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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(\(loggingInfo\)|\(beneLoggingInfo\)) - (?<vendorinfo>[^|]*)\|(?<login>[^|]*)\|(?<action>[^|]*)\|(?<timeStamp>[^\|]*)\|(?<tag2>[^\|]*)\|(?<tag6>[^\|]*)\|(?<tag7>[^\|]*)\|(?<tag8>[^\|]*)\|(?<tag9>[^\|]*)\|(?<tag10>[^\|]*)\|(?<tag11>[^\|]*)\|" test_str = ("18 Jul 2018 09:05:31,068 INFO (loggingInfo) - Auto CRM|ppope|ApplicationLogin|Wed Jul 18 09:05:31 CDT 2018|CSR agent successfully logged in||Successful||||NA|\n\n" "22 Oct 2018 08:36:41,164 INFO (beneLoggingInfo) - Beneficiary Administration|TESTWHBENE|APPLICATION LOGIN|Mon Oct 22 08:36:41 CDT 2018|User successfully logged in for Client = 070||SUCCESSFUL||||NA|\n\n" "22 Oct 2018 00:43:23,845 INFO (loggingInfo) - Inquiry Application|TUSER4444|APPLICATION LOGIN|Mon Oct 22 00:43:23 CDT 2018|User successfully logged in for Client : 580||SUCCESSFUL||||NA|\n\n" "01 Oct 2018 09:29:33,508 INFO (loggingInfo) - ISIS PersonalPlan|TESTOMAR|APPLICATION LOGIN|Mon Oct 01 09:29:33 CDT 2018|User successfully logged in for Client : 002||SUCCESSFUL||||NA|\n\n" "24 Oct 2018 13:46:07,647 INFO (loggingInfo) - Web-Billing|egunderson| User Authentication|10/24/2018 01:46:07 PM| User Authentication|NA|True| NA| NA| NA| NA|\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