mithril.js

var m = (function app(window, undefined) {
	"use strict";
  	var VERSION = "v0.2.2-rc.1";
	function isFunction(object) {
		return typeof object === "function";
	}
	function isObject(object) {
		return type.call(object) === "[object Object]";
	}
	function isString(object) {
		return type.call(object) === "[object String]";
	}
	var isArray = Array.isArray || function (object) {
		return type.call(object) === "[object Array]";
	};
	var type = {}.toString;
	var parser = /(?:(^|#|\.)([^#\.\[\]]+))|(\[.+?\])/g, attrParser = /\[(.+?)(?:=("|'|)(.*?)\2)?\]/;
	var voidElements = /^(AREA|BASE|BR|COL|COMMAND|EMBED|HR|IMG|INPUT|KEYGEN|LINK|META|PARAM|SOURCE|TRACK|WBR)$/;
	var noop = function () {};

	// caching commonly used variables
	var $document, $location, $requestAnimationFrame, $cancelAnimationFrame;

	// self invoking function needed because of the way mocks work
	function initialize(window) {
		$document = window.document;
		$location = window.location;
		$cancelAnimationFrame = window.cancelAnimationFrame || window.clearTimeout;
		$requestAnimationFrame = window.requestAnimationFrame || window.setTimeout;
	}

	initialize(window);

	m.version = function() {
		return VERSION;
	};

	/**
	 * @typedef {String} Tag
	 * A string that looks like -> div.classname#id[param=one][param2=two]
	 * Which describes a DOM node
	 */

	/**
	 *
	 * @param {Tag} The DOM node tag
	 * @param {Object=[]} optional key-value pairs to be mapped to DOM attrs
	 * @param {...mNode=[]} Zero or more Mithril child nodes. Can be an array, or splat (optional)
	 *
	 */
	function m(tag, pairs) {
		for (var args = [], i = 1; i < arguments.length; i++) {
			args[i - 1] = arguments[i];
		}
		if (isObject(tag)) return parameterize(tag, args);
		var hasAttrs = pairs != null && isObject(pairs) && !("tag" in pairs || "view" in pairs || "subtree" in pairs);
		var attrs = hasAttrs ? pairs : {};
		var classAttrName = "class" in attrs ? "class" : "className";
		var cell = {tag: "div", attrs: {}};
		var match, classes = [];
		if (!isString(tag)) throw new Error("selector in m(selector, attrs, children) should be a string");
		while ((match = parser.exec(tag)) != null) {
			if (match[1] === "" && match[2]) cell.tag = match[2];
			else if (match[1] === "#") cell.attrs.id = match[2];
			else if (match[1] === ".") classes.push(match[2]);
			else if (match[3][0] === "[") {
				var pair = attrParser.exec(match[3]);
				cell.attrs[pair[1]] = pair[3] || (pair[2] ? "" :true);
			}
		}

		var children = hasAttrs ? args.slice(1) : args;
		if (children.length === 1 && isArray(children[0])) {
			cell.children = children[0];
		}
		else {
			cell.children = children;
		}

		for (var attrName in attrs) {
			if (attrs.hasOwnProperty(attrName)) {
				if (attrName === classAttrName && attrs[attrName] != null && attrs[attrName] !== "") {
					classes.push(attrs[attrName]);
					cell.attrs[attrName] = ""; //create key in correct iteration order
				}
				else cell.attrs[attrName] = attrs[attrName];
			}
		}
		if (classes.length) cell.attrs[classAttrName] = classes.join(" ");

		return cell;
	}
	function forEach(list, f) {
		for (var i = 0; i < list.length && !f(list[i], i++);) {}
	}
	function forKeys(list, f) {
		forEach(list, function (attrs, i) {
			return (attrs = attrs && attrs.attrs) && attrs.key != null && f(attrs, i);
		});
	}
	// This function was causing deopts in Chrome.
	function dataToString(data) {
		//data.toString() might throw or return null if data is the return value of Console.log in Firefox (behavior depends on version)
		try {
			if (data == null || data.toString() == null) return "";
		} catch (e) {
			return "";
		}
		return data;
	}
	// This function was causing deopts in Chrome.
	function injectTextNode(parentElement, first, index, data) {
		try {
			insertNode(parentElement, first, index);
			first.nodeValue = data;
		} catch (e) {} //IE erroneously throws error when appending an empty text node after a null
	}

	function flatten(list) {
		//recursively flatten array
		for (var i = 0; i < list.length; i++) {
			if (isArray(list[i])) {
				list = list.concat.apply([], list);
				//check current index again and flatten until there are no more nested arrays at that index
				i--;
			}
		}
		return list;
	}

	function insertNode(parentElement, node, index) {
		parentElement.insertBefore(node, parentElement.childNodes[index] || null);
	}

	var DELETION = 1, INSERTION = 2, MOVE = 3;

	function handleKeysDiffer(data, existing, cached, parentElement) {
		forKeys(data, function (key, i) {
			existing[key = key.key] = existing[key] ? {
				action: MOVE,
				index: i,
				from: existing[key].index,
				element: cached.nodes[existing[key].index] || $document.createElement("div")
			} : {action: INSERTION, index: i};
		});
		var actions = [];
		for (var prop in existing) actions.push(existing[prop]);
		var changes = actions.sort(sortChanges), newCached = new Array(cached.length);
		newCached.nodes = cached.nodes.slice();

		forEach(changes, function (change) {
			var index = change.index;
			if (change.action === DELETION) {
				clear(cached[index].nodes, cached[index]);
				newCached.splice(index, 1);
			}
			if (change.action === INSERTION) {
				var dummy = $document.createElement("div");
				dummy.key = data[index].attrs.key;
				insertNode(parentElement, dummy, index);
				newCached.splice(index, 0, {
					attrs: {key: data[index].attrs.key},
					nodes: [dummy]
				});
				newCached.nodes[index] = dummy;
			}

			if (change.action === MOVE) {
				var changeElement = change.element;
				var maybeChanged = parentElement.childNodes[index];
				if (maybeChanged !== changeElement && changeElement !== null) {
					parentElement.insertBefore(changeElement, maybeChanged || null);
				}
				newCached[index] = cached[change.from];
				newCached.nodes[index] = changeElement;
			}
		});

