Including OR in a regex pattern (PHP)

Question

Trying to create a pattern that includes an or condition.

$pattern["body"]='/(<\/a><\/li><\/ul><\/div><p>|<h2>)(.*)<div class="like">/s';

The pattern should recognize any text between a series of "<\/a><\/li><\/ul><\/div><p>" or a "<h2>" as the beginning delimiter, but apparently the or condition does not work in this case. Anyone can offer a hint for the correct syntax!? I am striving for 1 hour and I have lost the focus and patience in this rule. THank you in advance.

You specified `ereg` in the question title. I should point out that the `ereg` functions in PHP have been deprecated and shouldn't be used any more. You should be using the `preg_` fuctions instead. See the PHP manual for more. — Spudley, Oct 06 '11 at 20:42
[NO REGEX HTML](http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags/1732454#1732454) — cwallenpoole, Oct 06 '11 at 20:46

score 1 · Accepted Answer · answered Oct 06 '11 at 20:40

1

"(?<=</a></li></ul></div>|<h2>).*"

see below grep test:

kent$  echo "</a></li></ul></div>something"|grep -Po "(?<=</a></li></ul></div>|<h2>).*"                                                  
something

kent$  echo "<h2>something"|grep -Po "(?<=</a></li></ul></div>|<h2>).*"                                                                  
something

answered Oct 06 '11 at 20:40

Kent

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Thank you! What does the ?<= do? – Al-Punk Oct 06 '11 at 21:06
1

@Armand go to http://docs.python.org/library/re.html, and search "(?<=" you will see. – Kent Oct 06 '11 at 21:16
Thank you. That means that there was a need for _positive lookahead assertion_ – Al-Punk Oct 06 '11 at 21:26
1

Actually that's a *positive **lookbehind** assertion* – nachito Oct 06 '11 at 21:55

score 0 · Answer 2 · answered Oct 06 '11 at 21:07

0

'%(</a></li></ul></div><p>|<h2>)(.*)<div class="like">%s'

I don't have any sample data to test against but it looks like you were there. I only changed the delimiter so it wouldn't have to be escaped, I find it's easier to understand.

answered Oct 06 '11 at 21:07

nachito

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Thank you for the reply. For some unclear reason it does not work, but the example provided above from Kent works. – Al-Punk Oct 06 '11 at 21:11
@Armand - so, then the differences are the extra `
` and the trailing `
` in the regex. If Kent's worked then your problem statement is incorrect.
– Oct 06 '11 at 21:47
I added the extra
and the
in Kent's code. The secret was the ?<=
– Al-Punk Oct 06 '11 at 21:54
1

If you added the extra's back, I would say your lucky that it apparently PHP (PCRE) allows alternation with its fixed length lookbehinds. As soon as there is a spurrious whitespace between tags it might fail. – Oct 06 '11 at 23:33

score 0 · Answer 3 · answered Oct 06 '11 at 21:39

This might work http://www.ideone.com/zYB1n
But, I'm no php expert.

$regex = '/(?:<\/a>\s*<\/li>\s*<\/ul>\s*<\/div>\s*<p>|<h2>)(?<Text>[\S\s]*)(?=<div class="like">)/';
if (preg_match( $regex, $str1, $matches ))
  print_r( $matches['Text'] );

Including OR in a regex pattern (PHP)

3 Answers3