prism-core.js

/// <reference lib="WebWorker"/>

var _self = (typeof window !== 'undefined')
	? window   // if in browser
	: (
		(typeof WorkerGlobalScope !== 'undefined' && self instanceof WorkerGlobalScope)
			? self // if in worker
			: {}   // if in node js
	);

/**
 * Prism: Lightweight, robust, elegant syntax highlighting
 *
 * @license MIT <https://opensource.org/licenses/MIT>
 * @author Lea Verou <https://lea.verou.me>
 * @namespace
 * @public
 */
var Prism = (function (_self) {

	// Private helper vars
	var lang = /\blang(?:uage)?-([\w-]+)\b/i;
	var uniqueId = 0;

	// The grammar object for plaintext
	var plainTextGrammar = {};


	var _ = {
		/**
		 * By default, Prism will attempt to highlight all code elements (by calling {@link Prism.highlightAll}) on the
		 * current page after the page finished loading. This might be a problem if e.g. you wanted to asynchronously load
		 * additional languages or plugins yourself.
		 *
		 * By setting this value to `true`, Prism will not automatically highlight all code elements on the page.
		 *
		 * You obviously have to change this value before the automatic highlighting started. To do this, you can add an
		 * empty Prism object into the global scope before loading the Prism script like this:
		 *
		 * ```js
		 * window.Prism = window.Prism || {};
		 * Prism.manual = true;
		 * // add a new <script> to load Prism's script
		 * ```
		 *
		 * @default false
		 * @type {boolean}
		 * @memberof Prism
		 * @public
		 */
		manual: _self.Prism && _self.Prism.manual,
		/**
		 * By default, if Prism is in a web worker, it assumes that it is in a worker it created itself, so it uses
		 * `addEventListener` to communicate with its parent instance. However, if you're using Prism manually in your
		 * own worker, you don't want it to do this.
		 *
		 * By setting this value to `true`, Prism will not add its own listeners to the worker.
		 *
		 * You obviously have to change this value before Prism executes. To do this, you can add an
		 * empty Prism object into the global scope before loading the Prism script like this:
		 *
		 * ```js
		 * window.Prism = window.Prism || {};
		 * Prism.disableWorkerMessageHandler = true;
		 * // Load Prism's script
		 * ```
		 *
		 * @default false
		 * @type {boolean}
		 * @memberof Prism
		 * @public
		 */
		disableWorkerMessageHandler: _self.Prism && _self.Prism.disableWorkerMessageHandler,

		/**
		 * A namespace for utility methods.
		 *
		 * All function in this namespace that are not explicitly marked as _public_ are for __internal use only__ and may
		 * change or disappear at any time.
		 *
		 * @namespace
		 * @memberof Prism
		 */
		util: {
			encode: function encode(tokens) {
				if (tokens instanceof Token) {
					return new Token(tokens.type, encode(tokens.content), tokens.alias);
				} else if (Array.isArray(tokens)) {
					return tokens.map(encode);
				} else {
					return tokens.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/\u00a0/g, ' ');
				}
			},

			/**
			 * Returns the name of the type of the given value.
			 *
			 * @param {any} o
			 * @returns {string}
			 * @example
			 * type(null)      === 'Null'
			 * type(undefined) === 'Undefined'
			 * type(123)       === 'Number'
			 * type('foo')     === 'String'
			 * type(true)      === 'Boolean'
			 * type([1, 2])    === 'Array'
			 * type({})        === 'Object'
			 * type(String)    === 'Function'
			 * type(/abc+/)    === 'RegExp'
			 */
			type: function (o) {
				return Object.prototype.toString.call(o).slice(8, -1);
			},

			/**
			 * Returns a unique number for the given object. Later calls will still return the same number.
			 *
			 * @param {Object} obj
			 * @returns {number}
			 */
			objId: function (obj) {
				if (!obj['__id']) {
					Object.defineProperty(obj, '__id', { value: ++uniqueId });
				}
				return obj['__id'];
			},

			/**
			 * Creates a deep clone of the given object.
			 *
			 * The main intended use of this function is to clone language definitions.
			 *
			 * @param {T} o
			 * @param {Record<number, any>} [visited]
			 * @returns {T}
			 * @template T
			 */
			clone: function deepClone(o, visited) {
				visited = visited || {};

				var clone; var id;
				switch (_.util.type(o)) {
					case 'Object':
						id = _.util.objId(o);
						if (visited[id]) {
							return visited[id];
						}
						clone = /** @type {Record<string, any>} */ ({});
						visited[id] = clone;

						for (var key in o) {
							if (o.hasOwnProperty(key)) {
								clone[key] = deepClone(o[key], visited);
							}
						}

						return /** @type {any} */ (clone);

					case 'Array':
						id = _.util.objId(o);
						if (visited[id]) {
							return visited[id];
						}
						clone = [];
						visited[id] = clone;

