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 class="main"> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <title>Test_Results_20240621_0910</title> <script type="text/javascript" src="Test_Results_20240621_0910/js/jquery-1.3.2.min.js"></script> <script type="text/javascript" src="Test_Results_20240621_0910/js/jquery.ui.custom-1.8.7.min.js"></script> <script type="text/javascript" src="Test_Results_20240621_0910/js/jquery.dynatree-1.2.4.min.js"></script> <script type="text/javascript" src="Test_Results_20240621_0910/js/jquery.cookie-1.3.1.min.js"></script> <script type="text/javascript" src="Test_Results_20240621_0910/js/jquery.splitter-1.5.1.min.js"></script> <script type="text/javascript" src="Test_Results_20240621_0910/js/dotcover.report.js"></script> <link rel="stylesheet" type="text/css" href="Test_Results_20240621_0910/css/dotcover.report.css"> <link rel="stylesheet" type="text/css" href="Test_Results_20240621_0910/css/dotcover.report.gen.css"> <link rel="stylesheet" type="text/css" href="Test_Results_20240621_0910/css/jquery.dynatree.css"> </head> <body> <div class="header"><span class="title">Test_Results_20240621_0910 Coverage Report</span><span class="info">Generated: Friday, June 21, 2024 09:14:13</span></div> <div class="content" id="content"><div id="coverageTree"></div><iframe id="sourceCode"></iframe></div> <div class="footer">JetBrains dotCover 2024.1.3 Copyright &copy; 2010-2024 <a href="https://www.jetbrains.com/dotcover/" target="_blank">Product Homepage</a> | <a href="https://www.jetbrains.com/feedback/feedback.jsp?product=dotCover&build=3&timezone=Eastern Standard Time" target="_blank">Feedback</a> | <a href="https://www.jetbrains.com/" target="_blank">Company</a></div> <script type="text/javascript"> var resourceFolder = "Test_Results_20240621_0910"; var blockSize = 50000; block0 = [["Total",47,,,,,,1,2],["Group1",29,0,,,,,3,5],["Group2",52,0,,,,,8,4]]; coverageData = [block0]; </script> </body> </html>'; my $regex = qr/\["(Total|Group1|Group2)",(\d+),\d*,,,,,\d+,\d+\]/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