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 = 'Jan 29 06:32:56 172.16.23.26 Jan 29 06:30:27 : CEF:0|ABCD Networks|NAC-VM-C|8.6.2.1203|-1|IP Address Update|1|rt=Jan 29 06:30:27 877 EST cat=EndStation src=10.10.14.58 smac=FA:39:71:6F:B3:43 shost=iPhone cs1Label=Physical<space>network<space>location cs1=AMNYPARU535A-FL37-VIP ROLE mobile msg=Adapter FA:39:71:6F:B3:43 IP Address changed from 10.10.14.53 to 10.10.14.58 Jan 28 21:22:51 172.16.23.26 Jan 28 21:20:24 : CEF:0|ABCD Networks|FortiNAC-VM-C|8.6.2.1203|-1|IP Address Update|1|rt=Jan 28 21:20:24 110 EST cat=EndStation src=10.3.38.61 smac=EA:19:49:37:10:73 shost=TsutomunoiPhone cs1Label=Physical<space>network<space>location cs1=APTOKARU535A-VIP ROLE mobile msg=Adapter EA:19:49:37:10:73 IP Address changed from 100.64.241.38 to 10.3.38.61 Jan 29 10:52:59 172.16.23.26 Jan 29 10:50:30 : CEF:0|ABCD Networks|NAC-VM-C|8.6.2.1203|303067011|Rogue Connected|1|rt=Jan 29 10:50:30 523 EST cat=EndStation smac=42:DE:D8:19:D2:69 cs1Label=Physical<space>network<space>location cs1=EUPARARU535A [10.2.32.198]-VIP ROLE registration msg=Rogue Host 42:DE:D8:19:D2:69 Connected to EUPARARU535A [10.2.32.198]-VIP ROLE registration.'; my $regex = qr/^(?:[^>\n]*>){2}\w+\s+\w+\d+\=(?P<cs_details>\w+[ -])/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