						(/** @type {Array} */(/** @type {any} */(o))).forEach(function (v, i) {
							clone[i] = deepClone(v, visited);
						});

						return /** @type {any} */ (clone);

					default:
						return o;
				}
			},

			/**
			 * Returns the Prism language of the given element set by a `language-xxxx` or `lang-xxxx` class.
			 *
			 * If no language is set for the element or the element is `null` or `undefined`, `none` will be returned.
			 *
			 * @param {Element} element
			 * @returns {string}
			 */
			getLanguage: function (element) {
				while (element && !lang.test(element.className)) {
					element = element.parentElement;
				}
				if (element) {
					return (element.className.match(lang) || [, 'none'])[1].toLowerCase();
				}
				return 'none';
			},

			/**
			 * Returns the script element that is currently executing.
			 *
			 * This does __not__ work for line script element.
			 *
			 * @returns {HTMLScriptElement | null}
			 */
			currentScript: function () {
				if (typeof document === 'undefined') {
					return null;
				}
				if ('currentScript' in document && 1 < 2 /* hack to trip TS' flow analysis */) {
					return /** @type {any} */ (document.currentScript);
				}

				// IE11 workaround
				// we'll get the src of the current script by parsing IE11's error stack trace
				// this will not work for inline scripts

				try {
					throw new Error();
				} catch (err) {
					// Get file src url from stack. Specifically works with the format of stack traces in IE.
					// A stack will look like this:
					//
					// Error
					//    at _.util.currentScript (http://localhost/components/prism-core.js:119:5)
					//    at Global code (http://localhost/components/prism-core.js:606:1)

					var src = (/at [^(\r\n]*\((.*):[^:]+:[^:]+\)$/i.exec(err.stack) || [])[1];
					if (src) {
						var scripts = document.getElementsByTagName('script');
						for (var i in scripts) {
							if (scripts[i].src == src) {
								return scripts[i];
							}
						}
					}
					return null;
				}
			},

			/**
			 * Returns whether a given class is active for `element`.
			 *
			 * The class can be activated if `element` or one of its ancestors has the given class and it can be deactivated
			 * if `element` or one of its ancestors has the negated version of the given class. The _negated version_ of the
			 * given class is just the given class with a `no-` prefix.
			 *
			 * Whether the class is active is determined by the closest ancestor of `element` (where `element` itself is
			 * closest ancestor) that has the given class or the negated version of it. If neither `element` nor any of its
			 * ancestors have the given class or the negated version of it, then the default activation will be returned.
			 *
			 * In the paradoxical situation where the closest ancestor contains __both__ the given class and the negated
			 * version of it, the class is considered active.
			 *
			 * @param {Element} element
			 * @param {string} className
			 * @param {boolean} [defaultActivation=false]
			 * @returns {boolean}
			 */
			isActive: function (element, className, defaultActivation) {
				var no = 'no-' + className;

				while (element) {
					var classList = element.classList;
					if (classList.contains(className)) {
						return true;
					}
					if (classList.contains(no)) {
						return false;
					}
					element = element.parentElement;
				}
				return !!defaultActivation;
			}
		},

		/**
		 * This namespace contains all currently loaded languages and the some helper functions to create and modify languages.
		 *
		 * @namespace
		 * @memberof Prism
		 * @public
		 */
		languages: {
			/**
			 * The grammar for plain, unformatted text.
			 */
			plain: plainTextGrammar,
			plaintext: plainTextGrammar,
			text: plainTextGrammar,
			txt: plainTextGrammar,

			/**
			 * Creates a deep copy of the language with the given id and appends the given tokens.
			 *
			 * If a token in `redef` also appears in the copied language, then the existing token in the copied language
			 * will be overwritten at its original position.
			 *
			 * ## Best practices
			 *
			 * Since the position of overwriting tokens (token in `redef` that overwrite tokens in the copied language)
			 * doesn't matter, they can technically be in any order. However, this can be confusing to others that trying to
			 * understand the language definition because, normally, the order of tokens matters in Prism grammars.
			 *
			 * Therefore, it is encouraged to order overwriting tokens according to the positions of the overwritten tokens.
			 * Furthermore, all non-overwriting tokens should be placed after the overwriting ones.
			 *
			 * @param {string} id The id of the language to extend. This has to be a key in `Prism.languages`.
			 * @param {Grammar} redef The new tokens to append.
			 * @returns {Grammar} The new language created.
			 * @public
			 * @example
			 * Prism.languages['css-with-colors'] = Prism.languages.extend('css', {
			 *     // Prism.languages.css already has a 'comment' token, so this token will overwrite CSS' 'comment' token
			 *     // at its original position
			 *     'comment': { ... },
			 *     // CSS doesn't have a 'color' token, so this token will be appended
			 *     'color': /\b(?:red|green|blue)\b/
			 * });
			 */
			extend: function (id, redef) {
				var lang = _.util.clone(_.languages[id]);

