Regular Expressions 101

Explanation

Pro

Positive Lookbehind(?<=by )

by the literal text by (case insensitive)

Group 1(\w+ \w+)

\w+any word character, repeated at least once

the literal (32₁₀ / 40₈ / 20₁₆)

\w+any word character, repeated at least once

Non-Capturing Group(?:, *)?

?repeats the group contents below at most once:

,the literal , (44₁₀ / 54₈ / 2C₁₆)

*the literal (32₁₀ / 40₈ / 20₁₆) , repeated any number of times

Group 2(\w+ \w+)?

?repeats the group contents below at most once:

\w+any word character, repeated at least once

the literal (32₁₀ / 40₈ / 20₁₆)

\w+any word character, repeated at least once

Non-Capturing Group(?: *)

*the literal (32₁₀ / 40₈ / 20₁₆) , repeated any number of times

Non-Capturing Group(?:and (\w+ \w+))?

?repeats the group contents below at most once:

and the literal text and (case insensitive)

Group 3(\w+ \w+)

\w+any word character, repeated at least once

the literal (32₁₀ / 40₈ / 20₁₆)

\w+any word character, repeated at least once

Global pattern flags

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

g modifier: global. Finds all matches instead of stopping after the first

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25 tokens

(?<=by )(\w+ \w+)(?:, *)?(\w+ \w+)?(?: *)(?:and (\w+ \w+))?

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