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 = '{"severity":"INFO","ts":1704101563.224535,"logger":"controller","msg":"Seccomp profile \'not configured\' is not allowed for container \'splunk-fluentd-k8s-objects\'. Found at: no explicit profile found. Allowed profiles: {\\"RuntimeDefault\\", \\"docker/default\\", \\"runtime/default\\"}","process":"audit","audit_id":"2024-01-01T09:32:31Z","details":{},"event_type":"violation_audited","constraint_group":"constraints.gatekeeper.sh","constraint_api_version":"v1beta1","constraint_kind":"K8sPSPSeccomp","constraint_name":"cis-k8s-v1.5.1-psp-seccomp-default","constraint_namespace":"","constraint_action":"warn","resource_group":"","resource_api_version":"v1","resource_kind":"Pod","resource_namespace":"idmzct0-ito-utils-splunkdc-callsign","resource_name":"gkeusr-idmzc-dev-tier0-01-splunk-kubernetes-objects-5686d96j7nj","resource_labels":{"app":"splunk-kubernetes-objects","engine":"fluentd","pod-template-hash":"5686d96bd8","release":"gkeusr-idmzc-dev-tier0-01"}} Show syntax highlighted cluster_name = gkeusr-idmzc-dev-tier0-01container_name = managerhost = npool-cos-apps-medium-7b7dd5cdb8-s6lrpnamespace = gatekeeper-systempod = gatekeeper-audit-789888c597-q9vt8severity = INFOsource = /var/log/containers/gatekeeper-audit-789888c597-q9vt8_gatekeeper-system_manager-da5f687a6b53035c4299f8e3c5cc941c510756de883f2f0e68e783cd4edc7191.logsourcetype = kube:container:manager'; my $regex = qr/\"app\":\"splunk-kubernetes-objects\"/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