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

Code Generator

Language

Generated Code

import re regex = re.compile(r"[\r\n]+\s*\/\/.*TODO:+.*", flags=re.IGNORECASE) test_str = ("angular\n" " .module('mdKeyboard', ['material.components.bottomSheet'])\n" " .directive('mdKeyboard', MdKeyboardDirective)\n" " .provider('$mdKeyboard', MdKeyboardProvider);\n\n\n" "function MdKeyboardDirective($mdKeyboard, $mdBottomSheet, $timeout, $injector, $log) {\n" " return {\n" " restrict: 'A',\n" " require: '?ngModel',\n" " scope: {\n" " clickOutsideToClose: '=',\n" " preserveScope: '=',\n" " showInMobile: '='\n" " },\n" " link: function (scope, element, attrs, ngModelCtrl) {\n" " if (!ngModelCtrl) {\n" " return;\n" " }\n\n" " var bottomSheet;\n\n" " // Don't show virtual keyboard in mobile devices (default)\n" " //TODO: test detection and reimplement if neccessary\n" " //TODO: dissolve dependency to UAParser if possible / use angular or material utils\n" " if ($injector.has('UAParser')) {\n" " var UAParser = $injector.get('UAParser');\n" " var results = new UAParser().getResult();\n" " var isMobile = results.device.type === 'mobile' || results.device.type === 'tablet';\n" " isMobile = isMobile || (results.os && (results.os.name === 'Android'));\n" " isMobile = isMobile || (results.os && (results.os.name === 'iOS'));\n" " isMobile = isMobile || (results.os && (results.os.name === 'Windows Phone'));\n" " isMobile = isMobile || (results.os && (results.os.name === 'Windows Mobile'));\n" " if (isMobile && attrs.showInMobile !== true) {\n" " return;\n" " }\n" " }\n\n" " /*\n" " ngVirtualKeyboardService.attach(elements[0], scope.config, function() {\n" " $timeout(function() {\n" " ngModelCtrl.$setViewValue(elements[0].value);\n" " });\n" " });\n" " */\n\n" " $log.debug(attrs);\n" " element\n" " .bind('focus', showKeyboard)\n" " .bind('blur', hideKeyboard);\n\n" " function showKeyboard() {\n" " $log.info('showKeyboard');\n" " bottomSheet = $mdBottomSheet\n" " .show({\n" " template: '<md-bottom-sheet class=\"md-grid\" layout=\"column\" ng-cloak>{{keyboard}}</md-bottom-sheet>',\n" " controller: KeyboardController,\n" " clickOutsideToClose: attrs.clickOutsideToClose || false,\n" " preserveScope: attrs.preserveScope || true\n" " })\n" " .then(function () {\n\n" " });\n" " }\n\n" " function hideKeyboard() {\n" " $log.info('hideKeyboard');\n" " if (bottomSheet) {\n" " $mdBottomSheet.hide();\n" " delete bottomSheet;\n" " }\n" " }\n\n" " function KeyboardController($scope, $mdBottomSheet) {\n" " $scope.keyboard = 'TEST';\n" " }\n\n" " // open bottomsheet with keyboard on focus TODO: and without backdrop\n" " scope.keyboard = 'test';\n\n" " // When navigation force destroys an interimElement, then\n" " // listen and $destroy() that interim instance...\n" " scope.$on('$destroy', function () {\n" " $mdKeyboard.destroy();\n" " });\n" " }\n" " };\n" "}\n\n" "function MdKeyboardProvider($$interimElementProvider) {\n" " return $$interimElementProvider('$mdKeyboard')\n" " .setDefaults({\n" " options: keyboardDefaults\n" " });\n\n" " function keyboardDefaults() {\n" " return {\n" " themable: true,\n" " layout: defaultLayout\n" " };\n\n" " function defaultLayout() {\n" " // get default language\n" " return 'en-us';\n" " }\n" " }\n" "}\n") 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