				for (var key in redef) {
					lang[key] = redef[key];
				}

				return lang;
			},

			/**
			 * Inserts tokens _before_ another token in a language definition or any other grammar.
			 *
			 * ## Usage
			 *
			 * This helper method makes it easy to modify existing languages. For example, the CSS language definition
			 * not only defines CSS highlighting for CSS documents, but also needs to define highlighting for CSS embedded
			 * in HTML through `<style>` elements. To do this, it needs to modify `Prism.languages.markup` and add the
			 * appropriate tokens. However, `Prism.languages.markup` is a regular JavaScript object literal, so if you do
			 * this:
			 *
			 * ```js
			 * Prism.languages.markup.style = {
			 *     // token
			 * };
			 * ```
			 *
			 * then the `style` token will be added (and processed) at the end. `insertBefore` allows you to insert tokens
			 * before existing tokens. For the CSS example above, you would use it like this:
			 *
			 * ```js
			 * Prism.languages.insertBefore('markup', 'cdata', {
			 *     'style': {
			 *         // token
			 *     }
			 * });
			 * ```
			 *
			 * ## Special cases
			 *
			 * If the grammars of `inside` and `insert` have tokens with the same name, the tokens in `inside`'s grammar
			 * will be ignored.
			 *
			 * This behavior can be used to insert tokens after `before`:
			 *
			 * ```js
			 * Prism.languages.insertBefore('markup', 'comment', {
			 *     'comment': Prism.languages.markup.comment,
			 *     // tokens after 'comment'
			 * });
			 * ```
			 *
			 * ## Limitations
			 *
			 * The main problem `insertBefore` has to solve is iteration order. Since ES2015, the iteration order for object
			 * properties is guaranteed to be the insertion order (except for integer keys) but some browsers behave
			 * differently when keys are deleted and re-inserted. So `insertBefore` can't be implemented by temporarily
			 * deleting properties which is necessary to insert at arbitrary positions.
			 *
			 * To solve this problem, `insertBefore` doesn't actually insert the given tokens into the target object.
			 * Instead, it will create a new object and replace all references to the target object with the new one. This
			 * can be done without temporarily deleting properties, so the iteration order is well-defined.
			 *
			 * However, only references that can be reached from `Prism.languages` or `insert` will be replaced. I.e. if
			 * you hold the target object in a variable, then the value of the variable will not change.
			 *
			 * ```js
			 * var oldMarkup = Prism.languages.markup;
			 * var newMarkup = Prism.languages.insertBefore('markup', 'comment', { ... });
			 *
			 * assert(oldMarkup !== Prism.languages.markup);
			 * assert(newMarkup === Prism.languages.markup);
			 * ```
			 *
			 * @param {string} inside The property of `root` (e.g. a language id in `Prism.languages`) that contains the
			 * object to be modified.
			 * @param {string} before The key to insert before.
			 * @param {Grammar} insert An object containing the key-value pairs to be inserted.
			 * @param {Object<string, any>} [root] The object containing `inside`, i.e. the object that contains the
			 * object to be modified.
			 *
			 * Defaults to `Prism.languages`.
			 * @returns {Grammar} The new grammar object.
			 * @public
			 */
			insertBefore: function (inside, before, insert, root) {
				root = root || /** @type {any} */ (_.languages);
				var grammar = root[inside];
				/** @type {Grammar} */
				var ret = {};

				for (var token in grammar) {
					if (grammar.hasOwnProperty(token)) {

						if (token == before) {
							for (var newToken in insert) {
								if (insert.hasOwnProperty(newToken)) {
									ret[newToken] = insert[newToken];
								}
							}
						}

						// Do not insert token which also occur in insert. See #1525
						if (!insert.hasOwnProperty(token)) {
							ret[token] = grammar[token];
						}
					}
				}

				var old = root[inside];
				root[inside] = ret;

