snappymail/vendors/knockout/build/output/knockout-latest.debug.js

/*!
 * Knockout JavaScript library v3.5.1-sm
 * (c) The Knockout.js team - http://knockoutjs.com/
 * License: MIT (http://www.opensource.org/licenses/mit-license.php)
 */

(function(){
var DEBUG=true;
(window => {
    // (0, eval)('this') is a robust way of getting a reference to the global object
    // For details, see http://stackoverflow.com/questions/14119988/return-this-0-evalthis/14120023#14120023
    var document = window['document'],
        navigator = window['navigator'],
        JSON = window["JSON"],
        koExports = {};
// Internally, all KO objects are attached to koExports (even the non-exported ones whose names will be minified by the closure compiler).
// In the future, the following "ko" variable may be made distinct from "koExports" so that private objects are not externally reachable.
var ko = typeof koExports !== 'undefined' ? koExports : {};
// Google Closure Compiler helpers (used only to make the minified file smaller)
ko.exportSymbol = (koPath, object) => {
    var tokens = koPath.split(".");

    // In the future, "ko" may become distinct from "koExports" (so that non-exported objects are not reachable)
    // At that point, "target" would be set to: (typeof koExports !== "undefined" ? koExports : ko)
    var target = ko;

    for (var i = 0; i < tokens.length - 1; i++)
        target = target[tokens[i]];
    target[tokens[tokens.length - 1]] = object;
};
ko.exportProperty = (owner, publicName, object) => owner[publicName] = object;
ko.version = "3.5.1-sm";

ko.exportSymbol('version', ko.version);
ko.utils = (() => {

    const
        arrayCall = (name, arr, p1, p2) => Array.prototype[name].call(arr, p1, p2),
        objectForEach = (obj, action) => obj && Object.entries(obj).forEach(prop => action(prop[0], prop[1])),
        extend = (target, source) => {
            source && Object.entries(source).forEach(prop => target[prop[0]] = prop[1]);
            return target;
        },
        setPrototypeOf = (obj, proto) => {
            obj.__proto__ = proto;
            return obj;
        },
        // For details on the pattern for changing node classes
        // see: https://github.com/knockout/knockout/issues/1597
        toggleDomNodeCssClass = (node, classNames, shouldHaveClass) => {
            if (classNames) {
                var addOrRemoveFn = shouldHaveClass ? 'add' : 'remove';
                classNames.split(/\s+/).forEach(className =>
                    node.classList[addOrRemoveFn](className)
                );
            }
        };

    var canSetPrototype = ({ __proto__: [] } instanceof Array);

    return {
        arrayForEach: (array, action, actionOwner) =>
            arrayCall('forEach', array, action, actionOwner),

        arrayIndexOf: (array, item) =>
            arrayCall('indexOf', array, item),

        arrayFirst: (array, predicate, predicateOwner) =>
            arrayCall('find', array, (e, i, a) => predicate.call(predicateOwner, e, i, a)),

        arrayRemoveItem: (array, itemToRemove) => {
            var index = ko.utils.arrayIndexOf(array, itemToRemove);
            if (index > 0) {
                array.splice(index, 1);
            }
            else if (index === 0) {
                array.shift();
            }
        },

        arrayPushAll: (array, valuesToPush) => {
            if (valuesToPush instanceof Array)
                array.push.apply(array, valuesToPush);
            else
                for (var i = 0, j = valuesToPush.length; i < j; i++)
                    array.push(valuesToPush[i]);
            return array;
        },

        canSetPrototype: canSetPrototype,

        extend: extend,

        setPrototypeOf: setPrototypeOf,

        setPrototypeOfOrExtend: canSetPrototype ? setPrototypeOf : extend,

        objectForEach: objectForEach,

        objectMap: (source, mapping, mappingOwner) => {
            if (!source)
                return source;
            var target = {};
            Object.entries(source).forEach(prop =>
                target[prop[0]] = mapping.call(mappingOwner, prop[1], prop[0], source)
            );
            return target;
        },

        emptyDomNode: domNode => {
            while (domNode.firstChild) {
                ko.removeNode(domNode.firstChild);
            }
        },

        moveCleanedNodesToContainerElement: nodes => {
            // Ensure it's a real array, as we're about to reparent the nodes and
            // we don't want the underlying collection to change while we're doing that.
            var nodesArray = ko.utils.makeArray(nodes);
            var templateDocument = (nodesArray[0] && nodesArray[0].ownerDocument) || document;

            var container = templateDocument.createElement('div');
            nodes.forEach(node => container.append(ko.cleanNode(node)));
            return container;
        },

        cloneNodes: (nodesArray, shouldCleanNodes) =>
            arrayCall('map', nodesArray, shouldCleanNodes
                ? node => ko.cleanNode(node.cloneNode(true))
                : node => node.cloneNode(true)
            ),

        setDomNodeChildren: (domNode, childNodes) => {
            ko.utils.emptyDomNode(domNode);
            childNodes && domNode.append.apply(domNode, childNodes);
        },

        fixUpContinuousNodeArray: (continuousNodeArray, parentNode) => {
            // Before acting on a set of nodes that were previously outputted by a template function, we have to reconcile
            // them against what is in the DOM right now. It may be that some of the nodes have already been removed, or that
            // new nodes might have been inserted in the middle, for example by a binding. Also, there may previously have been
            // leading comment nodes (created by rewritten string-based templates) that have since been removed during binding.
            // So, this function translates the old "map" output array into its best guess of the set of current DOM nodes.
            //
            // Rules:
            //   [A] Any leading nodes that have been removed should be ignored
            //       These most likely correspond to memoization nodes that were already removed during binding
            //       See https://github.com/knockout/knockout/pull/440
            //   [B] Any trailing nodes that have been remove should be ignored
            //       This prevents the code here from adding unrelated nodes to the array while processing rule [C]
            //       See https://github.com/knockout/knockout/pull/1903
            //   [C] We want to output a continuous series of nodes. So, ignore any nodes that have already been removed,
            //       and include any nodes that have been inserted among the previous collection

            if (continuousNodeArray.length) {
                // The parent node can be a virtual element; so get the real parent node
                parentNode = (parentNode.nodeType === 8 && parentNode.parentNode) || parentNode;

                // Rule [A]
                while (continuousNodeArray.length && continuousNodeArray[0].parentNode !== parentNode)
                    continuousNodeArray.splice(0, 1);

                // Rule [B]
                while (continuousNodeArray.length > 1
                    && continuousNodeArray[continuousNodeArray.length - 1].parentNode !== parentNode)
                    continuousNodeArray.length--;

