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

/
/
g

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?<opening>\b(?<montage>[a-zA-Z]:[\/\\])|[\/\\][\/\\](?<!http:\/\/)(?<!https:\/\/)(?>[?.][\/\\](?:[^\/\\<>:\"|?\n\r ]+[\/\\])?(?&montage)?|(?!(?&montage)))|%\w+%[\/\\]?)(?:[^\/\\<>:\"|?\n\r ,'][^\/\\<>:\"|?\n\r]*(?<![ ,'])[\/\\])*(?:(?=[^\/\\<>:\"'|?\n\r;, ])(?:(?:[^\/\\<>:\"|?\n\r;, .](?: (?=[\w\-]))?(?:\*(?!= ))?(?!(?&montage)))+)?(?:\.\w+)*)|(?:'(?&opening)(?=.*'\W|.*'$)(?:[^\/\\<>:'\"|?\n\r]+(?:'(?=\w))?[\/\\]?)*')|\"(?&opening)(?=.*\")(?:[^\/\\<>:\"|?\n\r]+[\/\\]?)*\"" test_str = ("THIS IS SINGLE LINE VERSION\n" "to understand and edit it, go https://regex101.com/r/7o2fyy\n\n" "C:/testOk\\dot.Dirname/.nameFileBeginByDot first space after a dot in file name stop the match\n" "C:/testOk\\_.._AsDirName/../file name.ext1.ext2 first space after a dot stop the match\n" "start text don't match C:/testOk\\lastDir Or FileName WithDouble..dot stop the match\n" "C:/testOk\\lastDir Or FileName dot ended. stop the match like an end sentence. So, a last name with a space after a dot is not catch\n" "C:/testOk\\LastNameIs/DirName C:/testOk\\2Paths_ _separated/f.ext space after extention stop match\n" "C:/testOK\\Last_/_isNotmatched/fgfj.gjjb/uhloext/ and [ ,'] after '\\' stop match\n" "\\\\127.0.0.1/this', 'isOkInMidDirName\\butSimple',' stop match in last DirName or FileName\n" "\\\\.\\c:/this exotic path begining work\\and\\ space after '\\' stop the match\n" "\\\\?\\c:/this exotic path begining work too\\and \\space before '\\' stop the match too\n" "\\\\testOk/this' - 'is ok in dirName/and - in lastName.ext\n" "i:/dir/fileName with a .space before dot stop the match\n" "\\\\?\\server1\\e:\\utilities\\\\filecomparer\\ this double \\\\ is interpretated as new path\n\n\n" "@\"c:\\testOk\\double quote character is more permissive/ '' , ; .txt, .ext2\",\n" "@\"\\\\127.0.0.1\\c$\\temp\\t'est-file.txt, if end double quote is missing, we use unquote match\n" "@\"\\c:\\LOCALHOST\\c$\\ thisIsNotMatched\" \"temp\\test-file.txt\", quoted path must have a right opening to be matched\n" "@'\\\\.\\c:\\temp\\te'st-file.txt' simple quoted is ok \n" "'c:\\simpleQuoteInsideStill'Match\\but' stopMatch if next is space character,\n" "'c:\\simpleQuoteInsideStill'Match\\but\\'stopMatch if is fisrt character after \\\n" "'c:\\simpleQuoteInsideStill'Match\\but''stopMatch if he is double\n" "@\"\\\\?\\c:\\te ' mp\\est-file.txt\",\n" "@\"\\\\.\\UNC\\LOCALHOST\\c$\\temp\\test-file.txt\",\n" "@\"\\\\127.0.0.1\\c$\\temp\\test-file.txt\"\n\n" "/\\serverName\\mix/and\\still match\" double quote character stop match\n" "\\\\\\IfMoreThan2_\\_we take only the 2 lasts.ext first space after ext stop the match\n" "/testNotMatch/html\n" "/testNotMatch.html\n" "testNotMatch.html\n" "// -> this simple // or \\\\ is not matched, but this //isMatched !\n" "/ -> this simple / is not matched, and this /notMatchedToo\n" "b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"\n" "\"b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"\n" "\"\\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"\n\n" "error Message test:\n" "---------------------------\n" "Tentative d'accès à C:\\Users\\tpgz4017\\App - Data\\Local\\Temp\\tempShapeFile_CrossWave Calibration Zones - Atoll CrossWave Model.shx après sa fin.