				// Update references in other language definitions
				_.languages.DFS(_.languages, function (key, value) {
					if (value === old && key != inside) {
						this[key] = ret;
					}
				});

				return ret;
			},

			// Traverse a language definition with Depth First Search
			DFS: function DFS(o, callback, type, visited) {
				visited = visited || {};

				var objId = _.util.objId;

				for (var i in o) {
					if (o.hasOwnProperty(i)) {
						callback.call(o, i, o[i], type || i);

						var property = o[i];
						var propertyType = _.util.type(property);

						if (propertyType === 'Object' && !visited[objId(property)]) {
							visited[objId(property)] = true;
							DFS(property, callback, null, visited);
						} else if (propertyType === 'Array' && !visited[objId(property)]) {
							visited[objId(property)] = true;
							DFS(property, callback, i, visited);
						}
					}
				}
			}
		},

		plugins: {},

		/**
		 * This is the most high-level function in Prism’s API.
		 * It fetches all the elements that have a `.language-xxxx` class and then calls {@link Prism.highlightElement} on
		 * each one of them.
		 *
		 * This is equivalent to `Prism.highlightAllUnder(document, async, callback)`.
		 *
		 * @param {boolean} [async=false] Same as in {@link Prism.highlightAllUnder}.
		 * @param {HighlightCallback} [callback] Same as in {@link Prism.highlightAllUnder}.
		 * @memberof Prism
		 * @public
		 */
		highlightAll: function (async, callback) {
			_.highlightAllUnder(document, async, callback);
		},

		/**
		 * Fetches all the descendants of `container` that have a `.language-xxxx` class and then calls
		 * {@link Prism.highlightElement} on each one of them.
		 *
		 * The following hooks will be run:
		 * 1. `before-highlightall`
		 * 2. `before-all-elements-highlight`
		 * 3. All hooks of {@link Prism.highlightElement} for each element.
		 *
		 * @param {ParentNode} container The root element, whose descendants that have a `.language-xxxx` class will be highlighted.
		 * @param {boolean} [async=false] Whether each element is to be highlighted asynchronously using Web Workers.
		 * @param {HighlightCallback} [callback] An optional callback to be invoked on each element after its highlighting is done.
		 * @memberof Prism
		 * @public
		 */
		highlightAllUnder: function (container, async, callback) {
			var env = {
				callback: callback,
				container: container,
				selector: 'code[class*="language-"], [class*="language-"] code, code[class*="lang-"], [class*="lang-"] code'
			};

			_.hooks.run('before-highlightall', env);

			env.elements = Array.prototype.slice.apply(env.container.querySelectorAll(env.selector));

			_.hooks.run('before-all-elements-highlight', env);

			for (var i = 0, element; (element = env.elements[i++]);) {
				_.highlightElement(element, async === true, env.callback);
			}
		},

		/**
		 * Highlights the code inside a single element.
		 *
		 * The following hooks will be run:
		 * 1. `before-sanity-check`
		 * 2. `before-highlight`
		 * 3. All hooks of {@link Prism.highlight}. These hooks will be run by an asynchronous worker if `async` is `true`.
		 * 4. `before-insert`
		 * 5. `after-highlight`
		 * 6. `complete`
		 *
		 * Some the above hooks will be skipped if the element doesn't contain any text or there is no grammar loaded for
		 * the element's language.
		 *
		 * @param {Element} element The element containing the code.
		 * It must have a class of `language-xxxx` to be processed, where `xxxx` is a valid language identifier.
		 * @param {boolean} [async=false] Whether the element is to be highlighted asynchronously using Web Workers
		 * to improve performance and avoid blocking the UI when highlighting very large chunks of code. This option is
		 * [disabled by default](https://prismjs.com/faq.html#why-is-asynchronous-highlighting-disabled-by-default).
		 *
		 * Note: All language definitions required to highlight the code must be included in the main `prism.js` file for
		 * asynchronous highlighting to work. You can build your own bundle on the
		 * [Download page](https://prismjs.com/download.html).
		 * @param {HighlightCallback} [callback] An optional callback to be invoked after the highlighting is done.
		 * Mostly useful when `async` is `true`, since in that case, the highlighting is done asynchronously.
		 * @memberof Prism
		 * @public
		 */
		highlightElement: function (element, async, callback) {
			// Find language
			var language = _.util.getLanguage(element);
			var grammar = _.languages[language];

			// Set language on the element, if not present
			element.className = element.className.replace(lang, '').replace(/\s+/g, ' ') + ' language-' + language;

			// Set language on the parent, for styling
			var parent = element.parentElement;
			if (parent && parent.nodeName.toLowerCase() === 'pre') {
				parent.className = parent.className.replace(lang, '').replace(/\s+/g, ' ') + ' language-' + language;
			}

			var code = element.textContent;

			var env = {
				element: element,
				language: language,
				grammar: grammar,
				code: code
			};

			function insertHighlightedCode(highlightedCode) {
				env.highlightedCode = highlightedCode;