		return newCached;
	}

	function diffKeys(data, cached, existing, parentElement) {
		var keysDiffer = data.length !== cached.length;
		if (!keysDiffer) {
			forKeys(data, function (attrs, i) {
				var cachedCell = cached[i];
				return keysDiffer = cachedCell && cachedCell.attrs && cachedCell.attrs.key !== attrs.key;
			});
		}

		return keysDiffer ? handleKeysDiffer(data, existing, cached, parentElement) : cached;
	}

	function diffArray(data, cached, nodes) {
		//diff the array itself

		//update the list of DOM nodes by collecting the nodes from each item
		forEach(data, function (_, i) {
			if (cached[i] != null) nodes.push.apply(nodes, cached[i].nodes);
		})
		//remove items from the end of the array if the new array is shorter than the old one. if errors ever happen here, the issue is most likely
		//a bug in the construction of the `cached` data structure somewhere earlier in the program
		forEach(cached.nodes, function (node, i) {
			if (node.parentNode != null && nodes.indexOf(node) < 0) clear([node], [cached[i]]);
		})
		if (data.length < cached.length) cached.length = data.length;
		cached.nodes = nodes;
	}

	function buildArrayKeys(data) {
		var guid = 0;
		forKeys(data, function () {
			forEach(data, function (attrs) {
				if ((attrs = attrs && attrs.attrs) && attrs.key == null) attrs.key = "__mithril__" + guid++;
			})
			return 1;
		});
	}

	function maybeRecreateObject(data, cached, dataAttrKeys) {
		//if an element is different enough from the one in cache, recreate it
		if (data.tag !== cached.tag ||
				dataAttrKeys.sort().join() !== Object.keys(cached.attrs).sort().join() ||
				data.attrs.id !== cached.attrs.id ||
				data.attrs.key !== cached.attrs.key ||
				(m.redraw.strategy() === "all" && (!cached.configContext || cached.configContext.retain !== true)) ||
				(m.redraw.strategy() === "diff" && cached.configContext && cached.configContext.retain === false)) {
			if (cached.nodes.length) clear(cached.nodes);
			if (cached.configContext && isFunction(cached.configContext.onunload)) cached.configContext.onunload();
			if (cached.controllers) {
				forEach(cached.controllers, function (controller) {
					if (controller.unload) controller.onunload({preventDefault: noop});
				});
			}
		}
	}

	function getObjectNamespace(data, namespace) {
		return data.attrs.xmlns ? data.attrs.xmlns :
			data.tag === "svg" ? "http://www.w3.org/2000/svg" :
			data.tag === "math" ? "http://www.w3.org/1998/Math/MathML" :
			namespace;
	}

	function unloadCachedControllers(cached, views, controllers) {
		if (controllers.length) {
			cached.views = views;
			cached.controllers = controllers;
			forEach(controllers, function (controller) {
				if (controller.onunload && controller.onunload.$old) controller.onunload = controller.onunload.$old;
				if (pendingRequests && controller.onunload) {
					var onunload = controller.onunload;
					controller.onunload = noop;
					controller.onunload.$old = onunload;
				}
			});
		}
	}

	function scheduleConfigsToBeCalled(configs, data, node, isNew, cached) {
		//schedule configs to be called. They are called after `build`
		//finishes running
		if (isFunction(data.attrs.config)) {
			var context = cached.configContext = cached.configContext || {};

			//bind
			configs.push(function() {
				return data.attrs.config.call(data, node, !isNew, context, cached);
			});
		}
	}

	function buildUpdatedNode(cached, data, editable, hasKeys, namespace, views, configs, controllers) {
		var node = cached.nodes[0];
		if (hasKeys) setAttributes(node, data.tag, data.attrs, cached.attrs, namespace);
		cached.children = build(node, data.tag, undefined, undefined, data.children, cached.children, false, 0, data.attrs.contenteditable ? node : editable, namespace, configs);
		cached.nodes.intact = true;

		if (controllers.length) {
			cached.views = views;
			cached.controllers = controllers;
		}

		return node;
	}

	function handleNonexistentNodes(data, parentElement, index) {
		var nodes;
		if (data.$trusted) {
			nodes = injectHTML(parentElement, index, data);
		}
		else {
			nodes = [$document.createTextNode(data)];
			if (!parentElement.nodeName.match(voidElements)) insertNode(parentElement, nodes[0], index);
		}

		var cached = typeof data === "string" || typeof data === "number" || typeof data === "boolean" ? new data.constructor(data) : data;
		cached.nodes = nodes;
		return cached;
	}

	function reattachNodes(data, cached, parentElement, editable, index, parentTag) {
		var nodes = cached.nodes;
		if (!editable || editable !== $document.activeElement) {
			if (data.$trusted) {
				clear(nodes, cached)
				nodes = injectHTML(parentElement, index, data)
			} else if (parentTag === "textarea") {
				// <textarea> uses `value` instead of `nodeValue`.
				parentElement.value = data
			} else if (editable) {
				// contenteditable nodes use `innerHTML` instead of `nodeValue`.
				editable.innerHTML = data
			} else {
				// was a trusted string
				if (nodes[0].nodeType === 1 || nodes.length > 1 || (nodes[0].nodeValue.trim && !nodes[0].nodeValue.trim())) {
					clear(cached.nodes, cached)
					nodes = [$document.createTextNode(data)]
				}
				injectTextNode(parentElement, nodes[0], index, data);
			}
		}
		cached = new data.constructor(data);
		cached.nodes = nodes;
		return cached;
	}

	function handleText(cached, data, index, parentElement, shouldReattach, editable, parentTag) {
		//handle text nodes
		return cached.nodes.length === 0 ? handleNonexistentNodes(data, parentElement, index) :
			cached.valueOf() !== data.valueOf() || shouldReattach === true ?
				reattachNodes(data, cached, parentElement, editable, index, parentTag) :
			(cached.nodes.intact = true, cached);
	}

	function getSubArrayCount(item) {
		if (item.$trusted) {
			//fix offset of next element if item was a trusted string w/ more than one html element
			//the first clause in the regexp matches elements
			//the second clause (after the pipe) matches text nodes
			var match = item.match(/<[^\/]|\>\s*[^<]/g);
			if (match != null) return match.length;
		}
		else if (isArray(item)) {
			return item.length;
		}
		return 1;
	}

	function buildArray(data, cached, parentElement, index, parentTag, shouldReattach, editable, namespace, configs) {
		data = flatten(data);
		var nodes = [], intact = cached.length === data.length, subArrayCount = 0;

