Re: Regular Expressions

* Thus wrote Matt Palermo (webmaster@sweetphp.com): > What exactly does this do: > Your original expression: /< (?!p|br) [^>]* >/x Find '<' not followed by 'p|br' until the first '>' we find. <p class="foo"> - matches < > - matches Its a bit confusing as why the <p *> matches, perhaps the documentation at http://php.net/pcre might explain it a little more. > /< (?<=p|br) [^>]+ >/x > Find '<' until, if 'any charcaters' between, '>' and be sure that 'p|br' exist before 'any characters' And perhaps a little more effecient than the one above: /< (?=p|br) [^>]+ >/x Find '<', followed by 'p|br' until, if 'any characters' between, '>'. The last one probably is a better one since it will fail quickly whereas look behinds are a bit expensive since it will have to match < [^>]+ > before it considers the 'p|br'. > It may work, I just want to understand what it's looking for. HTH, Curt -- "I used to think I was indecisive, but now I'm not so sure."