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

r"
"
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '04.march.2012 9:07:00 1999-03-22T05:06:07.000 20150420 14 мая 2015 08:30:43 1999 03 22T05:06:07.000+01:00 22.3.19 5:06:07 5:06:07 22.3.19 22. March 1999 1999-03-22 5:06:07.PD March 22, 1999 March 22 1999 22/3/1999 5:06 AM Mar 22 05:06:07 CET 1999 Mon Mar 22 05:06:07 CET 1999 Monday, March 22, 1999 5:06:07 o\'clock AM CET 22-Mar-1999 5:06:07 AM CET 22-Mar-1999 5:06:07 CET AM 1999-03-22 5.06.07.PD CET Monday, March 22, 1999 5:06:07 AM CET'; my $regex = qr/(?:(?P<EngDate>[a-zA-Z]+\s)??(?P<Date0>(?<!\.)(?:\d{1,2}(?=[,\s.\/-])|\d{4}))\.??(?(1),?)(?P<d_sep>[\s\.\/-])?(?:(?P<Date1>[^\W\d_]+|\d{1,2})(?(3)(?P=d_sep)))?(?(1)(?:\s\d{2}:\d{2}:\d{2}\s\w+\s)?)(?P<Date2>\d{2}|\d{4})(?!\:|\.|\d))|(?:(?<!\d{2})(?P<Hours>[0-2]?\d)[\:\.](?P<Minutes>[0-6]\d)(?:[\:\.](?P<Seconds>[0-6]\d))?(?:[,\.](?P<SenodsFraction>\d{3}|\d{6}))?(?:\so'clock)?(?:(?:[\.,\s,\w+\s]?(?:(?P<Z>(?:[a-zA-Z]{3,5})|(?:[+-]\d\d?:?[0,3,4]?[0,5]?))|(?P<s>PD|AM|PM|am|pm)))+)?)/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