		//keys algorithm: sort elements without recreating them if keys are present
		//1) create a map of all existing keys, and mark all for deletion
		//2) add new keys to map and mark them for addition
		//3) if key exists in new list, change action from deletion to a move
		//4) for each key, handle its corresponding action as marked in previous steps
		var existing = {}, shouldMaintainIdentities = false;
		forKeys(cached, function (attrs, i) {
			shouldMaintainIdentities = true;
			existing[cached[i].attrs.key] = {action: DELETION, index: i};
		});

		buildArrayKeys(data);
		if (shouldMaintainIdentities) cached = diffKeys(data, cached, existing, parentElement);
		//end key algorithm

		var cacheCount = 0;
		//faster explicitly written
		for (var i = 0, len = data.length; i < len; i++) {
			//diff each item in the array
			var item = build(parentElement, parentTag, cached, index, data[i], cached[cacheCount], shouldReattach, index + subArrayCount || subArrayCount, editable, namespace, configs);

			if (item !== undefined) {
				intact = intact && item.nodes.intact;
				subArrayCount += getSubArrayCount(item);
				cached[cacheCount++] = item;
			}
		}

		if (!intact) diffArray(data, cached, nodes);
		return cached
	}

	function makeCache(data, cached, index, parentIndex, parentCache) {
		if (cached != null) {
			if (type.call(cached) === type.call(data)) return cached;

			if (parentCache && parentCache.nodes) {
				var offset = index - parentIndex, end = offset + (isArray(data) ? data : cached.nodes).length;
				clear(parentCache.nodes.slice(offset, end), parentCache.slice(offset, end));
			} else if (cached.nodes) {
				clear(cached.nodes, cached);
			}
		}

		cached = new data.constructor();
		//if constructor creates a virtual dom element, use a blank object
		//as the base cached node instead of copying the virtual el (#277)
		if (cached.tag) cached = {};
		cached.nodes = [];
		return cached;
	}

	function constructNode(data, namespace) {
		return namespace === undefined ?
			data.attrs.is ? $document.createElement(data.tag, data.attrs.is) : $document.createElement(data.tag) :
			data.attrs.is ? $document.createElementNS(namespace, data.tag, data.attrs.is) : $document.createElementNS(namespace, data.tag);
	}

	function constructAttrs(data, node, namespace, hasKeys) {
		return hasKeys ? setAttributes(node, data.tag, data.attrs, {}, namespace) : data.attrs;
	}

	function constructChildren(data, node, cached, editable, namespace, configs) {
		return data.children != null && data.children.length > 0 ?
			build(node, data.tag, undefined, undefined, data.children, cached.children, true, 0, data.attrs.contenteditable ? node : editable, namespace, configs) :
			data.children;
	}

	function reconstructCached(data, attrs, children, node, namespace, views, controllers) {
		var cached = {tag: data.tag, attrs: attrs, children: children, nodes: [node]};
		unloadCachedControllers(cached, views, controllers);
		if (cached.children && !cached.children.nodes) cached.children.nodes = [];
		//edge case: setting value on <select> doesn't work before children exist, so set it again after children have been created
		if (data.tag === "select" && "value" in data.attrs) setAttributes(node, data.tag, {value: data.attrs.value}, {}, namespace);
		return cached
	}

	function getController(views, view, cachedControllers, controller) {
		var controllerIndex = m.redraw.strategy() === "diff" && views ? views.indexOf(view) : -1;
		return controllerIndex > -1 ? cachedControllers[controllerIndex] :
			typeof controller === "function" ? new controller() : {};
	}

	function updateLists(views, controllers, view, controller) {
		if (controller.onunload != null) unloaders.push({controller: controller, handler: controller.onunload});
		views.push(view);
		controllers.push(controller);
	}

	function checkView(data, view, cached, cachedControllers, controllers, views) {
		var controller = getController(cached.views, view, cachedControllers, data.controller);
		//Faster to coerce to number and check for NaN
		var key = +(data && data.attrs && data.attrs.key);
		data = pendingRequests === 0 || forcing || cachedControllers && cachedControllers.indexOf(controller) > -1 ? data.view(controller) : {tag: "placeholder"};
		if (data.subtree === "retain") return cached;
		if (key === key) (data.attrs = data.attrs || {}).key = key;
		updateLists(views, controllers, view, controller);
		return data;
	}

	function markViews(data, cached, views, controllers) {
		var cachedControllers = cached && cached.controllers;
		while (data.view != null) data = checkView(data, data.view.$original || data.view, cached, cachedControllers, controllers, views);
		return data;
	}

	function buildObject(data, cached, editable, parentElement, index, shouldReattach, namespace, configs) {
		var views = [], controllers = [];
		data = markViews(data, cached, views, controllers);
		if (!data.tag && controllers.length) throw new Error("Component template must return a virtual element, not an array, string, etc.");
		data.attrs = data.attrs || {};
		cached.attrs = cached.attrs || {};
		var dataAttrKeys = Object.keys(data.attrs);
		var hasKeys = dataAttrKeys.length > ("key" in data.attrs ? 1 : 0);
		maybeRecreateObject(data, cached, dataAttrKeys);
		if (!isString(data.tag)) return;
		var isNew = cached.nodes.length === 0;
		namespace = getObjectNamespace(data, namespace);
		var node;
		if (isNew) {
			node = constructNode(data, namespace);
			//set attributes first, then create children
			var attrs = constructAttrs(data, node, namespace, hasKeys)
			var children = constructChildren(data, node, cached, editable, namespace, configs);
			cached = reconstructCached(data, attrs, children, node, namespace, views, controllers);
		}
		else {
			node = buildUpdatedNode(cached, data, editable, hasKeys, namespace, views, configs, controllers);
		}
		if (isNew || shouldReattach === true && node != null) insertNode(parentElement, node, index);
		//schedule configs to be called. They are called after `build`
		//finishes running
		scheduleConfigsToBeCalled(configs, data, node, isNew, cached);
		return cached
	}

	function build(parentElement, parentTag, parentCache, parentIndex, data, cached, shouldReattach, index, editable, namespace, configs) {
		//`build` is a recursive function that manages creation/diffing/removal
		//of DOM elements based on comparison between `data` and `cached`
		//the diff algorithm can be summarized as this:
		//1 - compare `data` and `cached`
		//2 - if they are different, copy `data` to `cached` and update the DOM
		//    based on what the difference is
		//3 - recursively apply this algorithm for every array and for the
		//    children of every virtual element

