Regular Expressions 101

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/
((?<raute>#(?<raute_content>[^\n]*))|(?<doubleslashes>\/\/(?<doubleslashes_content>[^\n]*))|(?<block>\/\*(?<block_content>[^*]+|\*(?!\/))*+\*\/))
/
gm
1st Capturing Group
((?<raute>#(?<raute_content>[^\n]*))|(?<doubleslashes>\/\/(?<doubleslashes_content>[^\n]*))|(?<block>\/\*(?<block_content>[^*]+|\*(?!\/))*+\*\/))
1st Alternative
(?<raute>#(?<raute_content>[^\n]*))
Named Capture Group raute
(?<raute>#(?<raute_content>[^\n]*))
# matches the character # with index 3510 (2316 or 438) literally (case sensitive)
Named Capture Group raute_content
(?<raute_content>[^\n]*)
Match a single character not present in the list below
[^\n]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\n matches a line-feed (newline) character (ASCII 10)
2nd Alternative
(?<doubleslashes>\/\/(?<doubleslashes_content>[^\n]*))
Named Capture Group doubleslashes
(?<doubleslashes>\/\/(?<doubleslashes_content>[^\n]*))
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Named Capture Group doubleslashes_content
(?<doubleslashes_content>[^\n]*)
Match a single character not present in the list below
[^\n]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\n matches a line-feed (newline) character (ASCII 10)
3rd Alternative
(?<block>\/\*(?<block_content>[^*]+|\*(?!\/))*+\*\/)
Named Capture Group block
(?<block>\/\*(?<block_content>[^*]+|\*(?!\/))*+\*\/)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
Named Capture Group block_content
(?<block_content>[^*]+|\*(?!\/))*+
*+ matches the previous token between zero and unlimited times, as many times as possible, without giving back (possessive)
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
[^*]+
Match a single character not present in the list below
[^*]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
2nd Alternative
\*(?!\/)
\* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
Negative Lookahead
(?!\/)
Assert that the Regex below does not match
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) 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