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 = '29-09-2019, 20:50:21.355 15 QServer.exe LP5-BSS7-DSA 10.200.0.64 11784 Main 2 QServerService::RunLoop() Status(SERVICE_STOPPED); 29-09-2019, 20:50:21.355 1233215 QServer.exe LP5-BSS7-DSA 10.200.0.64 11784 Main 2 QServerService::RunLoop() Status(SERVICE_STOPPED); 29-09-2019, 21:31:06.424 245 QServer.exe QAG-MXG-CIAG02 10.5.3.144 7132 Trans_3 2 QKBSManager::HandleRequest: 248 01-10-2019, 22:23:36.400 5391 QClient.exe QAG-MXG-DCKR5 10.5.3.204 760 Main 8 104493 Path \'Domain:models/hbl%2Fdesignererror/LibSchedulerTM/UI/LibSchedulerTM/Component_FormGanttChartSchedulingCentre_TM/ModeledSecurities_FormGanttChartSchedulingCentre_TM.aus\': Reference \'/GanttChartSchedulingCentre_TM663/MenuOptimizer\' can not be resolved for \'ComponentSecurity\'. Please, check whether referenced element exists. 01-10-2019, 22:23:36.405 5392 QClient.exe QAG-MXG-DCKR5 10.5.3.204 760 Main 8 105603 Path \'Domain:models/hbl%2Fdesignererror/LibSchedulerTM/UI/LibSchedulerTM/Component_FormGanttChartSchedulingCentre_TM/ModeledSecurities_FormGanttChartSchedulingCentre_TM.aus\': \'ComponentSecurity\' can not be properly set to its parent \'ModeledSecurities FormGanttChartSchedulingCentre_TM\'.'; my $regex = qr/(\d{2}-\d{2}-\d{4}), (\d\d:\d\d:\d\d\.\+?\d+)\s*(\+?\d+)\s*(.*\.exe)\s*(.*?)\s*(\+?\d+\.\+?\d+\.\+?\d+.\+?\d+)\s*(\+?\d+)\s*([\w|\d]*)\s*(\d*)\s*(\d*)\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