				_.hooks.run('before-insert', env);

				env.element.innerHTML = env.highlightedCode;

				_.hooks.run('after-highlight', env);
				_.hooks.run('complete', env);
				callback && callback.call(env.element);
			}

			_.hooks.run('before-sanity-check', env);

			// plugins may change/add the parent/element
			parent = env.element.parentElement;
			if (parent && parent.nodeName.toLowerCase() === 'pre' && !parent.hasAttribute('tabindex')) {
				parent.setAttribute('tabindex', '0');
			}

			if (!env.code) {
				_.hooks.run('complete', env);
				callback && callback.call(env.element);
				return;
			}

			_.hooks.run('before-highlight', env);

			if (!env.grammar) {
				insertHighlightedCode(_.util.encode(env.code));
				return;
			}

			if (async && _self.Worker) {
				var worker = new Worker(_.filename);

				worker.onmessage = function (evt) {
					insertHighlightedCode(evt.data);
				};

				worker.postMessage(JSON.stringify({
					language: env.language,
					code: env.code,
					immediateClose: true
				}));
			} else {
				insertHighlightedCode(_.highlight(env.code, env.grammar, env.language));
			}
		},

		/**
		 * Low-level function, only use if you know what you’re doing. It accepts a string of text as input
		 * and the language definitions to use, and returns a string with the HTML produced.
		 *
		 * The following hooks will be run:
		 * 1. `before-tokenize`
		 * 2. `after-tokenize`
		 * 3. `wrap`: On each {@link Token}.
		 *
		 * @param {string} text A string with the code to be highlighted.
		 * @param {Grammar} grammar An object containing the tokens to use.
		 *
		 * Usually a language definition like `Prism.languages.markup`.
		 * @param {string} language The name of the language definition passed to `grammar`.
		 * @returns {string} The highlighted HTML.
		 * @memberof Prism
		 * @public
		 * @example
		 * Prism.highlight('var foo = true;', Prism.languages.javascript, 'javascript');
		 */
		highlight: function (text, grammar, language) {
			var env = {
				code: text,
				grammar: grammar,
				language: language
			};
			_.hooks.run('before-tokenize', env);
			env.tokens = _.tokenize(env.code, env.grammar);
			_.hooks.run('after-tokenize', env);
			return Token.stringify(_.util.encode(env.tokens), env.language);
		},

		/**
		 * This is the heart of Prism, and the most low-level function you can use. It accepts a string of text as input
		 * and the language definitions to use, and returns an array with the tokenized code.
		 *
		 * When the language definition includes nested tokens, the function is called recursively on each of these tokens.
		 *
		 * This method could be useful in other contexts as well, as a very crude parser.
		 *
		 * @param {string} text A string with the code to be highlighted.
		 * @param {Grammar} grammar An object containing the tokens to use.
		 *
		 * Usually a language definition like `Prism.languages.markup`.
		 * @returns {TokenStream} An array of strings and tokens, a token stream.
		 * @memberof Prism
		 * @public
		 * @example
		 * let code = `var foo = 0;`;
		 * let tokens = Prism.tokenize(code, Prism.languages.javascript);
		 * tokens.forEach(token => {
		 *     if (token instanceof Prism.Token && token.type === 'number') {
		 *         console.log(`Found numeric literal: ${token.content}`);
		 *     }
		 * });
		 */
		tokenize: function (text, grammar) {
			var rest = grammar.rest;
			if (rest) {
				for (var token in rest) {
					grammar[token] = rest[token];
				}

				delete grammar.rest;
			}

			var tokenList = new LinkedList();
			addAfter(tokenList, tokenList.head, text);

			matchGrammar(text, tokenList, grammar, tokenList.head, 0);

			return toArray(tokenList);
		},

		/**
		 * @namespace
		 * @memberof Prism
		 * @public
		 */
		hooks: {
			all: {},

			/**
			 * Adds the given callback to the list of callbacks for the given hook.
			 *
			 * The callback will be invoked when the hook it is registered for is run.
			 * Hooks are usually directly run by a highlight function but you can also run hooks yourself.
			 *
			 * One callback function can be registered to multiple hooks and the same hook multiple times.
			 *
			 * @param {string} name The name of the hook.
			 * @param {HookCallback} callback The callback function which is given environment variables.
			 * @public
			 */
			add: function (name, callback) {
				var hooks = _.hooks.all;

				hooks[name] = hooks[name] || [];

				hooks[name].push(callback);
			},

			/**
			 * Runs a hook invoking all registered callbacks with the given environment variables.
			 *
			 * Callbacks will be invoked synchronously and in the order in which they were registered.
			 *
			 * @param {string} name The name of the hook.
			 * @param {Object<string, any>} env The environment variables of the hook passed to all callbacks registered.
			 * @public
			 */
			run: function (name, env) {
				var callbacks = _.hooks.all[name];

				if (!callbacks || !callbacks.length) {
					return;
				}

				for (var i = 0, callback; (callback = callbacks[i++]);) {
					callback(env);
				}
			}
		},

