Regular Expressions 101

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/
(\\n|\\r)+
/
gm
1st Capturing Group
(\\n|\\r)+
+ 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
\\n
\\ matches the character \ with index 9210 (5C16 or 1348) literally (case sensitive)
n matches the character n with index 11010 (6E16 or 1568) literally (case sensitive)
2nd Alternative
\\r
\\ matches the character \ with index 9210 (5C16 or 1348) literally (case sensitive)
r matches the character r with index 11410 (7216 or 1628) 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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