Regular Expressions 101

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/
(a|c|b[^c])+
/
gm
1st Capturing Group
(a|c|b[^c])+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
1st Alternative
a
a matches the character a with index 9710 (6116 or 1418) literally (case sensitive)
2nd Alternative
c
c matches the character c with index 9910 (6316 or 1438) literally (case sensitive)
3rd Alternative
b[^c]
b matches the character b with index 9810 (6216 or 1428) literally (case sensitive)
Match a single character not present in the list below
[^c]
c matches the character c with index 9910 (6316 or 1438) literally (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String

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