                // Rule [C]
                if (continuousNodeArray.length > 1) {
                    var current = continuousNodeArray[0], last = continuousNodeArray[continuousNodeArray.length - 1];
                    // Replace with the actual new continuous node set
                    continuousNodeArray.length = 0;
                    while (current !== last) {
                        continuousNodeArray.push(current);
                        current = current.nextSibling;
                    }
                    continuousNodeArray.push(last);
                }
            }
            return continuousNodeArray;
        },

        stringTrim: string => string == null ? '' :
                string.trim ?
                    string.trim() :
                    string.toString().replace(/^[\s\xa0]+|[\s\xa0]+$/g, ''),

        stringStartsWith: (string, startsWith) => {
            string = string || "";
            if (startsWith.length > string.length)
                return false;
            return string.substring(0, startsWith.length) === startsWith;
        },

        domNodeIsContainedBy: (node, containedByNode) =>
            containedByNode.contains(node.nodeType !== 1 ? node.parentNode : node),

        domNodeIsAttachedToDocument: node => ko.utils.domNodeIsContainedBy(node, node.ownerDocument.documentElement),

        // For HTML elements, tagName will always be upper case; for XHTML elements, it'll be lower case.
        // Possible future optimization: If we know it's an element from an XHTML document (not HTML),
        // we don't need to do the .toLowerCase() as it will always be lower case anyway.
        tagNameLower: element => element && element.tagName && element.tagName.toLowerCase(),

        catchFunctionErrors: delegate => {
            return ko['onError'] ? function () {
                try {
                    return delegate.apply(this, arguments);
                } catch (e) {
                    ko['onError'] && ko['onError'](e);
                    throw e;
                }
            } : delegate;
        },

        setTimeout: (handler, timeout) => setTimeout(ko.utils.catchFunctionErrors(handler), timeout),

        deferError: error => setTimeout(() => {
                ko['onError'] && ko['onError'](error);
                throw error;
            }, 0),

        registerEventHandler: (element, eventType, handler) => {
            var wrappedHandler = ko.utils.catchFunctionErrors(handler);

            element.addEventListener(eventType, wrappedHandler, false);
        },

        triggerEvent: (element, eventType) => {
            if (!(element && element.nodeType))
                throw new Error("element must be a DOM node when calling triggerEvent");

            element.dispatchEvent(new Event(eventType));
        },

        unwrapObservable: value => ko.isObservable(value) ? value() : value,

        peekObservable: value => ko.isObservable(value) ? value.peek() : value,

        toggleDomNodeCssClass: toggleDomNodeCssClass,

        setTextContent: (element, textContent) =>
            element.textContent = ko.utils.unwrapObservable(textContent) || "",

        makeArray: arrayLikeObject => Array['from'](arrayLikeObject)
    }
})();

ko.exportSymbol('utils', ko.utils);
ko.exportSymbol('unwrap', ko.utils.unwrapObservable); // Convenient shorthand, because this is used so commonly

ko.utils.domData = new (function () {
    var uniqueId = 0;
    var dataStoreKeyExpandoPropertyName = "__ko__" + (Date.now());

    var
    // We considered using WeakMap, but it has a problem in IE 11 and Edge that prevents using
    // it cross-window, so instead we just store the data directly on the node.
    // See https://github.com/knockout/knockout/issues/2141
    getDataForNode = (node, createIfNotFound) => {
        var dataForNode = node[dataStoreKeyExpandoPropertyName];
        if (!dataForNode && createIfNotFound) {
            dataForNode = node[dataStoreKeyExpandoPropertyName] = {};
        }
        return dataForNode;
    },
    clear = node => {
        if (node[dataStoreKeyExpandoPropertyName]) {
            delete node[dataStoreKeyExpandoPropertyName];
            return true; // Exposing "did clean" flag purely so specs can infer whether things have been cleaned up as intended
        }
        return false;
    };

    return {
        get: (node, key) => {
            var dataForNode = getDataForNode(node, false);
            return dataForNode && dataForNode[key];
        },
        set: (node, key, value) => {
            // Make sure we don't actually create a new domData key if we are actually deleting a value
            var dataForNode = getDataForNode(node, value !== undefined /* createIfNotFound */);
            dataForNode && (dataForNode[key] = value);
        },
        getOrSet: (node, key, value) => {
            var dataForNode = getDataForNode(node, true /* createIfNotFound */);
            return dataForNode[key] || (dataForNode[key] = value);
        },
        clear: clear,

        nextKey: () => (uniqueId++) + dataStoreKeyExpandoPropertyName
    };
})();

ko.utils.domNodeDisposal = new (function () {
    var domDataKey = ko.utils.domData.nextKey();
    var cleanableNodeTypes = { 1: true, 8: true, 9: true };       // Element, Comment, Document
    var cleanableNodeTypesWithDescendants = { 1: true, 9: true }; // Element, Document

    function getDisposeCallbacksCollection(node, createIfNotFound) {
        var allDisposeCallbacks = ko.utils.domData.get(node, domDataKey);
        if ((allDisposeCallbacks === undefined) && createIfNotFound) {
            allDisposeCallbacks = [];
            ko.utils.domData.set(node, domDataKey, allDisposeCallbacks);
        }
        return allDisposeCallbacks;
    }
    function destroyCallbacksCollection(node) {
        ko.utils.domData.set(node, domDataKey, undefined);
    }

    function cleanSingleNode(node) {
        // Run all the dispose callbacks
        var callbacks = getDisposeCallbacksCollection(node, false);
        if (callbacks) {
            callbacks = callbacks.slice(0); // Clone, as the array may be modified during iteration (typically, callbacks will remove themselves)
            for (var i = 0; i < callbacks.length; i++)
                callbacks[i](node);
        }

        // Erase the DOM data
        ko.utils.domData.clear(node);

        // Clear any immediate-child comment nodes, as these wouldn't have been found by
        // node.getElementsByTagName("*") in cleanNode() (comment nodes aren't elements)
        if (cleanableNodeTypesWithDescendants[node.nodeType]) {
            cleanNodesInList(node.childNodes, true/*onlyComments*/);
        }
    }

    function cleanNodesInList(nodeList, onlyComments) {
        var cleanedNodes = [], lastCleanedNode;
        for (var i = 0; i < nodeList.length; i++) {
            if (!onlyComments || nodeList[i].nodeType === 8) {
                cleanSingleNode(cleanedNodes[cleanedNodes.length] = lastCleanedNode = nodeList[i]);
                if (nodeList[i] !== lastCleanedNode) {
                    while (i-- && ko.utils.arrayIndexOf(cleanedNodes, nodeList[i]) == -1);
                }
            }
        }
    }

    return {
        addDisposeCallback : (node, callback) => {
            if (typeof callback != "function")
                throw new Error("Callback must be a function");
            getDisposeCallbacksCollection(node, true).push(callback);
        },

        removeDisposeCallback : (node, callback) => {
            var callbacksCollection = getDisposeCallbacksCollection(node, false);
            if (callbacksCollection) {
                ko.utils.arrayRemoveItem(callbacksCollection, callback);
                if (callbacksCollection.length == 0)
                    destroyCallbacksCollection(node);
            }
        },

        cleanNode : node => {
            ko.dependencyDetection.ignore(() => {
                // First clean this node, where applicable
                if (cleanableNodeTypes[node.nodeType]) {
                    cleanSingleNode(node);

