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

/
/
gmx

Test String

Code Generator

Language

Generated Code

re = /^(?: # non-capture group (repeat) (?| # branch reset for group 1 ([^)(><\n])| # either non-bracket... or: <(?=.*(>))| # if < open angle capture > to group 1 >(?=.*(<))| # if > capture opening < to group 1 \((?=.*(\)))| # same for (), if ( capture ) to group 1 \)(?=.*(\()) # if ) catpure ( to group 1 )(?=.*((?(2)\1\2|\1))$) # cond (2): if not outer chr (fwd ref) )*? # as few as possible (lazy) \/ eof non-cap [^)(><\n]? # the middle character (no parens) \2$ # the right part (group 2 capture)/mx str = '(_)tar<>rat(_) )()_<(*&bab&*)>_()( )(*?*)( ()<_<oxxo>_>() <__>w(owiwo)w<__> a(t<()((<oyo>))()>t)a v (_)tar<>rap(_) )()_<(*&bab&*)>_))( )(*?*)(. ()<-<oxxo>_>() <__>w(ow(wo)w<__> at<()((<oyo>))()>t)a' # Print the match result str.scan(re) do |match| puts match.to_s end

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