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

Substitution
Processing...

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?|(\[[\"]?.+?[\"]?\])(=>)\R\s*|(?<=\(0\) )(\{)\R\s*(\}))") test_str = ("object(Symfony\\Component\\HttpFoundation\\Request)#250 (21) {\n" " [\"attributes\"]=>\n" " object(Symfony\\Component\\HttpFoundation\\ParameterBag)#253 (1) {\n" " [\"parameters\":protected]=>\n" " array(5) {\n" " [\"_controller\"]=>\n" " object(Closure)#239 (2) {\n" " [\"static\"]=>\n" " array(1) {\n" " [\"app\"]=>\n" " object(Silex\\Application)#14 (8) {\n" " [\"providers\":protected]=>\n" " array(5) {\n" " [0]=>\n" " object(Silex\\Provider\\HttpKernelServiceProvider)#17 (0) {\n" " }\n" " [1]=>\n" " object(Silex\\Provider\\RoutingServiceProvider)#26 (0) {\n" " }\n" " [2]=>\n" " object(Silex\\Provider\\ExceptionHandlerServiceProvider)#36 (0) {\n" " }\n" " [3]=>\n" " object(Silex\\Provider\\TwigServiceProvider)#38 (0) {\n" " }\n" " [4]=>\n" " object(Euskadi31\\Silex\\Provider\\CorsServiceProvider)#54 (0) {\n" " }\n" " }\n" " [\"booted\":protected]=>\n" " bool(true)\n" " [\"values\":\"Pimple\\Container\":private]=>\n" " array(37) {\n" " [\"request.http_port\"]=>\n" " int(80)\n" " [\"request.https_port\"]=>\n" " int(443)\n" " [\"debug\"]=>\n" " bool(true)\n" " [\"charset\"]=>\n" " string(5) \"UTF-8\"\n" " [\"logger\"]=>\n" " NULL\n" " [\"resolver\"]=>\n" " object(Symfony\\Component\\HttpKernel\\Controller\\ControllerResolver)#307 (1) {\n" " [\"logger\":\"Symfony\\Component\\HttpKernel\\Controller\\ControllerResolver\":private]=>\n" " NULL\n" " }\n" " [\"argument_metadata_factory\"]=>\n" " object(Symfony\\Component\\HttpKernel\\ControllerMetadata\\ArgumentMetadataFactory)#301 (0) {\n" " }\n" " [\"argument_value_resolvers\"]=>\n" " array(5) {\n" " [0]=>\n" " object(Silex\\AppArgumentValueResolver)#298 (1) {\n" " [\"app\":\"Silex\\AppArgumentValueResolver\":private]=>\n" " *RECURSION*\n" " }\n" " [1]=>\n" " object(Symfony\\Component\\HttpKernel\\Controller\\ArgumentResolver\\RequestAttributeValueResolver)#295 (0) {\n" " }\n" " [2]=>\n" " object(Symfony\\Component\\HttpKernel\\Controller\\ArgumentResolver\\RequestValueResolver)#292 (0) {\n" " }\n" " [3]=>\n" " object(Symfony\\Component\\HttpKernel\\Controller\\ArgumentResolver\\DefaultValueResolver)#289 (0) {\n" " }\n" " [4]=>\n" " object(Symfony\\Component\\HttpKernel\\Controller\\ArgumentResolver\\VariadicValueResolver)#286 (0) {\n" " }\n" " }") subst = "\\1 \\2" result = regex.sub(subst, test_str) if result: print(result)

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