		//the `cached` data structure is essentially the same as the previous
		//redraw's `data` data structure, with a few additions:
		//- `cached` always has a property called `nodes`, which is a list of
		//   DOM elements that correspond to the data represented by the
		//   respective virtual element
		//- in order to support attaching `nodes` as a property of `cached`,
		//   `cached` is *always* a non-primitive object, i.e. if the data was
		//   a string, then cached is a String instance. If data was `null` or
		//   `undefined`, cached is `new String("")`
		//- `cached also has a `configContext` property, which is the state
		//   storage object exposed by config(element, isInitialized, context)
		//- when `cached` is an Object, it represents a virtual element; when
		//   it's an Array, it represents a list of elements; when it's a
		//   String, Number or Boolean, it represents a text node

		//`parentElement` is a DOM element used for W3C DOM API calls
		//`parentTag` is only used for handling a corner case for textarea
		//values
		//`parentCache` is used to remove nodes in some multi-node cases
		//`parentIndex` and `index` are used to figure out the offset of nodes.
		//They're artifacts from before arrays started being flattened and are
		//likely refactorable
		//`data` and `cached` are, respectively, the new and old nodes being
		//diffed
		//`shouldReattach` is a flag indicating whether a parent node was
		//recreated (if so, and if this node is reused, then this node must
		//reattach itself to the new parent)
		//`editable` is a flag that indicates whether an ancestor is
		//contenteditable
		//`namespace` indicates the closest HTML namespace as it cascades down
		//from an ancestor
		//`configs` is a list of config functions to run after the topmost
		//`build` call finishes running

		//there's logic that relies on the assumption that null and undefined
		//data are equivalent to empty strings
		//- this prevents lifecycle surprises from procedural helpers that mix
		//  implicit and explicit return statements (e.g.
		//  function foo() {if (cond) return m("div")}
		//- it simplifies diffing code
		data = dataToString(data);
		if (data.subtree === "retain") return cached;
		cached = makeCache(data, cached, index, parentIndex, parentCache);
		return isArray(data) ? buildArray(data, cached, parentElement, index, parentTag, shouldReattach, editable, namespace, configs) :
			data != null && isObject(data) ? buildObject(data, cached, editable, parentElement, index, shouldReattach, namespace, configs) :
			!isFunction(data) ? handleText(cached, data, index, parentElement, shouldReattach, editable, parentTag) :
			cached;
	}
	function sortChanges(a, b) { return a.action - b.action || a.index - b.index; }
	function setAttributes(node, tag, dataAttrs, cachedAttrs, namespace) {
		for (var attrName in dataAttrs) {
			var dataAttr = dataAttrs[attrName];
			var cachedAttr = cachedAttrs[attrName];
			if (!(attrName in cachedAttrs) || (cachedAttr !== dataAttr)) {
				cachedAttrs[attrName] = dataAttr;
				try {
					//`config` isn't a real attributes, so ignore it
					if (attrName === "config" || attrName === "key") continue;
					//hook event handlers to the auto-redrawing system
					else if (isFunction(dataAttr) && attrName.slice(0, 2) === "on") {
						node[attrName] = autoredraw(dataAttr, node);
					}
					//handle `style: {...}`
					else if (attrName === "style" && dataAttr != null && isObject(dataAttr)) {
						for (var rule in dataAttr) {
							if (cachedAttr == null || cachedAttr[rule] !== dataAttr[rule]) node.style[rule] = dataAttr[rule];
						}
						for (var rule in cachedAttr) {
							if (!(rule in dataAttr)) node.style[rule] = "";
						}
					}
					//handle SVG
					else if (namespace != null) {
						if (attrName === "href") node.setAttributeNS("http://www.w3.org/1999/xlink", "href", dataAttr);
						else node.setAttribute(attrName === "className" ? "class" : attrName, dataAttr);
					}
					//handle cases that are properties (but ignore cases where we should use setAttribute instead)
					//- list and form are typically used as strings, but are DOM element references in js
					//- when using CSS selectors (e.g. `m("[style='']")`), style is used as a string, but it's an object in js
					else if (attrName in node && attrName !== "list" && attrName !== "style" && attrName !== "form" && attrName !== "type" && attrName !== "width" && attrName !== "height") {
						//#348 don't set the value if not needed otherwise cursor placement breaks in Chrome
						if (tag !== "input" || node[attrName] !== dataAttr) node[attrName] = dataAttr;
					}
					else node.setAttribute(attrName, dataAttr);
				}
				catch (e) {
					//swallow IE's invalid argument errors to mimic HTML's fallback-to-doing-nothing-on-invalid-attributes behavior
					if (e.message.indexOf("Invalid argument") < 0) throw e;
				}
			}
			//#348 dataAttr may not be a string, so use loose comparison (double equal) instead of strict (triple equal)
			else if (attrName === "value" && tag === "input" && node.value != dataAttr) {
				node.value = dataAttr;
			}
		}
		return cachedAttrs;
	}
	function clear(nodes, cached) {
		for (var i = nodes.length - 1; i > -1; i--) {
			if (nodes[i] && nodes[i].parentNode) {
				try { nodes[i].parentNode.removeChild(nodes[i]); }
				catch (e) {} //ignore if this fails due to order of events (see http://stackoverflow.com/questions/21926083/failed-to-execute-removechild-on-node)
				cached = [].concat(cached);
				if (cached[i]) unload(cached[i]);
			}
		}
		//release memory if nodes is an array. This check should fail if nodes is a NodeList (see loop above)
		if (nodes.length) nodes.length = 0;
	}
	function unload(cached) {
		if (cached.configContext && isFunction(cached.configContext.onunload)) {
			cached.configContext.onunload();
			cached.configContext.onunload = null;
		}
		if (cached.controllers) {
			forEach(cached.controllers, function (controller) {
				if (isFunction(controller.onunload)) controller.onunload({preventDefault: noop});
			});
		}
		if (cached.children) {
			if (isArray(cached.children)) forEach(cached.children, unload);
			else if (cached.children.tag) unload(cached.children);
		}
	}
	function injectHTML(parentElement, index, data) {
		var nextSibling = parentElement.childNodes[index];
		if (nextSibling) {
			var isElement = nextSibling.nodeType !== 1;
			var placeholder = $document.createElement("span");
			if (isElement) {
				parentElement.insertBefore(placeholder, nextSibling || null);
				placeholder.insertAdjacentHTML("beforebegin", data);
				parentElement.removeChild(placeholder);
			}
			else nextSibling.insertAdjacentHTML("beforebegin", data);
		}
		else {
			if (window.Range && window.Range.prototype.createContextualFragment) {
				parentElement.appendChild($document.createRange().createContextualFragment(data));
			}
			else parentElement.insertAdjacentHTML("beforeend", data);
		}
		var nodes = [];
		while (parentElement.childNodes[index] !== nextSibling) {
			nodes.push(parentElement.childNodes[index]);
			index++;
		}
		return nodes;
	}
	function autoredraw(callback, object) {
		return function(e) {
			e = e || event;
			m.redraw.strategy("diff");
			m.startComputation();
			try { return callback.call(object, e); }
			finally {
				endFirstComputation();
			}
		};
	}

