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

/
/
gi

Test String

Code Generator

Generated Code

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

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html