Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • 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
No Match

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /(\w{2})/m str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subst = '0x$1, ' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html