I'd like to have a regex capture all instances of a pattern between two delimiters.
Simplified example to one character patterns (goal: capture all b between first x and last z):
bbxabbcbacbedbzbb
^^ ^ ^ ^
should capture the 5 bs.
I tried .*x.*(b).*z.* which only captures the last b. (rubular)
Use
(?:x|(?<!\A)\G).*?\Kb(?=.*z)
See regex proof.
EXPLANATION
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(?: group, but do not capture:
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x 'x'
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| OR
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(?<! look behind to see if there is not:
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\A the beginning of the string
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) end of look-behind
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\G where the last m//g left off
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) end of grouping
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.*? any character except \n (0 or more times
(matching the least amount possible))
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\K match reset operator (omits matched text)
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b 'b'
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(?= look ahead to see if there is:
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.* any character except line breaks (0 or more times
(matching the most amount possible))
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z 'z'
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) end of look-ahead