Regular Expressions 101

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Function

  • Match
  • Substitution
  • List
  • Unit Tests (47)

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An explanation of your regex will be automatically generated as you type.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression

/
/

Unit Tests

given the string https://meta.docs.com assert that regex does match
given the string https://meta.com/dev/docs assert that regex does match
given the string https://meta.documentation.com assert that regex does match
given the string https://docs.dev.meta.com assert that regex does match
given the string https://meta.docs.com/section/page assert that regex does match
given the string https://en.docs.net/en/ assert that regex does match
given the string https://example.com/docs assert that regex does match
given the string https://example.com/documentation assert that regex does match
given the string https://sub.domain.com/docs/index.html assert that regex does match
given the string https://example.com/docs/section/page.ht… assert that regex does match
given the string https://example.com/docs.html assert that regex does match
given the string http://example.com/documentation/index.h… assert that regex does match
given the string https://documentation.example.com assert that regex does match
given the string https://docs.example.com/subpage assert that regex does match
given the string http://example.com/path/to/docs assert that regex does match
given the string http://example.docs.example.com assert that regex does match
given the string https://example.com/notdocs/document.htm… assert that regex does not match
given the string https://example.com/resources/document assert that regex does not match
given the string http://example.com/developer/guide.html assert that regex does match
given the string https://developer.example.com/api assert that regex does match
given the string https://wiki.example.com assert that regex does not match
given the string https://api.example.com/docs assert that regex does match
given the string https://manual.example.com assert that regex does match
given the string https://reference.example.com/docs/api.h… assert that regex does match
given the string https://example.com/documentary assert that regex does not match
given the string http://example.com/references assert that regex does not match
given the string https://example.com/howto assert that regex does not match
given the string https://example.com/manualized assert that regex does not match
given the string http://example.com/learned assert that regex does not match
given the string https://example.com/docs assert that regex does match
given the string https://example.com/documentation assert that regex does match
given the string http://example.com/path/to/docs assert that regex does match
given the string http://example.com/manuals/docs.html assert that regex does match
given the string https://example.com/documentation/v1/hel… assert that regex does match
given the string http://docs.example.com/v2/resources assert that regex does match
given the string https://reference.example.com/resources/… assert that regex does match
given the string https://example.com/help/docs-v3 assert that regex does match
given the string https://example.com/docs/tutorials/index assert that regex does match
given the string http://example.com/resources/tutorial assert that regex does match
given the string http://kb.example.com/manual/index assert that regex does match
given the string https://developer.example.com/resources/… assert that regex does match
given the string http://example.com/support-center assert that regex does not match
given the string https://example.com/developer-tools assert that regex does match
given the string https://help-center.example.com assert that regex does not match
given the string http://example.com/documents assert that regex does not match
given the string http://example.com/wiki-books assert that regex does not match
given the string https://example.com/documentary assert that regex does not match