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

Code Generator

Language

Generated Code

use strict; my $str = ' <!DOCTYPE html> <html lang="el" dir="ltr" class="no-js"> <head > <meta charset="utf-8" /> <title>Radial</title> <meta name="description" content="Η Radial σχεδιάζει και αναπτύσσει websites, οργανώνει online καμπάνιες και δημιουργεί εταιρικές ταυτότητες." /> <meta property="fb:page_id" content="118981334805256" /> <meta property="fb:app_id" content="166019300145537" /> <!--[if lt IE 9]><script type="text/javascript" src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script><![endif]--> <script type="text/javascript">(function(H){H.className=H.className.replace(/\\bno-js\\b/,\'js\')})(document.documentElement);</script> <link rel="stylesheet" type="text/css" media="screen" href="http://static.radial.gr/styles/screen.css?43614" /> <script type="text/javascript" src="http://use.typekit.com/ioa2dxy.js"></script> <script type="text/javascript">try{Typekit.load();}catch(e){}</script? <link rel="alternate" type="application/rss+xml" title="Τελευταία έργα" href="/feed/" /> </head> <body id="home" class=""> <header id="main-header"><div class="wrapper"> <div id="logo"><a href="/"><img src="http://static.radial.gr/images/radial-logo.png" alt="Radial" /></a></div> <nav id="main-nav"> <ul> <li><a href="/projects/">Έργα</a></li> <li><a href="/profile/">Προφίλ</a></li> <li><a href="/contact/">Επικοινωνία</a></li> </ul> </nav> <nav id="lang-nav"> <span >EΛ</span> <a href="/en/">EN</a> </nav> <br /> </div></header> <script type="text/javascript"> var _gaq = _gaq || []; _gaq.push([\'_setAccount\', \'UA-515952-44\']); _gaq.push([\'_trackPageview\']); (function() { var ga = document.createElement(\'script\'); ga.type = \'text/javascript\'; ga.async = true; ga.src = (\'https:\' == document.location.protocol ? \'https://ssl\' : \'http://www\') + \'.google-analytics.com/ga.js\'; var s = document.getElementsByTagName(\'script\')[0]; s.parentNode.insertBefore(ga, s); })(); </script> </body> </html> '; my $regex = qr/\<(\w+)(?:\s*\>|\s*\/\>)?/mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html