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 = '<dl> <dd>[1] <a href="/wiki/Geb%C3%A4ude" title="Gebäude">Gebäude</a>, <a href="/wiki/R%C3%A4umlichkeit" title="Räumlichkeit">Räumlichkeit</a>, <a href="/wiki/Unterkunft" title="Unterkunft">Unterkunft</a> </dd> <dd>[2] die <a href="/wiki/Gemeinschaft" title="Gemeinschaft">Gemeinschaft</a> der <a href="/wiki/Mensch" title="Mensch">Menschen</a>, die unter einem Dach zusammen leben, wohnen oder arbeiten</dd> <dd>[3] der <a href="/wiki/Unterhaltung" title="Unterhaltung">Unterhaltung</a> dienendes Gebäude</dd> <dd>[4] <i><a href="/wiki/Astrologie" title="Astrologie">Astrologie</a>:</i> <a href="/wiki/Tierkreiszeichen" title="Tierkreiszeichen">Tierkreiszeichen</a> </dd> <dd>[5] <a href="/w/index.php?title=Herrscherhaus&amp;action=edit&amp;redlink=1" class="new" title="Herrscherhaus (Seite nicht vorhanden)">Herrscherhaus</a> </dd> <dd>[6] <a href="/wiki/Firma" title="Firma">Firma</a>, <a href="/wiki/Unternehmen" title="Unternehmen">Unternehmen</a> </dd> <dd>[7] <a href="/wiki/scherzhaft" title="scherzhaft"><i>scherzhaft</i></a> <a href="/wiki/Freund" title="Freund">Freund</a> </dd> <dd>[8] <i><a href="/wiki/umgangssprachlich" title="umgangssprachlich">umgangssprachlich</a>:</i> Gehäuse der <a href="/wiki/Schnecke" title="Schnecke">Schnecke</a> </dd> <dd>[9] Gasthaus oder <a href="/wiki/Gastst%C3%A4tte" title="Gaststätte">Gaststätte</a> </dd> </dl> '; my $regex = qr/<a.*<\/a>/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