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

/
/
mg

Test String

Code Generator

Generated Code

re = /(var preferences = {)[\s\S]*(};)/m str = '<!DOCTYPE html> <html> <head> <meta http-equiv=\'x-ua-compatible\' content=\'IE=edge,chrome=1\' /> <meta name="robots" content="nofollow" /> <meta name="robots" content="noindex" /> <meta name="robots" content="noarchive" /> <meta http-equiv="Cache-Control" content="private, no-cache, no-store, must-revalidate, max-age=0" /> <meta http-equiv="Pragma" content="no-cache" /> <meta http-equiv="Expires" content="0" /> <meta http-equiv="Expires" content="Tue, 01 Jan 1980 1:00:00 GMT" /> <meta charset=\'UTF-8\' /> <title>BLANK - FILL WITH CLIENT TITLE</title> <link href=\'css/bpdev.css\' rel=\'stylesheet\' type=\'text/css\' /> <script src=\'https://code.jquery.com/jquery-1.11.1.min.js\'></script> <script>!window.jQuery && document.write(\'<script src="common/js/jquery/jquery-1.11.1.min.js"><\\/script>\');</script> <link rel=\'shortcut icon\' href=\'images/favicon.ico\' type=\'image/x-icon\' /> <style id="antiClickjack">body{display:none !important;}</style> </head> <body id=\'userTools\'> <div id=\'notificationContainer\' data-automation=\'notification_window\'></div> <div id=\'overlay\' class=\'modalOverlay\' data-automation=\'modal_overlay\'></div> <div id=\'dialog\' class=\'modal\' data-automation=\'modal_window\'></div> <div id=\'container\'> <div id=\'header\' data-automation=\'header\'></div> <div id=\'loader\' data-automation=\'content_loader\'></div> <div id=\'content\' data-automation=\'content_area\'></div> </div> <div id=\'copyFooter\' class=\'copyright\' data-automation=\'copyright_footer\'></div> <script src=\'common/js/gateway.framework-min.js\' type=\'text/javascript\'></script> <script src=\'common/js/gateway.app-min.js\' type=\'text/javascript\'></script> <script type=\'text/javascript\'> if (self === top) { var antiClickjack = document.getElementById(\'antiClickjack\'); antiClickjack.parentNode.removeChild(antiClickjack); } else { top.location = self.location; } (function($) { var preferences = { logo : \'images/logo.png\', logoWidth : 250, logoHeight : 38, logoAlt : \'\', logoLink : \'\', logoutURL : \'../../pkmslogout\' }; Gateway.startGateway(preferences, true); }(jQuery)); </script> </body> </html>' # 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