Regular Expressions 101

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/
\%\(\s*[\w\s\$\(\)=\.]*\s*\)
/
gm
\% matches the character % with index 3710 (2516 or 458) literally (case sensitive)
\( matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[\w\s\$\(\)=\.]
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\w matches any word character (equivalent to [a-zA-Z0-9_])
\s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
\$ matches the character $ with index 3610 (2416 or 448) literally (case sensitive)
\( matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
\) matches the character ) with index 4110 (2916 or 518) literally (case sensitive)
= matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\) matches the character ) with index 4110 (2916 or 518) 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.

Regular Expression
No Match

/
/
gm

Test String