php clean up regex

Question

hey can i clean up a preg_match in php from this:

preg_match_all("/(".$this->reg['wat'].")?(".$this->reg['wat'].")?(".$this->reg['wat'].")?(".$this->reg['wat'].")?(".$this->reg['wat'].")?(".$this->reg['wat'].")?(".$this->reg['wat'].")?/",$value,$match);

to look like this:

preg_match_all("/
   (".$this->reg['wat'].")?
   (".$this->reg['wat'].")?
   (".$this->reg['wat'].")?
   (".$this->reg['wat'].")?
   (".$this->reg['wat'].")?
   (".$this->reg['wat'].")?
   (".$this->reg['wat'].")?
/",$value,$match);

right now each space, it counts as a ling break so it wont return any finds when searching. but it just looks cleaner and easier to read is why i ask you know. i was looking for one of those letters to add after the closing "/" in the regex. thanks

score 6 · Answer 1 · answered Apr 25 '10 at 23:35

Yes, take a look at the PCRE_EXTENDED option:

x (PCRE_EXTENDED)
If this modifier is set, whitespace data characters in the pattern are totally ignored except when escaped or inside a character class, and characters between an unescaped # outside a character class and the next newline character, inclusive, are also ignored. This is equivalent to Perl's /x modifier, and makes it possible to include comments inside complicated patterns. Note, however, that this applies only to data characters. Whitespace characters may never appear within special character sequences in a pattern, for example within the sequence (?( which introduces a conditional subpattern.

well this is inside a class so is that why its not working? i added it in and it doesn't find any results. — David, Apr 25 '10 at 23:59
This answer has been added to the [Stack Overflow Regular Expression FAQ](http://stackoverflow.com/a/22944075/2736496), under "Modifiers". — aliteralmind, Apr 10 '14 at 00:52

score 3 · Answer 2 · answered Apr 26 '10 at 00:42

3

preg_match_all('/('.$this->reg['wat'].'){0,7}/', $value, $match);

That should be fairly clean.

answered Apr 26 '10 at 00:42

erisco

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i just typed this on the fly, not that simple – David Apr 26 '10 at 01:18
Then you need to correctly define how simple it is, as I will not give you an answer that is unnecessarily convoluted. – erisco Apr 26 '10 at 01:51

score 1 · Answer 3 · answered Apr 26 '10 at 05:08

1

In case it wasn't obvious: (and as an extension/simplified version of VolkerK's answer) add the x flag to the preg_match call:

preg_match_all(".../x",$value,$match);

This will allow you to use newlines without regex actually matching them.

answered Apr 26 '10 at 05:08

Henrik L.

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php clean up regex

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