Regular Expressions 101

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/
.?(\*\!)(\w*){1,}
/
gm
.
matches any character (except for line terminators)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
1st Capturing Group
(\*\!)
\* matches the character * with index 4210 (2A16 or 528) literally (case sensitive)
\! matches the character ! with index 3310 (2116 or 418) literally (case sensitive)
2nd Capturing Group
(\w*){1,}
{1,} 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
\w
matches any word character (equivalent to [a-zA-Z0-9_])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
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