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 = '14/May/2021:09:37:39 +0000 [715153] -> GET /content/ams/healthcheck/regent.html HTTP/1.1 14/May/2021:09:37:39 +0000 [2585977] <- 200 text/html;charset=UTF-8 6ms 14/May/2021:10:37:39 +0100 [1502141] -> GET /libs/granite/csrf/token.json HTTP/1.1 14/May/2021:09:37:39 +0000 [715152] <- 200 text/html;charset=UTF-8 6ms 14/May/2021:11:52:22 +0000 [11097977] -> GET /content/onehub_nfz/ru/ru/model-overview/caddy.html?tc=oa-[B]_[Caddy]_[All]_[None]_[BMM]_[RU]_[Eval]_Yandex_Search_AON_Paid_Search-Yandex-cpc-Search-banner&kw={PHRASE}&utm_source=yandex&utm_medium=cpc&utm_campaign=[B]_[Caddy]_[All]_[None]_[BMM]_[RU]_[Eval]_Yandex_Search_AON_Paid_Search&utm_term={PHRASE}&utm_content=s_{SRC}|cid_45783621|gid_{GBID}|aid_8728578416|pid_{PHRASE_EXPORT_ID}|rid_{PARAM126}|p_{POS}|pty_{PTYPE} HTTP/1.1 '; my $regex = qr/(?P<request_date>^[\w\/\:]+)\s+(?P<request_offset>[\d\+]+)\s+\[(?P<request_id>.+)\]\s+(?P<request_inout>[\-\>\<]+)\s+((?P<request_method>[GET|POST|HEAD|PUT|DELETE|CONNECT|OPTIONS|TRACE|PATCH]+)?\s+(?P<request_path>[^;][^;][a-zA-Z0-9\/\_\-\.\=\@\:\%\+\~\#\?\&\{\}\[\]\|]+)\s+(?P<request_protocol>.+)\s+|(?P<request_code>\d+)\s+(?P<request_filetype>.+)\s+(?P<request_duration>[\d\w]+)\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