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
Processing...

Test String

Code Generator

Language

Generated Code

use strict; my $str = 'Examples that work [COI vol 5] Post title Post title (coi ch 890+) Post title (coi general) Post [Lotm something] title Examples that don\'t work [coi] with no vol/ch specification or the "general" keyword [idk lotm] lotm/coi must be at the start (Coi ch 8 cool) " cool" should be outside the brackets Lotm Tests [Lotm] Title here [LOM] Title here [Lotm ] Title here [LOM Vol 3] Lotm works with anything after it [Lom vol 3] Lotm works with anything after it [lotm random] stuff (lotm not closed fails COI tests [COI] fails [COI vol 3] Title here [COI ch850+] Title here [COI 231] Assumed this is the chapter # [coi352] a lazy person [COIvol3] Spacing Optional [COIch.3] Spacing Optional [coi231] lower case is fine [COIch293] hopefully no one does this in practice lol [COI vol 5 ch 894] should work [coi vol5 ch23] [coivol2ch.43] [coi chs 253-455] chapter range (coi vol 3&5) & character added [coi chs 231] [COI random] fails Anime/donghua tests (unadvertised) (donghua ep1) just added this, unadvertised though (anime trailer) unadvertised'; my $regex = qr/(?i:(\[|\()(((donghua|anime).*)|((LOM|LotM|COI)( ?)(Vol|(Volume)?)( ?)([0-9\-&]*)( ?)(Chapter|Chap|(Ch)?)(.?)( ?)([0-9\-&]+|general|end)(\+?)([ \/]?privilege)?))(]|\)))/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