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"(?<=\/)[^\/]*(?=\.)" test_str = ("src/profile/Admin.profile\n" "src/profile/Chatter External User.profile\n" "src/profile/Chatter Free User.profile\n" "src/profile/Chatter Moderator User.profile\n" "src/profile/Company Communities User.profile\n" "src/profile/ContractManager.profile\n" "src/profile/Guest License User.profile\n" "src/profile/High Volume Customer Portal User.profile\n" "src/profile/Integratie.profile\n" "src/profile/MarketingProfile.profile\n" "src/profile/OWS.profile\n" "src/profile/Photos Profile.profile\n" "src/profile/PostNL - Audit.profile\n" "src/profile/PostNL - Business gebruiker.profile\n" "src/profile/PostNL - Controlroom C%26S Aanmaker - CC.profile\n" "src/profile/PostNL - Controlroom C%26S Analist - CC.profile\n" "src/profile/PostNL - Controlroom C%26S Behandelaar - CC.profile\n" "src/profile/PostNL - DUB - CC.profile\n" "src/profile/PostNL - Directeur V%26B - CC.profile\n" "src/profile/PostNL - IT Servicedesk - CC.profile\n" "src/profile/PostNL - K%26K behandelaar.profile\n" "src/profile/PostNL - Klachten Behandelaar - CC.profile\n" "src/profile/PostNL - Klachten Inzage - CC.profile\n" "src/profile/PostNL - Netwerk Behandelaar.profile\n" "src/profile/PostNL - OBSB - CC.profile\n" "src/profile/PostNL - OBSB Beheerder - CC.profile\n" "src/profile/PostNL - OR Administrator - CC.profile\n" "src/profile/PostNL - Postbezorger Community - CC.profile\n" "src/profile/PostNL - Postbezorger Community Chatter - CC.profile\n" "src/profile/PostNL - Postbezorger Community Chauffeur - CC.profile\n" "src/profile/PostNL - Postbezorger Community Extern - CC.profile\n" "src/profile/PostNL - Postbezorger Community PB ZW - CC.profile\n" "src/profile/PostNL - Postbezorger Community Voorbereiden - CC.profile\n" "src/profile/PostNL - Procesmanager Bezorgen - CC.profile\n" "src/profile/PostNL - Procesmanager Voorbereiden - CC.profile\n" "src/profile/PostNL - Regiomanagers - CC.profile\n" "src/profile/PostNL - Service Centrum Medewerker.profile\n" "src/profile/PostNL - Teamleider - CC.profile\n" "src/profile/PostNL - Teamleider Voorbereiden - CC.profile\n" "src/profile/PostNL - Werkorder behandelaar - CC.profile\n" "src/profile/ReadOnly.profile\n" "src/profile/SolutionManager.profile\n" "src/profile/Standard.profile") 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