Re^2: Regular expression matching

m#(?!.+)(.+)#i
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Nope. That would fail to match on a string like "This is fine.next".

The next ought to work. It does a lookahead for the bad string "" on every character it reconsiders matching, on the internal string.

m#<P>(?:(?!<b>).)+?</P>#i
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Re: Regular expression matching by Abigail-II (Bishop) on Mar 17, 2004 at 13:35 UTC
I submit: `qr %<p>([^<](?:<(?!b>\|/p>)[^<]))</p>%i;` [download] and a benchmark. The solution with the lookahead on each character does much better than I expected: #!/usr/bin/perl use strict; use warnings; use Benchmark qw /cmpthese/; our $abigail = qr %<p>([^<](?:<(?!b>\|/p>)[^<]))</p>%i; our $bart = qr %<P>((?:(?!<b>).)+?)</P>%is; our $corion = qr %<p>((?:[^<]\|<(?!b>)[^>]+>)?)</p>%i; my @names = qw /abigail bart corion/; our @data = <DATA>; my @correct = ('Just another perl hacker', 'this should match', 'What about <a href="http://www.example.com">this</a>?' +, 'And <p>this'); cmpthese -1 => {map {$_ => "\@$_ = map {/\$$_/g} \@data"} @names}; no strict 'refs'; "@$_" eq "@correct" or die ucfirst for @names; __DATA__ <P>Just another perl hacker</P> <P>Just <b>another</b> perl hacker</P> <p>this should match</p> <p>This should <b>not</b> match</p> <p>What about <a href="http://www.example.com">this</a>?</p> <p>And <p>this</p> malformed piece?</p> Rate corion bart abigail corion 6457/s -- -68% -72% bart 19910/s 208% -- -14% abigail 23209/s 259% 17% -- [download] Abigail	[reply] [d/l] [select]
Re: Re^2: Regular expression matching by Hena (Friar) on Mar 17, 2004 at 10:57 UTC
True. Thats why i said that regex in pure html is not easy. I just had to go to eat, so didn't have time to refine it so that it does what you wrote :). I might have gone on route of the first way (more understandle and perhaps faster) eg. `if (m#<P>(.+?)</P># && $1!~m/<b>/i)` [download] Oh, well ;).	[reply] [d/l]