Python regex to match multiple times

python regex multiple-matches
mavili picture mavili · Jul 1, 2013 · Viewed 34.9k times · Source

I'm trying to match a pattern against strings that could have multiple instances of the pattern. I need every instance separately. re.findall() should do it but I don't know what I'm doing wrong. 

pattern = re.compile('/review: (http://url.com/(\d+)\s?)+/', re.IGNORECASE)
match = pattern.findall('this is the message. review: http://url.com/123 http://url.com/456')

I need 'http://url.com/123', http://url.com/456 and the two numbers 123 & 456 to be different elements of the match list.

I have also tried '/review: ((http://url.com/(\d+)\s?)+)/' as the pattern, but no luck.

Answer

Narendra Yadala picture Narendra Yadala · Jul 1, 2013

Use this. You need to place 'review' outside the capturing group to achieve the desired result.

pattern = re.compile(r'(?:review: )?(http://url.com/(\d+))\s?', re.IGNORECASE)

This gives output

>>> match = pattern.findall('this is the message. review: http://url.com/123 http://url.com/456')
>>> match
[('http://url.com/123', '123'), ('http://url.com/456', '456')]

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