	var html;
	var documentNode = {
		appendChild: function(node) {
			if (html === undefined) html = $document.createElement("html");
			if ($document.documentElement && $document.documentElement !== node) {
				$document.replaceChild(node, $document.documentElement);
			}
			else $document.appendChild(node);
			this.childNodes = $document.childNodes;
		},
		insertBefore: function(node) {
			this.appendChild(node);
		},
		childNodes: []
	};
	var nodeCache = [], cellCache = {};
	m.render = function(root, cell, forceRecreation) {
		var configs = [];
		if (!root) throw new Error("Ensure the DOM element being passed to m.route/m.mount/m.render is not undefined.");
		var id = getCellCacheKey(root);
		var isDocumentRoot = root === $document;
		var node = isDocumentRoot || root === $document.documentElement ? documentNode : root;
		if (isDocumentRoot && cell.tag !== "html") cell = {tag: "html", attrs: {}, children: cell};
		if (cellCache[id] === undefined) clear(node.childNodes);
		if (forceRecreation === true) reset(root);
		cellCache[id] = build(node, null, undefined, undefined, cell, cellCache[id], false, 0, null, undefined, configs);
		forEach(configs, function (config) { config(); });
	};
	function getCellCacheKey(element) {
		var index = nodeCache.indexOf(element);
		return index < 0 ? nodeCache.push(element) - 1 : index;
	}

	m.trust = function(value) {
		value = new String(value);
		value.$trusted = true;
		return value;
	};

	function gettersetter(store) {
		var prop = function() {
			if (arguments.length) store = arguments[0];
			return store;
		};

		prop.toJSON = function() {
			return store;
		};

		return prop;
	}

	m.prop = function (store) {
		//note: using non-strict equality check here because we're checking if store is null OR undefined
		if ((store != null && isObject(store) || isFunction(store)) && isFunction(store.then)) {
			return propify(store);
		}

		return gettersetter(store);
	};

	var roots = [], components = [], controllers = [], lastRedrawId = null, lastRedrawCallTime = 0, computePreRedrawHook = null, computePostRedrawHook = null, topComponent, unloaders = [];
	var FRAME_BUDGET = 16; //60 frames per second = 1 call per 16 ms
	function parameterize(component, args) {
		var controller = function() {
			return (component.controller || noop).apply(this, args) || this;
		};
		if (component.controller) controller.prototype = component.controller.prototype;
		var view = function(ctrl) {
			var currentArgs = arguments.length > 1 ? args.concat([].slice.call(arguments, 1)) : args;
			return component.view.apply(component, currentArgs ? [ctrl].concat(currentArgs) : [ctrl]);
		};
		view.$original = component.view;
		var output = {controller: controller, view: view};
		if (args[0] && args[0].key != null) output.attrs = {key: args[0].key};
		return output;
	}
	m.component = function(component) {
		for (var args = [], i = 1; i < arguments.length; i++) args.push(arguments[i]);
		return parameterize(component, args);
	};
	m.mount = m.module = function(root, component) {
		if (!root) throw new Error("Please ensure the DOM element exists before rendering a template into it.");
		var index = roots.indexOf(root);
		if (index < 0) index = roots.length;

		var isPrevented = false;
		var event = {preventDefault: function() {
			isPrevented = true;
			computePreRedrawHook = computePostRedrawHook = null;
		}};

		forEach(unloaders, function (unloader) {
			unloader.handler.call(unloader.controller, event);
			unloader.controller.onunload = null;
		});

		if (isPrevented) {
			forEach(unloaders, function (unloader) {
				unloader.controller.onunload = unloader.handler;
			});
		}
		else unloaders = [];

		if (controllers[index] && isFunction(controllers[index].onunload)) {
			controllers[index].onunload(event);
		}

		var isNullComponent = component === null;

		if (!isPrevented) {
			m.redraw.strategy("all");
			m.startComputation();
			roots[index] = root;
			var currentComponent = component ? (topComponent = component) : (topComponent = component = {controller: noop});
			var controller = new (component.controller || noop)();
			//controllers may call m.mount recursively (via m.route redirects, for example)
			//this conditional ensures only the last recursive m.mount call is applied
			if (currentComponent === topComponent) {
				controllers[index] = controller;
				components[index] = component;
			}
			endFirstComputation();
			if (isNullComponent) {
				removeRootElement(root, index);
			}
			return controllers[index];
		}
		if (isNullComponent) {
			removeRootElement(root, index);
		}
	};

	function removeRootElement(root, index) {
		roots.splice(index, 1);
		controllers.splice(index, 1);
		components.splice(index, 1);
		reset(root);
		nodeCache.splice(getCellCacheKey(root), 1);
	}

