[RESOLVED] Negative lookaheads ?

[suntra]

Hi everyone...

Let's say you have a string like this :

START text END

You want to get what is between START and END ( text )... the pattern would be
#START(.*?)END#

BUT, if you have something like this :

START text1 START text2 END END

You want to get text2 first, then text1... So you want something like this :

START (everything different than "END") END

I tried something like this...

#START(?!END)END#

But it doesn't work... modifying to...

#START(?!END*)END#

Doesn't too work and according to PHP.net, I cannot use "repeatitors" with negative lookaheads...

Would something have a brilliant idea about that one ?

Cheers !

[Weedpacket]

Something likecode*[/code] will match as long as "END" doesn't appear (incidentally, it's lookbehind assertions that have to be fixed-length).

It's horrible, and there's surely a cleaner way to do it, but

#START((?>(?:(?!START)(?!END).)*)|(?R))*END#

will match matching START and END pairs at the top level and return those and the bits between; To get deeper ones you'd run each piece through the same pattern.

$pattern = '#START((?>(?:(?!START)(?!END).)*)|(?R))*END#';
$test = 'START foo bar END baz START abc START def END ghi START jkl END END';
preg_match_all($pattern, $test, $m);
print_r($m);

[suntra]

Oh great ! 😃

Here's a little kiss for you : :p (that's the best one I could find !!)

[bradgrafelman]

suntra wrote:

Here's a little kiss for you : :p (that's the best one I could find !!)

Erm... well anyway... uh, don't forget to mark this thread resolved.

[Weedpacket]

Please, no tongues 😃