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 = ' 2019-01-02T17:34:19-05:00 10.10.30.1 unbound: [48511:0] info: incoming scrubbed packet: ;; ->>HEADER<<- opcode: QUERY, rcode: NOERROR, id: 0 ;; flags: qr rd ra ; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: gs-loc.ls-apple.com.akadns.net.#011IN#011A ;; ANSWER SECTION: gs-loc.ls-apple.com.akadns.net.#01135#011IN#011A#01117.142.171.4 gs-loc.ls-apple.com.akadns.net.#01135#011IN#011A#01117.142.171.8 gs-loc.ls-apple.com.akadns.net.#01135#011IN#011A#01117.142.171.9 ;; AUTHORITY SECTION: ;; ADDITIONAL SECTION: ;; MSG SIZE rcvd: 96 2019-01-02T17:34:42-05:00 10.10.30.1 unbound: [48511:0] info: cname msg ;; ->>HEADER<<- opcode: QUERY, rcode: NOERROR, id: 0 ;; flags: qr rd ra ; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: init-p01md.apple.com.#011IN#011A ;; ANSWER SECTION: init-p01md.apple.com.#0119665#011IN#011CNAME#011init-p01md-lb.push-apple.com.akadns.net. ;; AUTHORITY SECTION: ;; ADDITIONAL SECTION: ;; MSG SIZE rcvd: 91 2019-01-02T18:52:01-05:00 10.10.30.1 unbound: [48511:0] info: msg from cache lookup ;; ->>HEADER<<- opcode: QUERY, rcode: NOERROR, id: 0 ;; flags: qr rd ra ; QUERY: 1, ANSWER: 0, AUTHORITY: 6, ADDITIONAL: 0 ;; QUESTION SECTION: amazonaws.com.#011IN#011DS ;; ANSWER SECTION: ;; AUTHORITY SECTION: xxxxxxxxxxxxxxxxxx.#01181254#011IN#011NSEC3#0111 1 0 - xxxxxxxxxxxxxxxxxxNS SOA RRSIG DNSKEY NSEC3PARAM ;{flags: optout} xxxxxxxxxxxxxxxxxx.com.#01181254#011IN#011RRSIG#011NSEC3 8 2 86400 20190107054258 20181231043258 37490 com. xxxxxxxxxxxxxxxxxx/2/xxxxxxxxxxxxxxxxxx/xxxxxxxxxxxxxxxxxx/xxxxxxxxxxxxxxxxxx= ;{id = 37490} com.#011884#011IN#011SOA#011a.gtld-servers.net. nstld.verisign-grs.com. 1546473084 1800 900 604800 86400 com.#011884#011IN#011RRSIG#011SOA 8 1 900 20190109235124 20190102224124 37490 com. xxxxxxxxxxxxxxxxxx+xxxxxxxxxxxxxxxxxx/xxxxxxxxxxxxxxxxxx/xxxxxxxxxxxxxxxxxx'; my $regex = qr/(?:\G(?!\A)\s*|ANSWER\sSECTION:)\s*(?<answer_name>\S+)#011(?<answer_ttl>\d+)#011(?<answer_class>\w+)#011(?<answer_type>\w+)#011(?<answer_rdata>\S+)/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