	var redrawing = false, forcing = false;
	m.redraw = function(force) {
		if (redrawing) return;
		redrawing = true;
		if (force) forcing = true;
		try {
			//lastRedrawId is a positive number if a second redraw is requested before the next animation frame
			//lastRedrawID is null if it's the first redraw and not an event handler
			if (lastRedrawId && !force) {
				//when setTimeout: only reschedule redraw if time between now and previous redraw is bigger than a frame, otherwise keep currently scheduled timeout
				//when rAF: always reschedule redraw
				if ($requestAnimationFrame === window.requestAnimationFrame || new Date - lastRedrawCallTime > FRAME_BUDGET) {
					if (lastRedrawId > 0) $cancelAnimationFrame(lastRedrawId);
					lastRedrawId = $requestAnimationFrame(redraw, FRAME_BUDGET);
				}
			}
			else {
				redraw();
				lastRedrawId = $requestAnimationFrame(function() { lastRedrawId = null; }, FRAME_BUDGET);
			}
		}
		finally {
			redrawing = forcing = false;
		}
	};
	m.redraw.strategy = m.prop();
	function redraw() {
		if (computePreRedrawHook) {
			computePreRedrawHook();
			computePreRedrawHook = null;
		}
		forEach(roots, function (root, i) {
			var component = components[i];
			if (controllers[i]) {
				var args = [controllers[i]];
				m.render(root, component.view ? component.view(controllers[i], args) : "");
			}
		});
		//after rendering within a routed context, we need to scroll back to the top, and fetch the document title for history.pushState
		if (computePostRedrawHook) {
			computePostRedrawHook();
			computePostRedrawHook = null;
		}
		lastRedrawId = null;
		lastRedrawCallTime = new Date;
		m.redraw.strategy("diff");
	}

	var pendingRequests = 0;
	m.startComputation = function() { pendingRequests++; };
	m.endComputation = function() {
		if (pendingRequests > 1) pendingRequests--;
		else {
			pendingRequests = 0;
			m.redraw();
		}
	}

	function endFirstComputation() {
		if (m.redraw.strategy() === "none") {
			pendingRequests--;
			m.redraw.strategy("diff");
		}
		else m.endComputation();
	}

	m.withAttr = function(prop, withAttrCallback, callbackThis) {
		return function(e) {
			e = e || event;
			var currentTarget = e.currentTarget || this;
			var _this = callbackThis || this;
			withAttrCallback.call(_this, prop in currentTarget ? currentTarget[prop] : currentTarget.getAttribute(prop));
		};
	};

	//routing
	var modes = {pathname: "", hash: "#", search: "?"};
	var redirect = noop, routeParams, currentRoute, isDefaultRoute = false;
	m.route = function(root, arg1, arg2, vdom) {
		//m.route()
		if (arguments.length === 0) return currentRoute;
		//m.route(el, defaultRoute, routes)
		else if (arguments.length === 3 && isString(arg1)) {
			redirect = function(source) {
				var path = currentRoute = normalizeRoute(source);
				if (!routeByValue(root, arg2, path)) {
					if (isDefaultRoute) throw new Error("Ensure the default route matches one of the routes defined in m.route");
					isDefaultRoute = true;
					m.route(arg1, true);
					isDefaultRoute = false;
				}
			};
			var listener = m.route.mode === "hash" ? "onhashchange" : "onpopstate";
			window[listener] = function() {
				var path = $location[m.route.mode];
				if (m.route.mode === "pathname") path += $location.search;
				if (currentRoute !== normalizeRoute(path)) redirect(path);
			};

			computePreRedrawHook = setScroll;
			window[listener]();
		}
		//config: m.route
		else if (root.addEventListener || root.attachEvent) {
			root.href = (m.route.mode !== 'pathname' ? $location.pathname : '') + modes[m.route.mode] + vdom.attrs.href;
			if (root.addEventListener) {
				root.removeEventListener("click", routeUnobtrusive);
				root.addEventListener("click", routeUnobtrusive);
			}
			else {
				root.detachEvent("onclick", routeUnobtrusive);
				root.attachEvent("onclick", routeUnobtrusive);
			}
		}
		//m.route(route, params, shouldReplaceHistoryEntry)
		else if (isString(root)) {
			var oldRoute = currentRoute;
			currentRoute = root;
			var args = arg1 || {};
			var queryIndex = currentRoute.indexOf("?");
			var params = queryIndex > -1 ? parseQueryString(currentRoute.slice(queryIndex + 1)) : {};
			for (var i in args) params[i] = args[i];
			var querystring = buildQueryString(params);
			var currentPath = queryIndex > -1 ? currentRoute.slice(0, queryIndex) : currentRoute;
			if (querystring) currentRoute = currentPath + (currentPath.indexOf("?") === -1 ? "?" : "&") + querystring;

			var shouldReplaceHistoryEntry = (arguments.length === 3 ? arg2 : arg1) === true || oldRoute === root;

			if (window.history.pushState) {
				computePreRedrawHook = setScroll;
				computePostRedrawHook = function() {
					window.history[shouldReplaceHistoryEntry ? "replaceState" : "pushState"](null, $document.title, modes[m.route.mode] + currentRoute);
				};
				redirect(modes[m.route.mode] + currentRoute);
			}
			else {
				$location[m.route.mode] = currentRoute;
				redirect(modes[m.route.mode] + currentRoute);
			}
		}
	};
	m.route.param = function(key) {
		if (!routeParams) throw new Error("You must call m.route(element, defaultRoute, routes) before calling m.route.param()");
		if( !key ){
			return routeParams;
		}
		return routeParams[key];
	};
	m.route.mode = "search";
	function normalizeRoute(route) {
		return route.slice(modes[m.route.mode].length);
	}
	function routeByValue(root, router, path) {
		routeParams = {};

		var queryStart = path.indexOf("?");
		if (queryStart !== -1) {
			routeParams = parseQueryString(path.substr(queryStart + 1, path.length));
			path = path.substr(0, queryStart);
		}

