Regular Expressions 101

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Function

  • Match
  • Substitution
  • List
  • Unit Tests (28)

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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 fe80:0:0:0:0204:61ff:254.157.241.86 assert that regex does match
given the string fe80::204:61ff:254.157.241.86 assert that regex does match
given the string fe80:0000:0000:0000:0204:61ff:254.157.24… assert that regex does match
given the string fe80::204:61ff:fe9d:f156 assert that regex does match
given the string fe80:0:0:0:204:61ff:fe9d:f156 assert that regex does match
given the string fe80:0000:0000:0000:0204:61ff:fe9d:f156 assert that regex does match
given the string empty string assert that regex does not match
given the string ::1 assert that regex does match
given the string fe80:: assert that regex does match
given the string 2001:: assert that regex does match
given the string 2a02:a451:76de::/48 assert that regex does not match
given the string 2001:0db8:85a3:0000:0000:8a2e:0370:7334 assert that regex does match
given the string ::ffff:10.0.0.1 assert that regex does match
given the string 1:2:3:4:5:6:77:88 assert that regex does match
given the string fe08::7:8 assert that regex does match
given the string 1:2:3:4:5:6:7:8:9 assert that regex does not match
given the string 1:2:3:4:5:6:7:8: assert that regex does not match
given the string ::1:2:3:4:5:6:7:8 assert that regex does not match
given the string 1:2:3:4:5:6:7:88888 assert that regex does not match
given the string 192.168.1.1 assert that regex does match
given the string 0.0.0.0 assert that regex does match
given the string 255.255.255.255 assert that regex does match
given the string 10.0.0.1 assert that regex does match
given the string 10002.3.4 assert that regex does not match
given the string 1.2.3.4.5 assert that regex does not match
given the string 256.0.0.0 assert that regex does not match
given the string 260.0.0.0 assert that regex does not match
given the string fe08::7:8interface assert that regex does not match