Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.

Regular Expression

Regex Versions


/

Delimiters


/
g

Regex Flags


Unit Tests

/
./
../
../.
.././a
../../a
/a/a..
given the string ~/ assert that regex does match
given the string ~/a assert that regex does match
given the string ~/a/a assert that regex does match
given the string ~/. assert that regex does match
given the string ~/.. assert that regex does match

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Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions