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"
"
gsim

Test String

Code Generator

Language

Generated Code

use strict; my $str = '{ "34:d2:70:87:42:68;": [ "192.168.1.81", "\\"amazon-8dee0891a\\";" ], "98:e0:d9:91:bc:71;": [ "192.168.1.32", "\\"Cathys-Air\\";" ], "88:71:e5:b3:cb:4e;": [ "192.168.1.172", "\\"amazon-205f4e28e\\";" ], "34:d2:70:7f:df:e7;": [ "192.168.1.76", "\\"amazon-8b38e6c4e\\";" ], "88:71:e5:a2:ff:66;": [ "192.168.1.77", "\\"amazon-43faa4ef3\\";" ], "b8:3e:59:f1:73:9f;": [ "192.168.1.190", "\\"Roku" ], "18:b4:30:14:bc:da;": [ "192.168.1.179", "\\"02AA01AC42140DKR\\";" ], "ac:d1:b8:4d:a3:85;": [ "192.168.1.180", "\\"NPI4DA385\\";" ], "14:91:82:c9:8b:61;": [ "192.168.1.174", "\\"wemo\\";" ], "14:91:82:00:d5:35;": [ "192.168.1.184", "\\"wemo\\";" ], "08:00:27:89:03:db;": ['; my $regex = qr/(192.168.1.\d{1,3}).*?((\w{2}[:]){5}(\w{2}))/simp; 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