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

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '[Example] öäüß asdf 1234 (1aö) [Red] Panda (It\'s so cute) [Red] The Panda (It\'s so cute), [Red] what Panda (It\'s so cute) (not necessary), [Red] it\'s a Panda (It\'s so cute) (unusual), [Yellow] Leopard (the big one) [Yellow] The Leopard (the big one), [Yellow] what Leopard (the big one) (not needed), [Yellow] it\'s a Leopard (the big one) (unusual), [Green] Dragon (Fire? It\'s hot!) [Green] The Dragon (Fire? It\'s hot!), [Green] what Dragon (Fire? It\'s hot!) (not usual), [Green] it\'s a Dragon (Fire? It\'s hot!) (unusual), [Blue] Snake (zzzZZZzzzZZZ) [Blue] The Snake (zzzZZZzzzZZZ), [Blue] what Snake (zzzZZZzzzZZZ) (not beautiful), [Blue] it\'s a Snake (zzzZZZzzzZZZ) (unusual), Panda (It\'s so cute) The Panda (It\'s so cute), what Panda (It\'s so cute) (not necessary), it\'s a Panda (It\'s so cute) (unusual), Leopard (the big one) The Leopard (the big one), what Leopard (the big one) (not usual), it\'s a Leopard (the big one) (unusual), Dragon (Fire? It\'s hot!) The Dragon (Fire? It\'s hot!), what Dragon (Fire? It\'s hot!) (not necessary), it\'s a Dragon (Fire? It\'s hot!) (unusual), Snake (zzzZZZzzzZZZ) The Snake (zzzZZZzzzZZZ), what Snake (zzzZZZzzzZZZ) (not beautiful), it\'s a Snake (zzzZZZzzzZZZ) (unusual), Panda The Panda, what Panda (not necessary), it\'s a Panda (unusual), Leopard The Leopard, what Leopard (not needed), it\'s a Leopard (unusual), Dragon The Dragon, what Dragon (not usual), it\'s a Dragon (unusual), Snake The Snake , what Snake (not beautiful), it\'s a Snake (unusual),'; my $regex = qr/^(?:\[[^\]\[\n]*\]\s+)?(?<name>[^)(\n]*)\s*(\((?!not|unus)[^)(\n]*\))?/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