Regular Expressions 101

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Branch Reset Group
Subpatterns declared within each alternative of this construct will start over from the same index.
1st Alternative
^ asserts position at start of a line
1st Capturing Group
\d matches a digit (equivalent to [0-9])
2nd Alternative
\D matches any character that's not a digit (equivalent to [^0-9])
1st Capturing Group
\d matches a digit (equivalent to [0-9])
Negative Lookahead
Assert that the Regex below does not match
\d matches a digit (equivalent to [0-9])
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


Test String