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 = 'AppMessages - Dev AppMessages - Master AppMessages2 - Dev AppMessages2 - Master AWS - Octopus Release BellHop - Dev BellHop - Master Bellhop Model - Dev Bellhop Model - Master Bellhop Model V2 - Dev Bellhop Model V2 - Master BellHop Services - Dev BellHop Services - Master BSG Log4j Extras - Dev BSG Log4j Extras - Master BSG Log4j Extras V2- Dev BSG Log4j Extras V2- Master BSG-BOM - Dev BSG-BOM - Master BSG-BOM2 - Dev BSG-BOM2 - Master Core Model - Dev Core Model - Master Core Model V2 - Master Core Model V2- Dev Core Services - Dev Core Services - Master Core Services V2 - Dev Core Services V2 - Master DealerLocator - Dev EMS Services - Dev EMS Services - Master EMS Services V2 - Dev EMS Services V2 - Master Entitlements Services - Dev Entitlements Services - Master Entitlements SOAP API - Dev Laipac Service - Master Laipac Services - Dev Laipac Services V2 - Dev Laipac Services V2 - Master LDK Services - Dev LDK Services - Master LDK Services V2 - Dev LDK Services V2 - Master LicenseAdmin - Dev LicenseAdmin - Master LiteFlexNetIntegration - Dev LiteFlexNetIntegration - Master LiteIntegration - Dev LiteIntegration - Master LiteLib - Dev LiteLib - Master Logviewer - Dev Logviewer - Master Messaging Services - Dev Messaging Services - Master OptionKeys - Dev OptionKeys - Master OptionKeysAPI - Dev OptionKeysAPI - Master Pools API - Dev Pools API - Master Pools Model - Dev Pools Model - Master Pools Model V2 - Dev Pools Model V2 - Master Pools Services - Dev Pools Services - Master Pools Services V2 - Dev Pools Services V2 - Master SubscriptionManager - Dev SubscriptionManager - Master SubscriptionManager2 - Dev SubscriptionManager2 - Master Tid Services - Dev Tid Services - Master TidHTTP - Dev TidHTTP - Master Upload templates to S3 - branch2Dev Upload templates to S3 - Dev Upload templates to S3 - Master Upload templates to S3 - Test VirtualWarehouse - Dev VirtualWarehouse - Master VirtualWarehouse Services - Dev VirtualWarehouse Services - Master VirtualWarehouse Services V2 - Dev VirtualWarehouse Services V2 - Master VW Axiom - Dev VW Axiom - Master VW Lite API - Dev VW Lite API - Master VW Remedy Events - Dev VW Remedy Events - Master VW Remedy Events Consumer - Dev VW Remedy Events Consumer - Master VW Remedy Events Lib - Dev VW Remedy Events Lib - Master VW Scheduled Tasks - Dev VW Scheduled Tasks - Master VW Sentinel - Dev VW Sentinel - Master VW Subscriptions - Dev VW Subscriptions - Master VW5 - Dev VW5 - Master WooCommerce API - Dev WooCommerce API - Master WooCommerce Model - Dev WooCommerce Model - Master WooCommerce Model V2 - Dev WooCommerce Model V2 - Master WooCommerce Services - Dev WooCommerce Services - Master WooCommerce Services V2 - Dev '; my $regex = qr/^([[:alpha:]]+\s)+((V2)\s-\s).*$/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