                    // ... then its descendants, where applicable
                    if (cleanableNodeTypesWithDescendants[node.nodeType]) {
                        cleanNodesInList(node.getElementsByTagName("*"));
                    }
                }
            });

            return node;
        },

        removeNode : node => {
            ko.cleanNode(node);
            if (node.parentNode)
                node.parentNode.removeChild(node);
        }
    };
})();
ko.cleanNode = ko.utils.domNodeDisposal.cleanNode; // Shorthand name for convenience
ko.removeNode = ko.utils.domNodeDisposal.removeNode; // Shorthand name for convenience
ko.exportSymbol('utils.domNodeDisposal', ko.utils.domNodeDisposal);
ko.exportSymbol('utils.domNodeDisposal.addDisposeCallback', ko.utils.domNodeDisposal.addDisposeCallback);
(() => {
    var none = [0, "", ""],
        table = [1, "<table>", "</table>"],
        tbody = [2, "<table><tbody>", "</tbody></table>"],
        tr = [3, "<table><tbody><tr>", "</tr></tbody></table>"],
        select = [1, "<select multiple='multiple'>", "</select>"],
        lookup = {
            'thead': table,
            'tbody': table,
            'tfoot': table,
            'tr': tbody,
            'td': tr,
            'th': tr,
            'option': select,
            'optgroup': select
        };

    function getWrap(tags) {
        var m = tags.match(/^(?:<!--.*?-->\s*?)*?<([a-z]+)[\s>]/);
        return (m && lookup[m[1]]) || none;
    }

    function simpleHtmlParse(html, documentContext) {
        documentContext || (documentContext = document);
        var windowContext = documentContext['parentWindow'] || documentContext['defaultView'] || window;

        // Based on jQuery's "clean" function, but only accounting for table-related elements.

        // Trim whitespace, otherwise indexOf won't work as expected
        var tags = ko.utils.stringTrim(html).toLowerCase(), div = documentContext.createElement("div"),
            wrap = getWrap(tags),
            depth = wrap[0];

        // Go to html and back, then peel off extra wrappers
        // Note that we always prefix with some dummy text, because otherwise, IE<9 will strip out leading comment nodes in descendants. Total madness.
        var markup = "ignored<div>" + wrap[1] + html + wrap[2] + "</div>";
        if (typeof windowContext['innerShiv'] == "function") {
            // Note that innerShiv is deprecated in favour of html5shiv. We should consider adding
            // support for html5shiv (except if no explicit support is needed, e.g., if html5shiv
            // somehow shims the native APIs so it just works anyway)
            div.append(windowContext['innerShiv'](markup));
        } else {
            div.innerHTML = markup;
        }

        // Move to the right depth
        while (depth--)
            div = div.lastChild;

        return ko.utils.makeArray(div.lastChild.childNodes);
    }

    ko.utils.parseHtmlFragment = (html, documentContext) =>
        simpleHtmlParse(html, documentContext);  // ... otherwise, this simple logic will do in most common cases.

    ko.utils.parseHtmlForTemplateNodes = (html, documentContext) => {
        var nodes = ko.utils.parseHtmlFragment(html, documentContext);
        return (nodes.length && nodes[0].parentElement) || ko.utils.moveCleanedNodesToContainerElement(nodes);
    };

    ko.utils.setHtml = (node, html) => {
        ko.utils.emptyDomNode(node);

        // There's no legitimate reason to display a stringified observable without unwrapping it, so we'll unwrap it
        html = ko.utils.unwrapObservable(html);

        if ((html !== null) && (html !== undefined)) {
            if (typeof html != 'string')
                html = html.toString();

            // jQuery contains a lot of sophisticated code to parse arbitrary HTML fragments,
            // for example <tr> elements which are not normally allowed to exist on their own.
            // If you've referenced jQuery we'll use that rather than duplicating its code.
            // ... otherwise, use KO's own parsing logic.
            var parsedNodes = ko.utils.parseHtmlFragment(html, node.ownerDocument);
            for (var i = 0; i < parsedNodes.length; i++)
                node.appendChild(parsedNodes[i]);
        }
    };
})();
ko.tasks = (() => {
    var taskQueue = [],
        taskQueueLength = 0,
        nextHandle = 1,
        nextIndexToProcess = 0,

    // Chrome 27+, Firefox 14+, IE 11+, Opera 15+, Safari 6.1+
    // From https://github.com/petkaantonov/bluebird * Copyright (c) 2014 Petka Antonov * License: MIT
    scheduler = (callback => {
        var div = document.createElement("div");
        new MutationObserver(callback).observe(div, {attributes: true});
        return () => div.classList.toggle("foo");
    })(scheduledProcess);

    function processTasks() {
        if (taskQueueLength) {
            // Each mark represents the end of a logical group of tasks and the number of these groups is
            // limited to prevent unchecked recursion.
            var mark = taskQueueLength, countMarks = 0;

            // nextIndexToProcess keeps track of where we are in the queue; processTasks can be called recursively without issue
            for (var task; nextIndexToProcess < taskQueueLength; ) {
                if (task = taskQueue[nextIndexToProcess++]) {
                    if (nextIndexToProcess > mark) {
                        if (++countMarks >= 5000) {
                            nextIndexToProcess = taskQueueLength;   // skip all tasks remaining in the queue since any of them could be causing the recursion
                            ko.utils.deferError(Error("'Too much recursion' after processing " + countMarks + " task groups."));
                            break;
                        }
                        mark = taskQueueLength;
                    }
                    try {
                        task();
                    } catch (ex) {
                        ko.utils.deferError(ex);
                    }
                }
            }
        }
    }

    function scheduledProcess() {
        processTasks();

