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"(\w{3}\s\s\d{1,2} \d{2}:\d{2}:\d{2})\s(\S*)\s(\S*):\s\[(\S*)\]\s\[(\w\d{6})\]\s(\S*)\.(\w*):\s(.*)[\s|\s\[]({.*})" test_str = ("Feb 5 23:30:09 netoapi-06ae0d2a778f6d96c neto-ecommerce[21749]: [Self=1-5c5a1c7f-1417875ef90160804e31a159;Root=1-5c5a1c78-c849bf9b2a5aa92ee1ffd501] [N015185] app.ERROR: Entity of type 'Neto\\ShopBundle\\Entity\\Country' for IDs code() was not found [] {\"\"tags\"\":[\"\"sales_channels\"\"]}\"\n" "Feb 5 23:10:00 cpanel-0b75ea0f831a1a35a neto-ecommerce[4987]: [Self=1-5c5a17c8-1b0a7d58cd923b42ff5a7412;Root=1-5c5a17c8-5432af944896f7d093992b3a] [N008907] app.ERROR: Uncaught PHP Exception Symfony\\Component\\HttpKernel\\Exception\\AccessDeniedHttpException: \"\"Installation wizard is not supported for Amazon AU\"\" at /opt/release/Neto6.38.0/vendor/php/symfony/symfony/src/Symfony/Component/Security/Http/Firewall/ExceptionListener.php line 117 {\"\"exception\"\":\"\"[object] (Symfony\\\\Component\\\\HttpKernel\\\\Exception\\\\AccessDeniedHttpException(code: 0): Installation wizard is not supported for Amazon AU at /opt/release/Neto6.38.0/vendor/php/symfony/symfony/src/Symfony/Component/Security/Http/Firewall/ExceptionListener.php:117, Symfony\\\\Component\\\\Security\\\\Core\\\\Exception\\\\AccessDeniedException(code: 403): Installation wizard is not supported for Amazon AU at /opt/release/Neto6.38.0/vendor/php/symfony/symfony/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerTrait.php:379)\"\"} {\"\"tags\"\":[\"\"sales_channels\"\"]}\"\n" "Feb 5 21:35:06 netoapi-050acc5cb696746e7 neto-ecommerce[31278]: [Self=1-5c5a0188-c0db1f2809ade66c634f9576;Root=1-5c5a0185-b02bf3209835c7a4df7e5c2c] [N015185] app.ERROR: Entity of type 'Neto\\ShopBundle\\Entity\\Country' for IDs code() was not found [] {\"\"tags\"\":[\"\"sales_channels\"\"]}\"\n" "Feb 6 05:59:30 netoapi-07743f4e14561df22 neto-ecommerce[5407]: [Self=1-5c5a77c1-0019eb7067e6cc30180f9770;Root=1-5c5a77a7-2fa7f778122a1698c2a7e286] [N016687] app.CRITICAL: Uncaught PHP Exception Doctrine\\DBAL\\Exception\\DriverException: \"An exception occured in driver: SQLSTATE[HY000] [1203] User N016687_web already has more than 'max_user_connections' active connections\" at /opt/release/Neto6.38.0/vendor/php/doctrine/dbal/lib/Doctrine/DBAL/Driver/AbstractMySQLDriver.php line 115 {\"exception\":\"[object] (Doctrine\\\\DBAL\\\\Exception\\\\DriverException(code: 0): An exception occured in driver: SQLSTATE[HY000] [1203] User N016687_web already has more than 'max_user_connections' active connections at /opt/release/Neto6.38.0/vendor/php/doctrine/dbal/lib/Doctrine/DBAL/Driver/AbstractMySQLDriver.php:115, Doctrine\\\\DBAL\\\\Driver\\\\PDOException(code: 1203): SQLSTATE[HY000] [1203] User N016687_web already has more than 'max_user_connections' active connections at /opt/release/Neto6.38.0/vendor/php/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php:47, PDOException(code: 1203): SQLSTATE[HY000] [1203] User N016687_web already has more than 'max_user_connections' active connections at /opt/release/Neto6.38.0/vendor/php/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOConnection.php:43)\"} {\"tags\":[\"sales_channels\"]}") 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