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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"^\[(?<time>[^\]]*)\] (?<level>[^:]*):\s+(?<reason>.+?) \/[^\/]*\/(?<repo>[^\/]*)\/[^\/]*\/(?<release>[0-9]*)\/(?<file>[^\s|:]*)[^0-9]*(?<line>[0-9]*)", flags=re.MULTILINE) test_str = ("[21-Feb-2019 10:24:23 Europe/Berlin] PHP Warning: SimpleXMLElement::__construct(): 'hostel','other_accommodation','other_accommodation','other_accommodation'), \"/> in /srv/hometogo_import/releases/20190221091925/src/Htg/Backend/StandardFeedBundle/Validators/ObjectValidator.php on line 133\n" "[21-Feb-2019 10:24:23 Europe/Berlin] PHP Warning: SimpleXMLElement::__construct(): ^ in /srv/hometogo_import/releases/20190221091925/src/Htg/Backend/StandardFeedBundle/Validators/ObjectValidator.php on line 133\n" "[21-Feb-2019 10:23:45 Europe/Berlin] PHP Notice: Undefined index: es_ES in /srv/hometogo_import/releases/20190221071657/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 10:24:23 Europe/Berlin] PHP Warning: SimpleXMLElement::__construct(): Entity: line 1: parser error : Extra content at the end of the document in /srv/hometogo_import/releases/20190221091925/src/Htg/Backend/StandardFeedBundle/Validators/ObjectValidator.php on line 133\n" "[21-Feb-2019 10:35:53 Europe/Berlin] PHP Notice: Undefined index: en_US in /srv/hometogo_import/releases/20190221071657/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 10:35:53 Europe/Berlin] PHP Notice: Undefined index: es_ES in /srv/hometogo_import/releases/20190221071657/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:43:05 Europe/Berlin] PHP Warning: PDOStatement::execute(): MySQL server has gone away in /srv/hometogo_import/releases/20190221082132/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php on line 105\n" "[21-Feb-2019 09:43:05 Europe/Berlin] PHP Warning: PDOStatement::execute(): Error reading result set's header in /srv/hometogo_import/releases/20190221082132/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php on line 105\n" "[21-Feb-2019 09:10:25 Europe/Berlin] PHP Notice: Undefined index: en_US in /srv/hometogo_import/releases/20190220180846/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:10:25 Europe/Berlin] PHP Notice: Undefined index: es_ES in /srv/hometogo_import/releases/20190220180846/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:10:30 Europe/Berlin] PHP Notice: Undefined index: en_US in /srv/hometogo_import/releases/20190221071657/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:10:30 Europe/Berlin] PHP Notice: Undefined index: es_ES in /srv/hometogo_import/releases/20190221071657/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:10:42 Europe/Berlin] PHP Fatal error: Uncaught RuntimeException: Process interrupted in /srv/hometogo_import/releases/20190221080147/src/Htg/Backend/KafkaBundle/Command/SinkToBufferCommand.php:193\n" "Stack trace:\n" "#0 [internal function]: Htg\\Backend\\KafkaBundle\\Command\\SinkToBufferCommand->processEnd()\n" "#1 {main}\n" " thrown in /srv/hometogo_import/releases/20190221080147/src/Htg/Backend/KafkaBundle/Command/SinkToBufferCommand.php on line 193\n" "[21-Feb-2019 09:10:42 Europe/Berlin] PHP Notice: Undefined index: en_US in /srv/hometogo_import/releases/20190220180846/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:10:42 Europe/Berlin] PHP Notice: Undefined index: es_ES in /srv/hometogo_import/releases/20190220180846/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:10:42 Europe/Berlin] PHP Warning: PDO::query(): MySQL server has gone away in /srv/hometogo_import/releases/20190221080147/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php on line 104\n" "[21-Feb-2019 09:10:42 Europe/Berlin] PHP Warning: PDO::query(): Error reading result set's header in /srv/hometogo_import/releases/20190221080147/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php on line 104\n" "[21-Feb-2019 09:11:54 Europe/Berlin] PHP Notice: Undefined index: en_US in /srv/hometogo_import/releases/20190221071657/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:05:20 Europe/Berlin] PHP Warning: call_user_func() expects parameter 1 to be a valid callback, no array or string given in /srv/hometogo_import/releases/20190221071657/src/Vrt/AggregatorBundle/Writer/Runner/Json.php on line 57\n" "[21-Feb-2019 09:05:30 Europe/Berlin] PHP Notice: Undefined index: en_US in /srv/hometogo_import/releases/20190220180846/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:05:30 Europe/Berlin] PHP Notice: Undefined index: es_ES in /srv/hometogo_import/releases/20190220180846/vendor/hometogo/data-model/src/Model/DestinationModel.php on line 358\n" "[21-Feb-2019 09:07:40 Europe/Berlin] PHP Warning: imagecreatefromstring(): Data is not in a recognized format in /srv/hometogo_image/releases/20181119092803/src/Htg/Transform/TransformationManager.php on line 159") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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