        // Reset the queue
        nextIndexToProcess = taskQueueLength = taskQueue.length = 0;
    }

    var tasks = {
        schedule: func => {
            if (!taskQueueLength) {
                scheduler(scheduledProcess);
            }

            taskQueue[taskQueueLength++] = func;
            return nextHandle++;
        },

        cancel: handle => {
            var index = handle - (nextHandle - taskQueueLength);
            if (index >= nextIndexToProcess && index < taskQueueLength) {
                taskQueue[index] = null;
            }
        }
    };

    return tasks;
})();

ko.exportSymbol('tasks', ko.tasks);
ko.extenders = {
    'throttle': (target, timeout) => {
        // Throttling means two things:

        // (1) For dependent observables, we throttle *evaluations* so that, no matter how fast its dependencies
        //     notify updates, the target doesn't re-evaluate (and hence doesn't notify) faster than a certain rate
        target['throttleEvaluation'] = timeout;

        // (2) For writable targets (observables, or writable dependent observables), we throttle *writes*
        //     so the target cannot change value synchronously or faster than a certain rate
        var writeTimeoutInstance = null;
        return ko.computed({
            'read': target,
            'write': value => {
                clearTimeout(writeTimeoutInstance);
                writeTimeoutInstance = ko.utils.setTimeout(() => target(value), timeout);
            }
        });
    },

    'rateLimit': (target, options) => {
        var timeout, method, limitFunction;

        if (typeof options == 'number') {
            timeout = options;
        } else {
            timeout = options['timeout'];
            method = options['method'];
        }

        limitFunction = typeof method == 'function' ? method : method == 'notifyWhenChangesStop' ?  debounce : throttle;
        target.limit(callback => limitFunction(callback, timeout, options));
    },

    'notify': (target, notifyWhen) => {
        target["equalityComparer"] = notifyWhen == "always" ?
            null :  // null equalityComparer means to always notify
            valuesArePrimitiveAndEqual;
    }
};

var primitiveTypes = { 'undefined':1, 'boolean':1, 'number':1, 'string':1 };
function valuesArePrimitiveAndEqual(a, b) {
    var oldValueIsPrimitive = (a === null) || (typeof(a) in primitiveTypes);
    return oldValueIsPrimitive ? (a === b) : false;
}

function throttle(callback, timeout) {
    var timeoutInstance;
    return () => {
        if (!timeoutInstance) {
            timeoutInstance = ko.utils.setTimeout(() => {
                timeoutInstance = undefined;
                callback();
            }, timeout);
        }
    };
}

function debounce(callback, timeout) {
    var timeoutInstance;
    return () => {
        clearTimeout(timeoutInstance);
        timeoutInstance = ko.utils.setTimeout(callback, timeout);
    };
}

function applyExtenders(requestedExtenders) {
    var target = this;
    if (requestedExtenders) {
        ko.utils.objectForEach(requestedExtenders, (key, value) => {
            var extenderHandler = ko.extenders[key];
            if (typeof extenderHandler == 'function') {
                target = extenderHandler(target, value) || target;
            }
        });
    }
    return target;
}

ko.exportSymbol('extenders', ko.extenders);

ko.subscription = function (target, callback, disposeCallback) {
    this._target = target;
    this._callback = callback;
    this._disposeCallback = disposeCallback;
    this._isDisposed = false;
    this._node = null;
    this._domNodeDisposalCallback = null;
    ko.exportProperty(this, 'dispose', this.dispose);
    ko.exportProperty(this, 'disposeWhenNodeIsRemoved', this.disposeWhenNodeIsRemoved);
};
ko.subscription.prototype.dispose = function () {
    var self = this;
    if (!self._isDisposed) {
        if (self._domNodeDisposalCallback) {
            ko.utils.domNodeDisposal.removeDisposeCallback(self._node, self._domNodeDisposalCallback);
        }
        self._isDisposed = true;
        self._disposeCallback();

        self._target = self._callback = self._disposeCallback = self._node = self._domNodeDisposalCallback = null;
    }
};
ko.subscription.prototype.disposeWhenNodeIsRemoved = function (node) {
    this._node = node;
    ko.utils.domNodeDisposal.addDisposeCallback(node, this._domNodeDisposalCallback = this.dispose.bind(this));
};

ko.subscribable = function () {
    ko.utils.setPrototypeOfOrExtend(this, ko_subscribable_fn);
    ko_subscribable_fn.init(this);
}

var defaultEvent = "change";

var ko_subscribable_fn = {
    init: instance => {
        instance._subscriptions = { "change": [] };
        instance._versionNumber = 1;
    },

    subscribe: function (callback, callbackTarget, event) {
        var self = this;

        event = event || defaultEvent;
        var boundCallback = callbackTarget ? callback.bind(callbackTarget) : callback;

        var subscription = new ko.subscription(self, boundCallback, () => {
            ko.utils.arrayRemoveItem(self._subscriptions[event], subscription);
            if (self.afterSubscriptionRemove)
                self.afterSubscriptionRemove(event);
        });

        if (self.beforeSubscriptionAdd)
            self.beforeSubscriptionAdd(event);

        if (!self._subscriptions[event])
            self._subscriptions[event] = [];
        self._subscriptions[event].push(subscription);

        return subscription;
    },

    "notifySubscribers": function (valueToNotify, event) {
        event = event || defaultEvent;
        if (event === defaultEvent) {
            this.updateVersion();
        }
        if (this.hasSubscriptionsForEvent(event)) {
            var subs = event === defaultEvent && this._changeSubscriptions || this._subscriptions[event].slice(0);
            try {
                ko.dependencyDetection.begin(); // Begin suppressing dependency detection (by setting the top frame to undefined)
                for (var i = 0, subscription; subscription = subs[i]; ++i) {
                    // In case a subscription was disposed during the arrayForEach cycle, check
                    // for isDisposed on each subscription before invoking its callback
                    if (!subscription._isDisposed)
                        subscription._callback(valueToNotify);
                }
            } finally {
                ko.dependencyDetection.end(); // End suppressing dependency detection
            }
        }
    },

    getVersion: function () {
        return this._versionNumber;
    },

    hasChanged: function (versionToCheck) {
        return this.getVersion() !== versionToCheck;
    },

    updateVersion: function () {
        ++this._versionNumber;
    },

    limit: function(limitFunction) {
        var self = this, selfIsObservable = ko.isObservable(self),
            ignoreBeforeChange, notifyNextChange, previousValue, pendingValue, didUpdate,
            beforeChange = 'beforeChange';

        if (!self._origNotifySubscribers) {
            self._origNotifySubscribers = self["notifySubscribers"];
            // Moved out of "limit" to avoid the extra closure
            self["notifySubscribers"] = function(value, event) {
                if (!event || event === defaultEvent) {
                    this._limitChange(value);
                } else if (event === 'beforeChange') {
                    this._limitBeforeChange(value);
                } else {
                    this._origNotifySubscribers(value, event);
                }
            }
        }

        var finish = limitFunction(() => {
            self._notificationIsPending = false;

