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 = '{ server: \'nginx/1.21.0\', date: \'Mon, 25 Apr 2022 11:34:20 GMT\', \'content-type\': \'text/html; charset=UTF-8\', \'transfer-encoding\': \'chunked\', \'x-powered-by\': \'PHP/7.4.16\', expires: \'Sun, 19 Nov 1978 05:00:00 GMT\', \'cache-control\': \'no-store, no-cache, must-revalidate, max-stale=0, private, post-check=0, pre-check=0\', \'x-content-type-options\': \'nosniff\', \'content-security-policy\': "frame-ancestors \'self\';", \'set-cookie\': [ \'SSESS8b04132f4690dc8ceb7837d5134a5519=ZbgVsmpp6DBRWwNCRMm5DTpfEoKffsNM7l8ILoCWkug; path=/; domain=test.net; secure; HttpOnly\', \'su=1; expires=Thu, 22-Apr-2032 11:34:20 GMT; Max-Age=315360000; path=/; domain=test.net\', \'lt=deleted; expires=Thu, 01-Jan-1970 00:00:01 GMT; Max-Age=0; path=/; test.net\', \'dtCookie=v_4_srv_10_sn_6364C36040ADFF47B91A838BB8B2CADD_perc_100000_ol_0_mul_1_app-3Aea7c4b59f27d43eb_1; Path=/; Domain=test.net\', \'870be6fb89fc78ad2ca0eca3828e3019=7055c78f3c2b7311a5c77934caad6939; path=/; HttpOnly; Secure; SameSite=None\' ], \'x-oneagent-js-injection\': \'true\', \'x-ruxit-js-agent\': \'true\', \'server-timing\': \'dtSInfo;desc="0", dtRpid;desc="493206686"\', connection: \'close\' }'; my $regex = qr/(SSESS.*)=(.+?);\s*path/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