Regular Expressions 101

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/
[a-fA-F0-9]
/
g
Match a single character present in the list below
[a-fA-F0-9]
a-f matches a single character in the range between a (index 97) and f (index 102) (case sensitive)
A-F matches a single character in the range between A (index 65) and F (index 70) (case sensitive)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
g

Test String

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