            // If an observable provided a reference to itself, access it to get the latest value.
            // This allows computed observables to delay calculating their value until needed.
            if (selfIsObservable && pendingValue === self) {
                pendingValue = self._evalIfChanged ? self._evalIfChanged() : self();
            }
            var shouldNotify = notifyNextChange || (didUpdate && self.isDifferent(previousValue, pendingValue));

            didUpdate = notifyNextChange = ignoreBeforeChange = false;

            if (shouldNotify) {
                self._origNotifySubscribers(previousValue = pendingValue);
            }
        });

        self._limitChange = (value, isDirty) => {
            if (!isDirty || !self._notificationIsPending) {
                didUpdate = !isDirty;
            }
            self._changeSubscriptions = self._subscriptions[defaultEvent].slice(0);
            self._notificationIsPending = ignoreBeforeChange = true;
            pendingValue = value;
            finish();
        };
        self._limitBeforeChange = value => {
            if (!ignoreBeforeChange) {
                previousValue = value;
                self._origNotifySubscribers(value, beforeChange);
            }
        };
        self._recordUpdate = () => {
            didUpdate = true;
        };
        self._notifyNextChangeIfValueIsDifferent = () => {
            if (self.isDifferent(previousValue, self.peek(true /*evaluate*/))) {
                notifyNextChange = true;
            }
        };
    },

    hasSubscriptionsForEvent: function(event) {
        return this._subscriptions[event] && this._subscriptions[event].length;
    },

    getSubscriptionsCount: function (event) {
        if (event) {
            return this._subscriptions[event] && this._subscriptions[event].length || 0;
        }
        var total = 0;
        ko.utils.objectForEach(this._subscriptions, (eventName, subscriptions) =>
            total += subscriptions.length
        );
        return total;
    },

    isDifferent: function(oldValue, newValue) {
        return !this['equalityComparer'] || !this['equalityComparer'](oldValue, newValue);
    },

    toString: () => '[object Object]',

    extend: applyExtenders
};

ko.exportProperty(ko_subscribable_fn, 'init', ko_subscribable_fn.init);
ko.exportProperty(ko_subscribable_fn, 'subscribe', ko_subscribable_fn.subscribe);
ko.exportProperty(ko_subscribable_fn, 'extend', ko_subscribable_fn.extend);
ko.exportProperty(ko_subscribable_fn, 'getSubscriptionsCount', ko_subscribable_fn.getSubscriptionsCount);

// For browsers that support proto assignment, we overwrite the prototype of each
// observable instance. Since observables are functions, we need Function.prototype
// to still be in the prototype chain.
if (ko.utils.canSetPrototype) {
    ko.utils.setPrototypeOf(ko_subscribable_fn, Function.prototype);
}

ko.subscribable['fn'] = ko_subscribable_fn;


ko.isSubscribable = instance =>
    instance != null && typeof instance.subscribe == "function" && typeof instance["notifySubscribers"] == "function";

ko.computedContext = ko.dependencyDetection = (() => {
    var outerFrames = [],
        currentFrame,
        lastId = 0;

    function begin(options) {
        outerFrames.push(currentFrame);
        currentFrame = options;
    }

    function end() {
        currentFrame = outerFrames.pop();
    }

    return {
        begin: begin,

        end: end,

        registerDependency: subscribable => {
            if (currentFrame) {
                if (!ko.isSubscribable(subscribable))
                    throw new Error("Only subscribable things can act as dependencies");
                currentFrame.callback.call(currentFrame.callbackTarget, subscribable, subscribable._id || (subscribable._id = ++lastId));
            }
        },

        ignore: (callback, callbackTarget, callbackArgs) => {
            try {
                begin();
                return callback.apply(callbackTarget, callbackArgs || []);
            } finally {
                end();
            }
        },

        getDependenciesCount: () => {
            if (currentFrame)
                return currentFrame.computed.getDependenciesCount();
        },

        getDependencies: () => {
            if (currentFrame)
                return currentFrame.computed.getDependencies();
        },

        isInitial: () => {
            if (currentFrame)
                return currentFrame.isInitial;
        },

        computed: () => {
            if (currentFrame)
                return currentFrame.computed;
        }
    };
})();
var observableLatestValue = Symbol('_latestValue');

ko.observable = initialValue => {
    function observable() {
        if (arguments.length > 0) {
            // Write

            // Ignore writes if the value hasn't changed
            if (observable.isDifferent(observable[observableLatestValue], arguments[0])) {
                observable.valueWillMutate();
                observable[observableLatestValue] = arguments[0];
                observable.valueHasMutated();
            }
            return this; // Permits chained assignments
        }
        else {
            // Read
            ko.dependencyDetection.registerDependency(observable); // The caller only needs to be notified of changes if they did a "read" operation
            return observable[observableLatestValue];
        }
    }

    observable[observableLatestValue] = initialValue;

    // Inherit from 'subscribable'
    if (!ko.utils.canSetPrototype) {
        // 'subscribable' won't be on the prototype chain unless we put it there directly
        ko.utils.extend(observable, ko.subscribable['fn']);
    }
    ko.subscribable['fn'].init(observable);

    // Inherit from 'observable'
    ko.utils.setPrototypeOfOrExtend(observable, observableFn);

    return observable;
}

// Define prototype for observables
var observableFn = {
    'toJSON': function() {
        let value = this[observableLatestValue];
        return value.toJSON ? value.toJSON() : value;
    },
    'equalityComparer': valuesArePrimitiveAndEqual,
    peek: function() { return this[observableLatestValue]; },
    valueHasMutated: function () {
        this['notifySubscribers'](this[observableLatestValue], 'spectate');
        this['notifySubscribers'](this[observableLatestValue]);
    },
    valueWillMutate: function () { this['notifySubscribers'](this[observableLatestValue], 'beforeChange'); }
};