		Token: Token
	};
	_self.Prism = _;


	// Typescript note:
	// The following can be used to import the Token type in JSDoc:
	//
	//   @typedef {InstanceType<import("./prism-core")["Token"]>} Token

	/**
	 * Creates a new token.
	 *
	 * @param {string} type See {@link Token#type type}
	 * @param {string | TokenStream} content See {@link Token#content content}
	 * @param {string|string[]} [alias] The alias(es) of the token.
	 * @param {string} [matchedStr=""] A copy of the full string this token was created from.
	 * @class
	 * @global
	 * @public
	 */
	function Token(type, content, alias, matchedStr) {
		/**
		 * The type of the token.
		 *
		 * This is usually the key of a pattern in a {@link Grammar}.
		 *
		 * @type {string}
		 * @see GrammarToken
		 * @public
		 */
		this.type = type;
		/**
		 * The strings or tokens contained by this token.
		 *
		 * This will be a token stream if the pattern matched also defined an `inside` grammar.
		 *
		 * @type {string | TokenStream}
		 * @public
		 */
		this.content = content;
		/**
		 * The alias(es) of the token.
		 *
		 * @type {string|string[]}
		 * @see GrammarToken
		 * @public
		 */
		this.alias = alias;
		// Copy of the full string this token was created from
		this.length = (matchedStr || '').length | 0;
	}

	/**
	 * A token stream is an array of strings and {@link Token Token} objects.
	 *
	 * Token streams have to fulfill a few properties that are assumed by most functions (mostly internal ones) that process
	 * them.
	 *
	 * 1. No adjacent strings.
	 * 2. No empty strings.
	 *
	 *    The only exception here is the token stream that only contains the empty string and nothing else.
	 *
	 * @typedef {Array<string | Token>} TokenStream
	 * @global
	 * @public
	 */

	/**
	 * Converts the given token or token stream to an HTML representation.
	 *
	 * The following hooks will be run:
	 * 1. `wrap`: On each {@link Token}.
	 *
	 * @param {string | Token | TokenStream} o The token or token stream to be converted.
	 * @param {string} language The name of current language.
	 * @returns {string} The HTML representation of the token or token stream.
	 * @memberof Token
	 * @static
	 */
	Token.stringify = function stringify(o, language) {
		if (typeof o == 'string') {
			return o;
		}
		if (Array.isArray(o)) {
			var s = '';
			o.forEach(function (e) {
				s += stringify(e, language);
			});
			return s;
		}

		var env = {
			type: o.type,
			content: stringify(o.content, language),
			tag: 'span',
			classes: ['token', o.type],
			attributes: {},
			language: language
		};

		var aliases = o.alias;
		if (aliases) {
			if (Array.isArray(aliases)) {
				Array.prototype.push.apply(env.classes, aliases);
			} else {
				env.classes.push(aliases);
			}
		}

		_.hooks.run('wrap', env);

		var attributes = '';
		for (var name in env.attributes) {
			attributes += ' ' + name + '="' + (env.attributes[name] || '').replace(/"/g, '&quot;') + '"';
		}

		return '<' + env.tag + ' class="' + env.classes.join(' ') + '"' + attributes + '>' + env.content + '</' + env.tag + '>';
	};

	/**
	 * @param {RegExp} pattern
	 * @param {number} pos
	 * @param {string} text
	 * @param {boolean} lookbehind
	 * @returns {RegExpExecArray | null}
	 */
	function matchPattern(pattern, pos, text, lookbehind) {
		pattern.lastIndex = pos;
		var match = pattern.exec(text);
		if (match && lookbehind && match[1]) {
			// change the match to remove the text matched by the Prism lookbehind group
			var lookbehindLength = match[1].length;
			match.index += lookbehindLength;
			match[0] = match[0].slice(lookbehindLength);
		}
		return match;
	}