		// Get all routes and check if there's
		// an exact match for the current path
		var keys = Object.keys(router);
		var index = keys.indexOf(path);
		if(index !== -1){
			m.mount(root, router[keys [index]]);
			return true;
		}

		for (var route in router) {
			if (route === path) {
				m.mount(root, router[route]);
				return true;
			}

			var matcher = new RegExp("^" + route.replace(/:[^\/]+?\.{3}/g, "(.*?)").replace(/:[^\/]+/g, "([^\\/]+)") + "\/?$");

			if (matcher.test(path)) {
				path.replace(matcher, function() {
					var keys = route.match(/:[^\/]+/g) || [];
					var values = [].slice.call(arguments, 1, -2);
					forEach(keys, function (key, i) {
						routeParams[key.replace(/:|\./g, "")] = decodeURIComponent(values[i]);
					})
					m.mount(root, router[route]);
				});
				return true;
			}
		}
	}
	function routeUnobtrusive(e) {
		e = e || event;

		if (e.ctrlKey || e.metaKey || e.which === 2) return;

		if (e.preventDefault) e.preventDefault();
		else e.returnValue = false;

		var currentTarget = e.currentTarget || e.srcElement;
		var args = m.route.mode === "pathname" && currentTarget.search ? parseQueryString(currentTarget.search.slice(1)) : {};
		while (currentTarget && currentTarget.nodeName.toUpperCase() !== "A") currentTarget = currentTarget.parentNode;
		// clear pendingRequests because we want an immediate route change
		pendingRequests = 0;
		m.route(currentTarget[m.route.mode].slice(modes[m.route.mode].length), args);
	}
	function setScroll() {
		if (m.route.mode !== "hash" && $location.hash) $location.hash = $location.hash;
		else window.scrollTo(0, 0);
	}
	function buildQueryString(object, prefix) {
		var duplicates = {};
		var str = [];
		for (var prop in object) {
			var key = prefix ? prefix + "[" + prop + "]" : prop;
			var value = object[prop];

			if (value === null) {
				str.push(encodeURIComponent(key));
			} else if (isObject(value)) {
				str.push(buildQueryString(value, key));
			} else if (isArray(value)) {
				var keys = [];
				duplicates[key] = duplicates[key] || {};
				forEach(value, function (item) {
					if (!duplicates[key][item]) {
						duplicates[key][item] = true;
						keys.push(encodeURIComponent(key) + "=" + encodeURIComponent(item));
					}
				});
				str.push(keys.join("&"));
			} else if (value !== undefined) {
				str.push(encodeURIComponent(key) + "=" + encodeURIComponent(value));
			}
		}
		return str.join("&");
	}
	function parseQueryString(str) {
		if (str === "" || str == null) return {};
		if (str.charAt(0) === "?") str = str.slice(1);

		var pairs = str.split("&"), params = {};
		forEach(pairs, function (string) {
			var pair = string.split("=");
			var key = decodeURIComponent(pair[0]);
			var value = pair.length === 2 ? decodeURIComponent(pair[1]) : null;
			if (params[key] != null) {
				if (!isArray(params[key])) params[key] = [params[key]];
				params[key].push(value);
			}
			else params[key] = value;
		});

		return params;
	}
	m.route.buildQueryString = buildQueryString;
	m.route.parseQueryString = parseQueryString;

	function reset(root) {
		var cacheKey = getCellCacheKey(root);
		clear(root.childNodes, cellCache[cacheKey]);
		cellCache[cacheKey] = undefined;
	}

	m.deferred = function () {
		var deferred = new Deferred();
		deferred.promise = propify(deferred.promise);
		return deferred;
	};
	function propify(promise, initialValue) {
		var prop = m.prop(initialValue);
		promise.then(prop);
		prop.then = function(resolve, reject) {
			return propify(promise.then(resolve, reject), initialValue);
		};
		prop["catch"] = prop.then.bind(null, null);
		return prop;
	}
	//Promiz.mithril.js | Zolmeister | MIT
	//a modified version of Promiz.js, which does not conform to Promises/A+ for two reasons:
	//1) `then` callbacks are called synchronously (because setTimeout is too slow, and the setImmediate polyfill is too big
	//2) throwing subclasses of Error cause the error to be bubbled up instead of triggering rejection (because the spec does not account for the important use case of default browser error handling, i.e. message w/ line number)
	function Deferred(successCallback, failureCallback) {
		var RESOLVING = 1, REJECTING = 2, RESOLVED = 3, REJECTED = 4;
		var self = this, state = 0, promiseValue = 0, next = [];

		self.promise = {};

		self.resolve = function(value) {
			if (!state) {
				promiseValue = value;
				state = RESOLVING;

				fire();
			}
			return this;
		};

		self.reject = function(value) {
			if (!state) {
				promiseValue = value;
				state = REJECTING;

				fire();
			}
			return this;
		};

		self.promise.then = function(successCallback, failureCallback) {
			var deferred = new Deferred(successCallback, failureCallback)
			if (state === RESOLVED) {
				deferred.resolve(promiseValue);
			}
			else if (state === REJECTED) {
				deferred.reject(promiseValue);
			}
			else {
				next.push(deferred);
			}
			return deferred.promise
		};

		function finish(type) {
			state = type || REJECTED;
			next.map(function(deferred) {
				state === RESOLVED ? deferred.resolve(promiseValue) : deferred.reject(promiseValue);
			});
		}

		function thennable(then, successCallback, failureCallback, notThennableCallback) {
			if (((promiseValue != null && isObject(promiseValue)) || isFunction(promiseValue)) && isFunction(then)) {
				try {
					// count protects against abuse calls from spec checker
					var count = 0;
					then.call(promiseValue, function(value) {
						if (count++) return;
						promiseValue = value;
						successCallback();
					}, function (value) {
						if (count++) return;
						promiseValue = value;
						failureCallback();
					});
				}
				catch (e) {
					m.deferred.onerror(e);
					promiseValue = e;
					failureCallback();
				}
			} else {
				notThennableCallback();
			}
		}

		function fire() {
			// check if it's a thenable
			var then;
			try {
				then = promiseValue && promiseValue.then;
			}
			catch (e) {
				m.deferred.onerror(e);
				promiseValue = e;
				state = REJECTING;
				return fire();
			}

			if (state === REJECTING) {
				m.deferred.onerror(promiseValue)
			}

			thennable(then, function () {
				state = RESOLVING
				fire()
			}, function () {
				state = REJECTING
				fire()
			}, function () {
				try {
					if (state === RESOLVING && isFunction(successCallback)) {
						promiseValue = successCallback(promiseValue);
					}
					else if (state === REJECTING && isFunction(failureCallback)) {
						promiseValue = failureCallback(promiseValue);
						state = RESOLVING;
					}
				}
				catch (e) {
					m.deferred.onerror(e);
					promiseValue = e;
					return finish();
				}