// Note that for browsers that don't support proto assignment, the
// inheritance chain is created manually in the ko.observable constructor
if (ko.utils.canSetPrototype) {
    ko.utils.setPrototypeOf(observableFn, ko.subscribable['fn']);
}

var protoProperty = ko.observable.protoProperty = '__ko_proto__';
observableFn[protoProperty] = ko.observable;

ko.isObservable = instance => {
    var proto = typeof instance == 'function' && instance[protoProperty];
    if (proto && proto !== observableFn[protoProperty] && proto !== ko.computed['fn'][protoProperty]) {
        throw Error("Invalid object that looks like an observable; possibly from another Knockout instance");
    }
    return !!proto;
};

ko.isWriteableObservable = instance => {
    return (typeof instance == 'function' && (
        (instance[protoProperty] === observableFn[protoProperty]) ||  // Observable
        (instance[protoProperty] === ko.computed['fn'][protoProperty] && instance.hasWriteFunction)));   // Writable computed observable
};

ko.exportSymbol('observable', ko.observable);
ko.exportSymbol('isObservable', ko.isObservable);
ko.exportSymbol('observable.fn', observableFn);
ko.exportProperty(observableFn, 'valueHasMutated', observableFn.valueHasMutated);
ko.observableArray = initialValues => {
    initialValues = initialValues || [];

    if (typeof initialValues != 'object' || !('length' in initialValues))
        throw new Error("The argument passed when initializing an observable array must be an array, or null, or undefined.");

    var result = ko.observable(initialValues);
    ko.utils.setPrototypeOfOrExtend(result, ko.observableArray['fn']);
    return result.extend({'trackArrayChanges':true});
};

ko.observableArray['fn'] = {
    'remove': function (valueOrPredicate) {
        var underlyingArray = this.peek();
        var removedValues = [];
        var predicate = typeof valueOrPredicate == "function" && !ko.isObservable(valueOrPredicate) ? valueOrPredicate : function (value) { return value === valueOrPredicate; };
        for (var i = 0; i < underlyingArray.length; i++) {
            var value = underlyingArray[i];
            if (predicate(value)) {
                if (removedValues.length === 0) {
                    this.valueWillMutate();
                }
                if (underlyingArray[i] !== value) {
                    throw Error("Array modified during remove; cannot remove item");
                }
                removedValues.push(value);
                underlyingArray.splice(i, 1);
                i--;
            }
        }
        if (removedValues.length) {
            this.valueHasMutated();
        }
        return removedValues;
    },

    'removeAll': function (arrayOfValues) {
        // If you passed zero args, we remove everything
        if (arrayOfValues === undefined) {
            var underlyingArray = this.peek();
            var allValues = underlyingArray.slice(0);
            this.valueWillMutate();
            underlyingArray.splice(0, underlyingArray.length);
            this.valueHasMutated();
            return allValues;
        }
        // If you passed an arg, we interpret it as an array of entries to remove
        if (!arrayOfValues)
            return [];
        return this['remove'](function (value) {
            return ko.utils.arrayIndexOf(arrayOfValues, value) >= 0;
        });
    },

    'indexOf': function (item) {
        return ko.utils.arrayIndexOf(this(), item);
    }
};

// Note that for browsers that don't support proto assignment, the
// inheritance chain is created manually in the ko.observableArray constructor
if (ko.utils.canSetPrototype) {
    ko.utils.setPrototypeOf(ko.observableArray['fn'], ko.observable['fn']);
}

// Populate ko.observableArray.fn with read/write functions from native arrays
// Important: Do not add any additional functions here that may reasonably be used to *read* data from the array
// because we'll eval them without causing subscriptions, so ko.computed output could end up getting stale
["pop", "push", "reverse", "shift", "sort", "splice", "unshift"].forEach(methodName => {
    ko.observableArray['fn'][methodName] = function () {
        // Use "peek" to avoid creating a subscription in any computed that we're executing in the context of
        // (for consistency with mutating regular observables)
        var underlyingArray = this.peek();
        this.valueWillMutate();
        this.cacheDiffForKnownOperation(underlyingArray, methodName, arguments);
        var methodCallResult = underlyingArray[methodName].apply(underlyingArray, arguments);
        this.valueHasMutated();
        // The native sort and reverse methods return a reference to the array, but it makes more sense to return the observable array instead.
        return methodCallResult === underlyingArray ? this : methodCallResult;
    };
});

// Populate ko.observableArray.fn with read-only functions from native arrays
["slice"].forEach(methodName => {
    ko.observableArray['fn'][methodName] = function () {
        var underlyingArray = this();
        return underlyingArray[methodName].apply(underlyingArray, arguments);
    };
});

ko.isObservableArray = instance => {
    return ko.isObservable(instance)
        && typeof instance["remove"] == "function"
        && typeof instance["push"] == "function";
};

ko.exportSymbol('observableArray', ko.observableArray);
ko.exportSymbol('isObservableArray', ko.isObservableArray);
var arrayChangeEventName = 'arrayChange';
ko.extenders['trackArrayChanges'] = (target, options) => {
    // Use the provided options--each call to trackArrayChanges overwrites the previously set options
    target.compareArrayOptions = {};
    if (options && typeof options == "object") {
        ko.utils.extend(target.compareArrayOptions, options);
    }
    target.compareArrayOptions['sparse'] = true;

    // Only modify the target observable once
    if (target.cacheDiffForKnownOperation) {
        return;
    }
    var trackingChanges = false,
        cachedDiff = null,
        changeSubscription,
        spectateSubscription,
        pendingChanges = 0,
        previousContents,
        underlyingBeforeSubscriptionAddFunction = target.beforeSubscriptionAdd,
        underlyingAfterSubscriptionRemoveFunction = target.afterSubscriptionRemove;

    // Watch "subscribe" calls, and for array change events, ensure change tracking is enabled
    target.beforeSubscriptionAdd = event => {
        if (underlyingBeforeSubscriptionAddFunction) {
            underlyingBeforeSubscriptionAddFunction.call(target, event);
        }
        if (event === arrayChangeEventName) {
            trackChanges();
        }
    };
    // Watch "dispose" calls, and for array change events, ensure change tracking is disabled when all are disposed
    target.afterSubscriptionRemove = event => {
        if (underlyingAfterSubscriptionRemoveFunction) {
            underlyingAfterSubscriptionRemoveFunction.call(target, event);
        }
        if (event === arrayChangeEventName && !target.hasSubscriptionsForEvent(arrayChangeEventName)) {
            if (changeSubscription) {
                changeSubscription.dispose();
            }
            if (spectateSubscription) {
                spectateSubscription.dispose();
            }
            spectateSubscription = changeSubscription = null;
            trackingChanges = false;
            previousContents = undefined;
        }
    };

    function trackChanges() {
        if (trackingChanges) {
            // Whenever there's a new subscription and there are pending notifications, make sure all previous
            // subscriptions are notified of the change so that all subscriptions are in sync.
            notifyChanges();
            return;
        }

        trackingChanges = true;

        // Track how many times the array actually changed value
        spectateSubscription = target.subscribe(() => ++pendingChanges, null, "spectate");

