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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"(\([\w\s].*[\w\s]\)|\(\)) =>", flags=re.MULTILINE | re.IGNORECASE) test_str = ("var MODULE = ((my, $, undefined) => {\n\n" " console.log('EXECUTION FROM LEGACY APP START ===>');\n\n" " // if private var defined in my module, use that\n" " // else create a private var\n" " var _private = my._private = my._private || {},\n" " _seal = my._seal = function seal(seal) {\n" " if (!seal) {\n" " return;\n" " }\n\n" " delete my._private;\n" " delete my._seal;\n" " console.log('SEALED');\n" " },\n" " _unseal = my._unseal = function unseal(unseal) {\n" " if (!unseal) {\n" " return;\n" " }\n\n" " my._seal = _seal;\n" " my._private = _private;\n" " console.log('UNSEALED');\n" " };\n\n" " var name = 'Tonny Frank';\n" " _private.name = 'This is a private name: ' + name;\n\n" " _private.reverse = function reverse(str) {\n" " return str.split('').reverse().join('');\n" " };\n\n" " if ($ === undefined) {\n" " console.log('jQuery not defined');\n" " return;\n" " }\n\n" " $(() => {\n" " var $h1 = $('.card').children('h1');\n" " $h1.html(_private.reverse($h1.html()));\n" " });\n\n" " console.log(my);\n" " my.myMethod = () => {\n" " console.log('MODULE myMethod Executed');\n" " $('.name').html('Abhisek ...');\n" " $('button').click(function (ev) {\n" " ev.preventDefault();\n" " console.log(this);\n" " $(this).html('Damn!');\n" " });\n" " };\n\n" " console.log('EXECUTION FROM LEGACY APP END <===');\n\n" " return my;\n" "})(MODULE || {}, this.jQuery);\n") subst = "function $1" 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