	/**
	 * @param {string} text
	 * @param {LinkedList<string | Token>} tokenList
	 * @param {any} grammar
	 * @param {LinkedListNode<string | Token>} startNode
	 * @param {number} startPos
	 * @param {RematchOptions} [rematch]
	 * @returns {void}
	 * @private
	 *
	 * @typedef RematchOptions
	 * @property {string} cause
	 * @property {number} reach
	 */
	function matchGrammar(text, tokenList, grammar, startNode, startPos, rematch) {
		for (var token in grammar) {
			if (!grammar.hasOwnProperty(token) || !grammar[token]) {
				continue;
			}

			var patterns = grammar[token];
			patterns = Array.isArray(patterns) ? patterns : [patterns];

			for (var j = 0; j < patterns.length; ++j) {
				if (rematch && rematch.cause == token + ',' + j) {
					return;
				}

				var patternObj = patterns[j];
				var inside = patternObj.inside;
				var lookbehind = !!patternObj.lookbehind;
				var greedy = !!patternObj.greedy;
				var alias = patternObj.alias;

				if (greedy && !patternObj.pattern.global) {
					// Without the global flag, lastIndex won't work
					var flags = patternObj.pattern.toString().match(/[imsuy]*$/)[0];
					patternObj.pattern = RegExp(patternObj.pattern.source, flags + 'g');
				}

				/** @type {RegExp} */
				var pattern = patternObj.pattern || patternObj;

				for ( // iterate the token list and keep track of the current token/string position
					var currentNode = startNode.next, pos = startPos;
					currentNode !== tokenList.tail;
					pos += currentNode.value.length, currentNode = currentNode.next
				) {

					if (rematch && pos >= rematch.reach) {
						break;
					}

					var str = currentNode.value;

					if (tokenList.length > text.length) {
						// Something went terribly wrong, ABORT, ABORT!
						return;
					}

					if (str instanceof Token) {
						continue;
					}

					var removeCount = 1; // this is the to parameter of removeBetween
					var match;

					if (greedy) {
						match = matchPattern(pattern, pos, text, lookbehind);
						if (!match) {
							break;
						}

						var from = match.index;
						var to = match.index + match[0].length;
						var p = pos;

						// find the node that contains the match
						p += currentNode.value.length;
						while (from >= p) {
							currentNode = currentNode.next;
							p += currentNode.value.length;
						}
						// adjust pos (and p)
						p -= currentNode.value.length;
						pos = p;

						// the current node is a Token, then the match starts inside another Token, which is invalid
						if (currentNode.value instanceof Token) {
							continue;
						}

						// find the last node which is affected by this match
						for (
							var k = currentNode;
							k !== tokenList.tail && (p < to || typeof k.value === 'string');
							k = k.next
						) {
							removeCount++;
							p += k.value.length;
						}
						removeCount--;

						// replace with the new match
						str = text.slice(pos, p);
						match.index -= pos;
					} else {
						match = matchPattern(pattern, 0, str, lookbehind);
						if (!match) {
							continue;
						}
					}

					// eslint-disable-next-line no-redeclare
					var from = match.index;
					var matchStr = match[0];
					var before = str.slice(0, from);
					var after = str.slice(from + matchStr.length);

					var reach = pos + str.length;
					if (rematch && reach > rematch.reach) {
						rematch.reach = reach;
					}

					var removeFrom = currentNode.prev;

					if (before) {
						removeFrom = addAfter(tokenList, removeFrom, before);
						pos += before.length;
					}

					removeRange(tokenList, removeFrom, removeCount);

					var wrapped = new Token(token, inside ? _.tokenize(matchStr, inside) : matchStr, alias, matchStr);
					currentNode = addAfter(tokenList, removeFrom, wrapped);

					if (after) {
						addAfter(tokenList, currentNode, after);
					}

					if (removeCount > 1) {
						// at least one Token object was removed, so we have to do some rematching
						// this can only happen if the current pattern is greedy

						/** @type {RematchOptions} */
						var nestedRematch = {
							cause: token + ',' + j,
							reach: reach
						};
						matchGrammar(text, tokenList, grammar, currentNode.prev, pos, nestedRematch);

						// the reach might have been extended because of the rematching
						if (rematch && nestedRematch.reach > rematch.reach) {
							rematch.reach = nestedRematch.reach;
						}
					}
				}
			}
		}
	}

	/**
	 * @typedef LinkedListNode
	 * @property {T} value
	 * @property {LinkedListNode<T> | null} prev The previous node.
	 * @property {LinkedListNode<T> | null} next The next node.
	 * @template T
	 * @private
	 */

	/**
	 * @template T
	 * @private
	 */
	function LinkedList() {
		/** @type {LinkedListNode<T>} */
		var head = { value: null, prev: null, next: null };
		/** @type {LinkedListNode<T>} */
		var tail = { value: null, prev: head, next: null };
		head.next = tail;

		/** @type {LinkedListNode<T>} */
		this.head = head;
		/** @type {LinkedListNode<T>} */
		this.tail = tail;
		this.length = 0;
	}

