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 = '<134> id=FIREWALL_SYSLOG time="2019-03-21 12:30:24" fw=1.1.1.1 pri=6 c=1024 gcat=6 m=537 msg="Connection Closed" srcMac=aa:bb:cc:dd:ee:ff src=2.2.2.2:12345:X1 srcZone=LAN natSrc=3.3.3.3:54321 dstMac=gg:hh:ii:jj:kk:ll dst=4.4.4.4:443:X2 dstZone=WAN natDst=5.5.5.5:443 usr="Unknown" proto=tcp/https sent=1348 rcvd=8230 spkt=10 rpkt=9 cdur=2266 rule="(WAN->WAN)" app=49177 appName="HTTPS" n=55917537'; my $regex = qr/(?:id=(?<ID_Firewall>\w+) )(?:.*time="(?<timestamp>(?:[0-9]{4})-(?:[0-9]{2})-(?:[0-9]{2}) (?:[0-9]{2}):(?:[0-9]{2}):(?:[0-9]{2}))")(?: fw=(?<IP_Firewall>[[:graph:]]+))(?: pri=(?<Niveau>(?:[0-9]{1,2})))(?:.*m=(?<ID_Event>[[:graph:]]+))(?:.*?msg="(?<Description>[^"]+))(?:.*srcMac=(?<MAC_Source>[[:graph:]]+))?(?:.*src=(?<IP_Source>(?:[[:digit:]]+\.){3}(?:[[:digit:]]+))?)(?::(?<Port_Source>[[:digit:]]+)?)(?::(?<INT_Source>[[:graph:]]+))(?:.*srcZone=(?<Zone_Source>[[:graph:]]+))?(?:.*natSrc=(?<NAT_Source>(?:[[:digit:]]+\.){3}(?:[[:digit:]]+))?)?(?::(?<NAT_Port_Source>[[:digit:]]+)?)?(?:.*dstMac=(?<MAC_Destination>[[:graph:]]+))?(?:.*dst=(?<IP_Destination>(?:[[:digit:]]+\.){3}(?:[[:digit:]]+))?)(?::(?<Port_Destination>[[:digit:]]+)?)(?::(?<INT_Destination>[[:graph:]]+))(?:.*dstZone=(?<Zone_Destination>[[:graph:]]+))?(?:.*natDst=(?<NAT_Destination>(?:[[:digit:]]+\.){3}(?:[[:digit:]]+))?)?(?::(?<NAT_Port_Destination>[[:digit:]]+)?)?(?:.*usr="(?<Utilisateur>[^"]+))?(?:.*proto=(?<Protocole>[[:graph:]]+))?(?:.*rule="(?<Regle>[^"]+))?(?:.*appName="(?<Nom_Application>[^"]+))?(?:.*dstname=(?<Nom_Destination>[[:graph:]]+))?(?:.*arg=(?<Argument_DST>[[:graph:]]+))?(?:.*Category="(?<Categorie>[^"]+))?(?:.*note="(?<Note>[^"]+))?/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