        // Each time the array changes value, capture a clone so that on the next
        // change it's possible to produce a diff
        previousContents = [].concat(target.peek() || []);
        cachedDiff = null;
        changeSubscription = target.subscribe(notifyChanges);

        function notifyChanges() {
            if (pendingChanges) {
                // Make a copy of the current contents and ensure it's an array
                var currentContents = [].concat(target.peek() || []), changes;

                // Compute the diff and issue notifications, but only if someone is listening
                if (target.hasSubscriptionsForEvent(arrayChangeEventName)) {
                    changes = getChanges(previousContents, currentContents);
                }

                // Eliminate references to the old, removed items, so they can be GCed
                previousContents = currentContents;
                cachedDiff = null;
                pendingChanges = 0;

                if (changes && changes.length) {
                    target['notifySubscribers'](changes, arrayChangeEventName);
                }
            }
        }
    }

    function getChanges(previousContents, currentContents) {
        // We try to re-use cached diffs.
        // The scenarios where pendingChanges > 1 are when using rate limiting or deferred updates,
        // which without this check would not be compatible with arrayChange notifications. Normally,
        // notifications are issued immediately so we wouldn't be queueing up more than one.
        if (!cachedDiff || pendingChanges > 1) {
            cachedDiff = ko.utils.compareArrays(previousContents, currentContents, target.compareArrayOptions);
        }

        return cachedDiff;
    }

    target.cacheDiffForKnownOperation = (rawArray, operationName, args) => {
        // Only run if we're currently tracking changes for this observable array
        // and there aren't any pending deferred notifications.
        if (!trackingChanges || pendingChanges) {
            return;
        }
        var diff = [],
            arrayLength = rawArray.length,
            argsLength = args.length,
            offset = 0;

        function pushDiff(status, value, index) {
            return diff[diff.length] = { 'status': status, 'value': value, 'index': index };
        }
        switch (operationName) {
            case 'push':
                offset = arrayLength;
            case 'unshift':
                for (var index = 0; index < argsLength; index++) {
                    pushDiff('added', args[index], offset + index);
                }
                break;

            case 'pop':
                offset = arrayLength - 1;
            case 'shift':
                if (arrayLength) {
                    pushDiff('deleted', rawArray[offset], offset);
                }
                break;

            case 'splice':
                // Negative start index means 'from end of array'. After that we clamp to [0...arrayLength].
                // See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/splice
                var startIndex = Math.min(Math.max(0, args[0] < 0 ? arrayLength + args[0] : args[0]), arrayLength),
                    endDeleteIndex = argsLength === 1 ? arrayLength : Math.min(startIndex + (args[1] || 0), arrayLength),
                    endAddIndex = startIndex + argsLength - 2,
                    endIndex = Math.max(endDeleteIndex, endAddIndex),
                    additions = [], deletions = [];
                for (var index = startIndex, argsIndex = 2; index < endIndex; ++index, ++argsIndex) {
                    if (index < endDeleteIndex)
                        deletions.push(pushDiff('deleted', rawArray[index], index));
                    if (index < endAddIndex)
                        additions.push(pushDiff('added', args[argsIndex], index));
                }
                ko.utils.findMovesInArrayComparison(deletions, additions);
                break;

            default:
                return;
        }
        cachedDiff = diff;
    };
};
var computedState = Symbol('_state');

ko.computed = function (evaluatorFunctionOrOptions, evaluatorFunctionTarget, options) {
    if (typeof evaluatorFunctionOrOptions === "object") {
        // Single-parameter syntax - everything is on this "options" param
        options = evaluatorFunctionOrOptions;
    } else {
        // Multi-parameter syntax - construct the options according to the params passed
        options = options || {};
        if (evaluatorFunctionOrOptions) {
            options["read"] = evaluatorFunctionOrOptions;
        }
    }
    if (typeof options["read"] != "function")
        throw Error("Pass a function that returns the value of the ko.computed");

    var writeFunction = options["write"];
    var state = {
        latestValue: undefined,
        isStale: true,
        isDirty: true,
        isBeingEvaluated: false,
        suppressDisposalUntilDisposeWhenReturnsFalse: false,
        isDisposed: false,
        pure: false,
        isSleeping: false,
        readFunction: options["read"],
        evaluatorFunctionTarget: evaluatorFunctionTarget || options["owner"],
        disposeWhenNodeIsRemoved: options["disposeWhenNodeIsRemoved"] || options.disposeWhenNodeIsRemoved || null,
        disposeWhen: options["disposeWhen"] || options.disposeWhen,
        domNodeDisposalCallback: null,
        dependencyTracking: {},
        dependenciesCount: 0,
        evaluationTimeoutInstance: null
    };

    function computedObservable() {
        if (arguments.length > 0) {
            if (typeof writeFunction === "function") {
                // Writing a value
                writeFunction.apply(state.evaluatorFunctionTarget, arguments);
            } else {
                throw new Error("Cannot write a value to a ko.computed unless you specify a 'write' option. If you wish to read the current value, don't pass any parameters.");
            }
            return this; // Permits chained assignments
        } else {
            // Reading the value
            if (!state.isDisposed) {
                ko.dependencyDetection.registerDependency(computedObservable);
            }
            if (state.isDirty || (state.isSleeping && computedObservable.haveDependenciesChanged())) {
                computedObservable.evaluateImmediate();
            }
            return state.latestValue;
        }
    }

    computedObservable[computedState] = state;
    computedObservable.hasWriteFunction = typeof writeFunction === "function";

    // Inherit from 'subscribable'
    if (!ko.utils.canSetPrototype) {
        // 'subscribable' won't be on the prototype chain unless we put it there directly
        ko.utils.extend(computedObservable, ko.subscribable['fn']);
    }
    ko.subscribable['fn'].init(computedObservable);

    // Inherit from 'computed'
    ko.utils.setPrototypeOfOrExtend(computedObservable, computedFn);

    if (options['pure']) {
        state.pure = true;
        state.isSleeping = true;     // Starts off sleeping; will awake on the first subscription
        ko.utils.extend(computedObservable, pureComputedOverrides);
    } else if (options['deferEvaluation']) {
        ko.utils.extend(computedObservable, deferEvaluationOverrides);
    }

    if (DEBUG) {
        // #1731 - Aid debugging by exposing the computed's options
        computedObservable["_options"] = options;
    }

    if (state.disposeWhenNodeIsRemoved) {
        // Since this computed is associated with a DOM node, and we don't want to dispose the computed
        // until the DOM node is *removed* from the document (as opposed to never having been in the document),
        // we'll prevent disposal until "disposeWhen" first returns false.
        state.suppressDisposalUntilDisposeWhenReturnsFalse = true;

