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

/
/
i

Unit Tests

given the string 0033 1 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string 033 1 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string 33 1 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string +33 1 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string 00331 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string 0331 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string 331 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string +331 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string 01 02 03 04 05 assert that capture group 1 equals 1 02 03 04 05
given the string 0033102030405 assert that capture group 1 equals 102030405
given the string 033102030405 assert that capture group 1 equals 102030405
given the string 33102030405 assert that capture group 1 equals 102030405
given the string +33102030405 assert that capture group 1 equals 102030405
given the string 0102030405 assert that capture group 1 equals 102030405
given the string 0033 1 02 03 04 05 assert that regex does match
given the string 033 1 02 03 04 05 assert that regex does match
given the string 33 1 02 03 04 05 assert that regex does match
given the string +33 1 02 03 04 05 assert that regex does match
given the string 00331 02 03 04 05 assert that regex does match
given the string 0331 02 03 04 05 assert that regex does match
given the string 331 02 03 04 05 assert that regex does match
given the string +331 02 03 04 05 assert that regex does match
given the string 01 02 03 04 05 assert that regex does match
given the string 0033102030405 assert that regex does match
given the string 033102030405 assert that regex does match
given the string 33102030405 assert that regex does match
given the string +33102030405 assert that regex does match
given the string 0102030405 assert that regex does match