python regex: extract a string between 2 values without including patterns

Question

I have a string:

a="12cdanfaw3i8hanjwofaef56ghah398hafadsf12cds;dkh38hfasdf56ghaldkshf12cdasdiuhf93f2asdf56gh"

I'm trying to extract a string between 12cd and 56gh. Those values would be anfaw3i8hanjwofaef, s;dkh38hfasdf, asdiuhf93f2asdf

The regex that I have is re.findall(r'12cd.*56gh', a).

But the patterns are included in the output.

How do I write the regex to not include it in the output?

Thanks

How does Python deal with regex captures? `r'12cd(.*)56gh'` – lit Mar 23 '18 at 20:53 — lit, Mar 23 '18 at 20:53

user3483203 · Accepted Answer · 2018-03-23T20:35:18.840

4

You need a non-greedy regex to get all 3 matches, and you also need to use a matching group to not include the pattern, so use 12cd(.*?)56gh

import re
print(re.findall(r'12cd(.*?)56gh', '12cdanfaw3i8hanjwofaef56ghah398hafadsf12cds;dkh38hfasdf56ghaldkshf12cdasdiuhf93f2asdf56gh'))

Output:

['anfaw3i8hanjwofaef', 's;dkh38hfasdf', 'asdiuhf93f2asdf']

Explanation

12cd              // matches 12cd
    (             // matching group 1
      .*?         // matches any character between 0 and unlimited times, lazy
    )             
56gh              // matches 56gh

edited Mar 23 '18 at 20:35

answered Mar 23 '18 at 20:29

user3483203

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What does ? do? – Carol Ward Mar 23 '18 at 20:35
`*?` will match between 0 and unlimited times, but match as few times as possible, expanding as necessary. – user3483203 Mar 23 '18 at 20:36

python regex: extract a string between 2 values without including patterns

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