				if (promiseValue === self) {
					promiseValue = TypeError();
					finish();
				} else {
					thennable(then, function () {
						finish(RESOLVED);
					}, finish, function () {
						finish(state === RESOLVING && RESOLVED);
					});
				}
			});
		}
	}
	m.deferred.onerror = function(e) {
		if (type.call(e) === "[object Error]" && !e.constructor.toString().match(/ Error/)) {
			pendingRequests = 0;
			throw e;
		}
	};

	m.sync = function(args) {
		var method = "resolve";

		function synchronizer(pos, resolved) {
			return function(value) {
				results[pos] = value;
				if (!resolved) method = "reject";
				if (--outstanding === 0) {
					deferred.promise(results);
					deferred[method](results);
				}
				return value;
			};
		}

		var deferred = m.deferred();
		var outstanding = args.length;
		var results = new Array(outstanding);
		if (args.length > 0) {
			forEach(args, function (arg, i) {
				arg.then(synchronizer(i, true), synchronizer(i, false));
			});
		}
		else deferred.resolve([]);

		return deferred.promise;
	};
	function identity(value) { return value; }

	function ajax(options) {
		if (options.dataType && options.dataType.toLowerCase() === "jsonp") {
			var callbackKey = "mithril_callback_" + new Date().getTime() + "_" + (Math.round(Math.random() * 1e16)).toString(36)
			var script = $document.createElement("script");

			window[callbackKey] = function(resp) {
				script.parentNode.removeChild(script);
				options.onload({
					type: "load",
					target: {
						responseText: resp
					}
				});
				window[callbackKey] = undefined;
			};

			script.onerror = function() {
				script.parentNode.removeChild(script);

				options.onerror({
					type: "error",
					target: {
						status: 500,
						responseText: JSON.stringify({
							error: "Error making jsonp request"
						})
					}
				});
				window[callbackKey] = undefined;

				return false;
			}

			script.onload = function() {
				return false;
			};

			script.src = options.url
				+ (options.url.indexOf("?") > 0 ? "&" : "?")
				+ (options.callbackKey ? options.callbackKey : "callback")
				+ "=" + callbackKey
				+ "&" + buildQueryString(options.data || {});
			$document.body.appendChild(script);
		}
		else {
			var xhr = new window.XMLHttpRequest();
			xhr.open(options.method, options.url, true, options.user, options.password);
			xhr.onreadystatechange = function() {
				if (xhr.readyState === 4) {
					if (xhr.status >= 200 && xhr.status < 300) options.onload({type: "load", target: xhr});
					else options.onerror({type: "error", target: xhr});
				}
			};
			if (options.serialize === JSON.stringify && options.data && options.method !== "GET") {
				xhr.setRequestHeader("Content-Type", "application/json; charset=utf-8");
			}
			if (options.deserialize === JSON.parse) {
				xhr.setRequestHeader("Accept", "application/json, text/*");
			}
			if (isFunction(options.config)) {
				var maybeXhr = options.config(xhr, options);
				if (maybeXhr != null) xhr = maybeXhr;
			}

			var data = options.method === "GET" || !options.data ? "" : options.data;
			if (data && (!isString(data) && data.constructor !== window.FormData)) {
				throw new Error("Request data should be either be a string or FormData. Check the `serialize` option in `m.request`");
			}
			xhr.send(data);
			return xhr;
		}
	}

	function bindData(xhrOptions, data, serialize) {
		if (xhrOptions.method === "GET" && xhrOptions.dataType !== "jsonp") {
			var prefix = xhrOptions.url.indexOf("?") < 0 ? "?" : "&";
			var querystring = buildQueryString(data);
			xhrOptions.url = xhrOptions.url + (querystring ? prefix + querystring : "");
		}
		else xhrOptions.data = serialize(data);
		return xhrOptions;
	}

	function parameterizeUrl(url, data) {
		var tokens = url.match(/:[a-z]\w+/gi);
		if (tokens && data) {
			forEach(tokens, function (token) {
				var key = token.slice(1);
				url = url.replace(token, data[key]);
				delete data[key];
			});
		}
		return url;
	}

	m.request = function(xhrOptions) {
		if (xhrOptions.background !== true) m.startComputation();
		var deferred = new Deferred();
		var isJSONP = xhrOptions.dataType && xhrOptions.dataType.toLowerCase() === "jsonp"
		var serialize = xhrOptions.serialize = isJSONP ? identity : xhrOptions.serialize || JSON.stringify;
		var deserialize = xhrOptions.deserialize = isJSONP ? identity : xhrOptions.deserialize || JSON.parse;
		var extract = isJSONP ? function(jsonp) { return jsonp.responseText } : xhrOptions.extract || function(xhr) {
			if (xhr.responseText.length === 0 && deserialize === JSON.parse) {
				return null
			} else {
				return xhr.responseText
			}
		};
		xhrOptions.method = (xhrOptions.method || "GET").toUpperCase();
		xhrOptions.url = parameterizeUrl(xhrOptions.url, xhrOptions.data);
		xhrOptions = bindData(xhrOptions, xhrOptions.data, serialize);
		xhrOptions.onload = xhrOptions.onerror = function(e) {
			try {
				e = e || event;
				var unwrap = (e.type === "load" ? xhrOptions.unwrapSuccess : xhrOptions.unwrapError) || identity;
				var response = unwrap(deserialize(extract(e.target, xhrOptions)), e.target);
				if (e.type === "load") {
					if (isArray(response) && xhrOptions.type) {
						forEach(response, function (res, i) {
							response[i] = new xhrOptions.type(res);
						});
					} else if (xhrOptions.type) {
						response = new xhrOptions.type(response);
					}
					deferred.resolve(response)
				} else {
					deferred.reject(response)
				}

				deferred[e.type === "load" ? "resolve" : "reject"](response);
			}
			catch (e) {
				deferred.reject(e);
			}
			finally {
				if (xhrOptions.background !== true) m.endComputation()
			}
		}

		ajax(xhrOptions);
		deferred.promise = propify(deferred.promise, xhrOptions.initialValue);
		return deferred.promise;
	};

	//testing API
	m.deps = function(mock) {
		initialize(window = mock || window);
		return window;
	};
	//for internal testing only, do not use `m.deps.factory`
	m.deps.factory = app;

	return m;
})(typeof window !== "undefined" ? window : {});

if (typeof module === "object" && module != null && module.exports) module.exports = m;
else if (typeof define === "function" && define.amd) define(function() { return m });