\n" "---------------------------\n\n" "local url path :\n" "file://C:/Users/Downloads/20220516_32289275_1049383.pdf\n" "urlPath :\n" "file://p-eco2.rd.fr/vol_H0037_01$/599/livraison/20220516_32289275_1049383.pdf\n\n" "c:\\temp\\test-file.txt\",\n" "\\\\127.0.0.1\\c$\\temp\\test-file.txt\",\n" "\\\\LOCALHOST\\c$\\ temp\\test-file.txt\",\n" "\\\\LOCALHOST\\c$ \\temp\\test-file.txt\",\n" "\\\\.\\c:\\temp\\t\\est-file.txt\",\n" "\\\\?\\c:\\temp\\test-file.txt\",\n" "\\\\.\\UNC\\LOCALHOST\\c$\\temp\\test-file.txt\",\n" "\\\\?\\UNC\\ServerName\\ temp\\test-file.txt\",\n" "\\\\127.0.0.1\\c$\\temp\\test -file.txt\"\n\n\n" "error Message test:\n" "Site0 / 3: - Warning . See log file 'C:\\ProgramData\\InfoVista\\Planet 7.4\\7.4\\RPE\\Log\\Plugins\\Universal_Model_masked\\log_Universal_Model.txt' for details\n\n" "C:/test\\gvk.hv/fgfj.gjjb/uhloext : some random text\n\n" "\\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau hgtfhyt \"C:/te-st.html\" \"C:/te-st.html\" gd\"dhbcsk \"C:/te/dsst.ikpo fdsf \"C:\\test\" \"C:// test.html\" gd\n" "\"//te s t/e, llo.html \n" "C:/test\\f/uhlo/. \n" "C://te?st.html\n" "b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"\n" "; dfsdf \"\\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"\n" "; dfsdf \"\\\\\n" "\"\\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Custom Data\"Haguenau_Building.tab : Data format of \\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau Building.* C: is invalid\n" "Haguenau_Building.tab : Data format of \\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo NetAct Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau Building.TAB, is invalid\n" "Haguenau_Building.tab : Data format of \\\\b-renice\\sauvegardes\\B-HIER\\GEO\\Geo_NetAct_Atoll_Planet\\UR_Est\\Polygon\\Haguenau\\Building\\Haguenau Buildi*.*ng.*, is invalid\n" "C:/test/../hjgbkl C:/test/../hjgbkl.gfgdfgrdgfdgr C:/test/../hjgbkl\n" "C:/test.html\n" "C://test/ .h/hel,lo.html//test/./hello.html\n" "C:/test//hello.html\n" "//test\n" "//hello.html\n" "/test\n" "\"%tmp%/fsdfs\"\n" "%tmp%/fsdfs\n" "ERROR 8/31/2021 - 6:45:39 PM HighResClutter .RasterFile : \\\\b-ren ice\\sauv egardes\\B-HIER\\GEO%dsq%\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil : Le fichier spécifié est introuvable. \n" "\\\\b-ren ice\\sauv egardes\\..\\B-HIER\\GEO\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil C:\\b-ren ice\\sauv egardes\\B-HIER\\GEO\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil \\\\b-ren ice\\sauv egardes\\B-HIER\\GEO\\NewJersey_NewYork\\DTM\\DTM\\CENTRAL_JER SE.Y_New_York_2 m_Z18N_0_DTM_02_06.bil. \n" "//test.html\n" "\\\\10.1.1.107\n" "//10.1.1.107/test.html\n" "//10.1.1.107/te st/hello.html\n" "//10.1.1.107/test/hello\n" "//test/hello.txt\n" "//test/hello.txt.\n\n" "\\\\.\\UNC\\Server\\Share\\Test\\Foo.txt \n" "\\\\?\\UNC\\Server\\Share\\Test\\Foo.txt\n\n" "Pour les chemins UNC de périphérique, la partie serveur/partage forme le volume. Par exemple, dans \\\\?\\server1\\e:\\utilities\\filecomparer\\ , la partie serveur/partage est server1\\utilities . Ceci est important quand\n" "'\\\\127.0.0.1\\c$\\temp\\test-fi'le.txt'") matches = re.finditer(regex, test_str) 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