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Result: Matches Does not match starting at the black triangle slider
Unit Tests (showhide) Help You haven't added any unit tests yet {{unitTestModel.tests.length}} Total Tests: Passing ({{unitTestModel.tests.length}}); Failing ({{unitTestModel.failing.length}})
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Expected Matches (hover over highlights for details) Actual Matches  Edit   Passing 
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{{flavors[reModel.flavor].external}} regex quick reference (hide):
[abx-z] One character of: a, b, or the range x-z
[^abx-z] One character except: a, b, or the range x-z
a|b a or b
a? Zero or one a's (greedy)
a?? Zero or one a's (lazy)
a* Zero or more a's (greedy)
a*? Zero or more a's (lazy)
a+ One or more a's (greedy)
a+? One or more a's (lazy)
a{4} Exactly 4 a's
a{4,8} Between (inclusive) 4 and 8 a's
a{9,} 9 or more a's
(?>...) An atomic group
(?=...) A positive lookahead
(?!...) A negative lookahead
(?<=...) A positive lookbehind
(?<!...) A negative lookbehind
(?:...) A non-capturing group
(...) A capturing group
(?P<n>...) A capturing group named n
^ Beginning of the string
$ End of the string
\d A digit (same as [0-9])
\D A non-digit (same as [^0-9])
\w A word character (same as [_a-zA-Z0-9])
\W A non-word character (same as [^_a-zA-Z0-9])
\s A whitespace character
\S A non-whitespace character
\b A word boundary
\B A non-word boundary
\n A newline
\t A tab
\cY The control character with the hex code Y
\xYY The character with the hex code YY
\uYYYY The character with the hex code YYYY
. Any character
\Y The Y'th captured group
(?1) Recurse into numbered group 1
(?&x) Recurse into named group x
(?P=n) The captured group named 'n'
(?#...) A comment

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