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

/
/
g

Test String

Code Generator

Language

Generated Code

use strict; my $str = '<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <meta name="robots" content="index,follow"> <meta name="keywords" content="kamerki, erotyczne"> <meta name="description" content="Eroticam.pl"> <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon"> <title>Strona główna | Eroticam.pl</title> <base href="{$_template_root|small_letters}"> <meta property="og:url" content="{$_template_root}"/> <meta property="og:site_name" content="eroticam.pl"/> <meta property="og:title" content="Strona główna | Eroticam.pl"/> <meta property="og:type" content="profile"/> <meta property="og:image" content="/img/logo_big.jpg" /> <meta property="og:description" content="Opis strony"/> <script src="{$_template_root}/js/libs/console.js"></script> <script src="{$_template_root}/js/libs/broadcast.js"></script> <script src="https://cdn.socket.io/socket.io-1.3.5.js"></script> <script src="//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <script src="//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/jquery-ui.min.js"></script> <script src="{$_template_root}/js/jquery.fancybox.pack.js"></script> <link rel="stylesheet" href="{$_template_root}/css/components.css"> <link rel="stylesheet" href="{$_template_root}/css/default/style.css"> <link rel="stylesheet" href="{$_template_root}/css/default/responsive.css"> <link rel="stylesheet" href="{$_template_root}/css/jquery.fancybox.css"> <link rel="stylesheet" href="{$_template_root}/css/unoSlider.css" type="text/css" media="screen" /> <link rel="stylesheet" href="//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/themes/smoothness/jquery-ui.css" /> <meta name="viewport" content="width=device-width, initial-scale=1"> <meta name="google-site-verification" content="1tqMv6H9GEsFbXTZaW8zcngUGvqorZ94csA1v7Nc2qg" /> </head> <body>'; my $regex = qr/{\$(\w+|\w+\|\w+)}/p; 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