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 = 'Created a new subnet: +-------------------+------------------------------------------------+ | Field | Value | +-------------------+------------------------------------------------+ | allocation_pools | {"start": "10.42.42.2", "end": "10.42.42.254"} | | cidr | 10.42.42.0/24 | | dns_nameservers | | | enable_dhcp | True | | gateway_ip | 10.42.42.1 | | host_routes | | | id | 3eded702-2909-4515-bf74-7c7c2c7c96e3 | | ip_version | 4 | | ipv6_address_mode | | | ipv6_ra_mode | | | name | Atelier | | network_id | 5d15b14c-1d39-48d5-8f48-0dfd68c98d47 | | tenant_id | d3c17d0e8bd742ed939794a98991886f | +-------------------+------------------------------------------------+ '; my $regex = qr/(?<=\ id\ \|.)(([a-zA-Z0-9_]{8})-([a-zA-Z0-9_]{4})-([a-zA-Z0-9_]{4})-([a-zA-Z0-9_]{4})-([a-zA-Z0-9_]{12}))/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