Regular Expressions 101

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Function

  • Match
  • Substitution
  • List
  • Unit Tests (13)

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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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"

Unit Tests

given the string DA assert that regex does match
given the string D0A assert that regex does match
given the string D30 assert that regex does match
given the string D2F assert that regex does match
given the string D1a assert that regex does match
given the string D1A assert that regex does match
given the string D19 assert that regex does match
given the string D11 assert that regex does match
given the string D10 assert that regex does match
given the string D3 assert that regex does match
given the string D2 assert that regex does match
given the string D1 assert that regex does match
given the string D0 assert that regex does match