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

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?:\$|jQuery)\.mage\.__\((?s)[^'"]*?(['"])(.+?)(?<!\\)\1(?s).*?\)`) var str = `/** * Copyright © 2013-2017 Magento, Inc. All rights reserved. * See COPYING.txt for license details. */ define([ 'jquery', 'ko', 'module', '../template/renderer', 'mage/translate' ], function ($, ko, module, renderer) { 'use strict'; var locations = { 'legend': 'Caption for the fieldset element', 'label': 'Label for an input element.', 'button': 'Push button', 'a': 'Link label', 'b': 'Bold text', 'strong': 'Strong emphasized text', 'i': 'Italic text', 'em': 'Emphasized text', 'u': 'Underlined text', 'sup': 'Superscript text', 'sub': 'Subscript text', 'span': 'Span element', 'small': 'Smaller text', 'big': 'Bigger text', 'address': 'Contact information', 'blockquote': 'Long quotation', 'q': 'Short quotation', 'cite': 'Citation', 'caption': 'Table caption', 'abbr': 'Abbreviated phrase', 'acronym': 'An acronym', 'var': 'Variable part of a text', 'dfn': 'Term', 'strike': 'Strikethrough text', 'del': 'Deleted text', 'ins': 'Inserted text', 'h1': 'Heading level 1', 'h2': 'Heading level 2', 'h3': 'Heading level 3', 'h4': 'Heading level 4', 'h5': 'Heading level 5', 'h6': 'Heading level 6', 'center': 'Centered text', 'select': 'List options', 'img': 'Image', 'input': 'Form element' }, /** * Generates [data-translate] attribute's value * @param {Object} translationData * @param {String} location */ composeTranslateAttr = function (translationData, location) { var obj = [{ 'shown': translationData.shown, 'translated': translationData.translated, 'original': translationData.original, 'location': locations[location] || 'Text' }]; return JSON.stringify(obj); }, /** * Sets text for the element * @param {Object} el * @param {String} text */ setText = function (el, text) { $(el).text(text); }, /** * Sets [data-translate] attribute for the element * @param {Object} el - The element which is binded * @param {String} original - The original value of the element */ setTranslateProp = function (el, original) { var location = $(el).prop('tagName').toLowerCase(), translated = $.mage.__(original), translationData = { shown: translated, translated: translated, original: original }, translateAttr = composeTranslateAttr(translationData, location); $(el).attr('data-translate', translateAttr); setText(el, translationData.shown); }, /** * Checks if node represents ko virtual node (nodeType === 8, nodeName === '#comment'). * * @param {HTMLElement} node * @returns {Boolean} */ isVirtualElement = function (node) { return node.nodeType === 8; }, /** * Checks if it's real DOM element * in case of virtual element, returns span wrapper * @param {Object} el * @param {bool} isUpdate * @return {Object} el */ getRealElement = function (el, isUpdate) { if (isVirtualElement(el)) { if (isUpdate) { return $(el).next('span'); } return $('<span/>').insertAfter(el); } return el; }, /** * execute i18n binding * @param {Object} element * @param {Function} valueAccessor * @param {bool} isUpdate */ execute = function (element, valueAccessor, isUpdate) { var original = ko.unwrap(valueAccessor() || ''), el = getRealElement(element, isUpdate), inlineTranslation = (module.config() || {}).inlineTranslation; if (inlineTranslation) { setTranslateProp(el, original); } else { setText(el, $.mage.__(original)); } }; /** * i18n binding * @property {Function} init * @property {Function} update */ ko.bindingHandlers.i18n = { /** * init i18n binding * @param {Object} element * @param {Function} valueAccessor */ init: function (element, valueAccessor) { execute(element, valueAccessor); }, /** * update i18n binding * @param {Object} element * @param {Function} valueAccessor */ update: function (element, valueAccessor) { execute(element, valueAccessor, true); } }; ko.virtualElements.allowedBindings.i18n = true; renderer .addNode('translate', { binding: 'i18n' }) .addAttribute('translate', { binding: 'i18n' }); }); ` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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 Golang, please visit: https://golang.org/pkg/regexp/