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

/
/

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'var variants = []; variants[208091] = [[80.00, 958, new Image(), \'8.00\', 80.00, "LUG-CENTRIC-SPACERS"],{},{},[]]; variants[208091][1][36366] = 237228; variants[208092] = [[80.00, 941, new Image(), \'8.00\', 80.00, "4112-5-55-L"],{},{},[]]; variants[208092][1][36366] = 237229; variants[208093] = [[80.00, 957, new Image(), \'8.00\', 80.00, "4112-5-55-LM"],{},{},[]]; variants[208093][1][36366] = 237230; variants[208094] = [[80.00, 954, new Image(/r), \'8.00\', 80.00, "4112-6-55-L"],{},{},[]]; variants[208094][1][36366] = 237231; variants[208095] = [[115.00, 948, new Image(1), \'8.00\', 115.00, "4112-8-65-L"],{},{},[]]; variants[208095][1][36366] = 237232; variants[208096] = [[115.00, 958, new Image(69), \'8.00\', 115.00, "4112-8-65-LM"],{},{},[]]; variants[208096][1][36366] = 237233; variants[216938] = [[80.00, 998, new Image(), \'8.00\', 80.00, "4112-6-55-14-L"],{},{},[]]; variants[216938][1][36366] = 244691; variants[216939] = [[115.00, 1000, new Image(), \'8.00\', 115.00, "4112-8-170-L"],{},{},[]]; variants[216939][1][36366] = 244692; variants[218025] = [[80.00, 998, new Image(), \'8.00\', 80.00, "4112-5-45-L"],{},{},[]]; variants[218025][1][36366] = 245809; variants[228776] = [[115.00, 1000, new Image(), \'8.00\', 115.00, "4112-8-180-L"],{},{},[]]; variants[228776][1][36366] = 254512; variants[228819] = [[80.00, 1000, new Image(), \'8.00\', 80.00, "4112-5-150-L"],{},{},[]]; variants[228819][1][36366] = 254558; '; my $regex = qr/variants\[([0-9]{6})\]\[1\]\[([0-9]{1,6})\] \= 237228\;/p; if ( $str =~ /$regex/ ) { 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