How to extract the first non-Null match from a group of regexp matches in Python?

Posted by bodacydo on Stack Overflow See other posts from Stack Overflow or by bodacydo
Published on 2010-03-23T10:05:06Z Indexed on 2010/03/23 10:13 UTC
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python

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regex

Suppose I have a regular expression (a)|(b)|(c)|(d). If I apply it to text 'foobar' I get a match object

>>> compiled = re.compile('(a)|(b)|(c)|(d)')
>>> compiled.search('foobar').groups()
(None, 'b', None, None)

How do I extract the 'b' from here? Or in general, how do I extract the first match from an unknown number of groups (can happen when the regexp was built dynamically)?

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