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

/
/
gmi

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'My she baby loves loving, my baby loves loving She\'s got what it takes, and she knows how to use it My baby loves loving, my baby loves loving She\'s got what it takes, and she knows how to use it I was lonely once in this great big world Just a nowhere man without a girl \'Till that lucky day when she came my way And she smiled at me as if to say My baby loves loving, my baby loves loving She\'s got what it takes, and she knows how to use it My baby loves loving, my baby loves loving She\'s got what it takes, and she knows how to use it She\'s the only one, makes me feel so good Can\'t believe my love so I knock on wood All my silent fears seem to fly away And she smiled at me as if to say Your baby loves loving, my baby loves loving She\'s got what it takes for me No more lonely nights just waiting for the telephone to ring No more lonely days, my baby\'s taking care of everything I\'m telling you people My baby loves loving, my baby loves loving She\'s got what it takes, and she knows how to use it My baby loves loving, my baby loves loving She\'s got what it takes, and she knows how to use it She\'s the only one, makes me feel so good Can\'t believe my love so I knock on wood All my silent fears seem to fly away And she looked at me as if to say'; my $regex = qr/(\bShe\b)(?:(?!\b(?:she|loves|you)\b).)*(\bloves\b)(?:(?!\b(?:she|loves|you)\b).)*(\byou\b)/mip; 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