	/**
	 * Adds a new node with the given value to the list.
	 *
	 * @param {LinkedList<T>} list
	 * @param {LinkedListNode<T>} node
	 * @param {T} value
	 * @returns {LinkedListNode<T>} The added node.
	 * @template T
	 */
	function addAfter(list, node, value) {
		// assumes that node != list.tail && values.length >= 0
		var next = node.next;

		var newNode = { value: value, prev: node, next: next };
		node.next = newNode;
		next.prev = newNode;
		list.length++;

		return newNode;
	}
	/**
	 * Removes `count` nodes after the given node. The given node will not be removed.
	 *
	 * @param {LinkedList<T>} list
	 * @param {LinkedListNode<T>} node
	 * @param {number} count
	 * @template T
	 */
	function removeRange(list, node, count) {
		var next = node.next;
		for (var i = 0; i < count && next !== list.tail; i++) {
			next = next.next;
		}
		node.next = next;
		next.prev = node;
		list.length -= i;
	}
	/**
	 * @param {LinkedList<T>} list
	 * @returns {T[]}
	 * @template T
	 */
	function toArray(list) {
		var array = [];
		var node = list.head.next;
		while (node !== list.tail) {
			array.push(node.value);
			node = node.next;
		}
		return array;
	}


	if (!_self.document) {
		if (!_self.addEventListener) {
			// in Node.js
			return _;
		}

		if (!_.disableWorkerMessageHandler) {
			// In worker
			_self.addEventListener('message', function (evt) {
				var message = JSON.parse(evt.data);
				var lang = message.language;
				var code = message.code;
				var immediateClose = message.immediateClose;

				_self.postMessage(_.highlight(code, _.languages[lang], lang));
				if (immediateClose) {
					_self.close();
				}
			}, false);
		}

		return _;
	}

	// Get current script and highlight
	var script = _.util.currentScript();

	if (script) {
		_.filename = script.src;

		if (script.hasAttribute('data-manual')) {
			_.manual = true;
		}
	}

	function highlightAutomaticallyCallback() {
		if (!_.manual) {
			_.highlightAll();
		}
	}

	if (!_.manual) {
		// If the document state is "loading", then we'll use DOMContentLoaded.
		// If the document state is "interactive" and the prism.js script is deferred, then we'll also use the
		// DOMContentLoaded event because there might be some plugins or languages which have also been deferred and they
		// might take longer one animation frame to execute which can create a race condition where only some plugins have
		// been loaded when Prism.highlightAll() is executed, depending on how fast resources are loaded.
		// See https://github.com/PrismJS/prism/issues/2102
		var readyState = document.readyState;
		if (readyState === 'loading' || readyState === 'interactive' && script && script.defer) {
			document.addEventListener('DOMContentLoaded', highlightAutomaticallyCallback);
		} else {
			if (window.requestAnimationFrame) {
				window.requestAnimationFrame(highlightAutomaticallyCallback);
			} else {
				window.setTimeout(highlightAutomaticallyCallback, 16);
			}
		}
	}

	return _;

}(_self));

if (typeof module !== 'undefined' && module.exports) {
	module.exports = Prism;
}

// hack for components to work correctly in node.js
if (typeof global !== 'undefined') {
	global.Prism = Prism;
}

// some additional documentation/types

/**
 * The expansion of a simple `RegExp` literal to support additional properties.
 *
 * @typedef GrammarToken
 * @property {RegExp} pattern The regular expression of the token.
 * @property {boolean} [lookbehind=false] If `true`, then the first capturing group of `pattern` will (effectively)
 * behave as a lookbehind group meaning that the captured text will not be part of the matched text of the new token.
 * @property {boolean} [greedy=false] Whether the token is greedy.
 * @property {string|string[]} [alias] An optional alias or list of aliases.
 * @property {Grammar} [inside] The nested grammar of this token.
 *
 * The `inside` grammar will be used to tokenize the text value of each token of this kind.
 *
 * This can be used to make nested and even recursive language definitions.
 *
 * Note: This can cause infinite recursion. Be careful when you embed different languages or even the same language into
 * each another.
 * @global
 * @public
 */

/**
 * @typedef Grammar
 * @type {Object<string, RegExp | GrammarToken | Array<RegExp | GrammarToken>>}
 * @property {Grammar} [rest] An optional grammar object that will be appended to this grammar.
 * @global
 * @public
 */

/**
 * A function which will invoked after an element was successfully highlighted.
 *
 * @callback HighlightCallback
 * @param {Element} element The element successfully highlighted.
 * @returns {void}
 * @global
 * @public
 */

/**
 * @callback HookCallback
 * @param {Object<string, any>} env The environment variables of the hook.
 * @returns {void}
 * @global
 * @public
 */