understands context, and can figure out which //'s are comments
> and which are something else. As a bonus, it can probably understand
> other forms of comments like /* */, which regex would completely die
> on.
>
>
It is possible to write a whole parser as a single regex, being it terribly
long and complex.
That said, there's no other simple syntax that would work, for example in
javascript you could to the following:
var http = 5;
switch(value) {
    case http:// Http case here! (this whould not be deleted)
        // Do something
}
But most likely you wouldn't care about that..

- Matijn