        // disposeWhenNodeIsRemoved: true can be used to opt into the "only dispose after first false result"
        // behaviour even if there's no specific node to watch. In that case, clear the option so we don't try
        // to watch for a non-node's disposal. This technique is intended for KO's internal use only and shouldn't
        // be documented or used by application code, as it's likely to change in a future version of KO.
        if (!state.disposeWhenNodeIsRemoved.nodeType) {
            state.disposeWhenNodeIsRemoved = null;
        }
    }

    // Evaluate, unless sleeping or deferEvaluation is true
    if (!state.isSleeping && !options['deferEvaluation']) {
        computedObservable.evaluateImmediate();
    }

    // Attach a DOM node disposal callback so that the computed will be proactively disposed as soon as the node is
    // removed using ko.removeNode. But skip if isActive is false (there will never be any dependencies to dispose).
    if (state.disposeWhenNodeIsRemoved && computedObservable.isActive()) {
        ko.utils.domNodeDisposal.addDisposeCallback(state.disposeWhenNodeIsRemoved, state.domNodeDisposalCallback = function () {
            computedObservable.dispose();
        });
    }

    return computedObservable;
};

// Utility function that disposes a given dependencyTracking entry
function computedDisposeDependencyCallback(id, entryToDispose) {
    if (entryToDispose !== null && entryToDispose.dispose) {
        entryToDispose.dispose();
    }
}

// This function gets called each time a dependency is detected while evaluating a computed.
// It's factored out as a shared function to avoid creating unnecessary function instances during evaluation.
function computedBeginDependencyDetectionCallback(subscribable, id) {
    var computedObservable = this.computedObservable,
        state = computedObservable[computedState];
    if (!state.isDisposed) {
        if (this.disposalCount && this.disposalCandidates[id]) {
            // Don't want to dispose this subscription, as it's still being used
            computedObservable.addDependencyTracking(id, subscribable, this.disposalCandidates[id]);
            this.disposalCandidates[id] = null; // No need to actually delete the property - disposalCandidates is a transient object anyway
            --this.disposalCount;
        } else if (!state.dependencyTracking[id]) {
            // Brand new subscription - add it
            computedObservable.addDependencyTracking(id, subscribable, state.isSleeping ? { _target: subscribable } : computedObservable.subscribeToDependency(subscribable));
        }
        // If the observable we've accessed has a pending notification, ensure we get notified of the actual final value (bypass equality checks)
        if (subscribable._notificationIsPending) {
            subscribable._notifyNextChangeIfValueIsDifferent();
        }
    }
}

var computedFn = {
    "equalityComparer": valuesArePrimitiveAndEqual,
    getDependenciesCount: function () {
        return this[computedState].dependenciesCount;
    },
    getDependencies: function () {
        var dependencyTracking = this[computedState].dependencyTracking, dependentObservables = [];

        ko.utils.objectForEach(dependencyTracking, (id, dependency) =>
            dependentObservables[dependency._order] = dependency._target
        );

        return dependentObservables;
    },
    hasAncestorDependency: function (obs) {
        if (!this[computedState].dependenciesCount) {
            return false;
        }
        var dependencies = this.getDependencies();
        if (ko.utils.arrayIndexOf(dependencies, obs) !== -1) {
            return true;
        }
        return !!ko.utils.arrayFirst(dependencies, dep =>
            dep.hasAncestorDependency && dep.hasAncestorDependency(obs)
        );
    },
    addDependencyTracking: function (id, target, trackingObj) {
        if (this[computedState].pure && target === this) {
            throw Error("A 'pure' computed must not be called recursively");
        }

        this[computedState].dependencyTracking[id] = trackingObj;
        trackingObj._order = this[computedState].dependenciesCount++;
        trackingObj._version = target.getVersion();
    },
    haveDependenciesChanged: function () {
        var id, dependency, dependencyTracking = this[computedState].dependencyTracking;
        for (id in dependencyTracking) {
            if (Object.prototype.hasOwnProperty.call(dependencyTracking, id)) {
                dependency = dependencyTracking[id];
                if ((this._evalDelayed && dependency._target._notificationIsPending) || dependency._target.hasChanged(dependency._version)) {
                    return true;
                }
            }
        }
    },
    markDirty: function () {
        // Process "dirty" events if we can handle delayed notifications
        if (this._evalDelayed && !this[computedState].isBeingEvaluated) {
            this._evalDelayed(false /*isChange*/);
        }
    },
    isActive: function () {
        var state = this[computedState];
        return state.isDirty || state.dependenciesCount > 0;
    },
    respondToChange: function () {
        // Ignore "change" events if we've already scheduled a delayed notification
        if (!this._notificationIsPending) {
            this.evaluatePossiblyAsync();
        } else if (this[computedState].isDirty) {
            this[computedState].isStale = true;
        }
    },
    subscribeToDependency: function (target) {
        return target.subscribe(this.evaluatePossiblyAsync, this);
    },
    evaluatePossiblyAsync: function () {
        var computedObservable = this,
            throttleEvaluationTimeout = computedObservable['throttleEvaluation'];
        if (throttleEvaluationTimeout && throttleEvaluationTimeout >= 0) {
            clearTimeout(this[computedState].evaluationTimeoutInstance);
            this[computedState].evaluationTimeoutInstance = ko.utils.setTimeout(() =>
                computedObservable.evaluateImmediate(true /*notifyChange*/)
            , throttleEvaluationTimeout);
        } else if (computedObservable._evalDelayed) {
            computedObservable._evalDelayed(true /*isChange*/);
        } else {
            computedObservable.evaluateImmediate(true /*notifyChange*/);
        }
    },
    evaluateImmediate: function (notifyChange) {
        var computedObservable = this,
            state = computedObservable[computedState],
            disposeWhen = state.disposeWhen,
            changed = false;

        if (state.isBeingEvaluated) {
            // If the evaluation of a ko.computed causes side effects, it's possible that it will trigger its own re-evaluation.
            // This is not desirable (it's hard for a developer to realise a chain of dependencies might cause this, and they almost
            // certainly didn't intend infinite re-evaluations). So, for predictability, we simply prevent ko.computeds from causing
            // their own re-evaluation. Further discussion at https://github.com/SteveSanderson/knockout/pull/387
            return;
        }

        // Do not evaluate (and possibly capture new dependencies) if disposed
        if (state.isDisposed) {
            return;
        }

        if (state.disposeWhenNodeIsRemoved && !ko.utils.domNodeIsAttachedToDocument(state.disposeWhenNodeIsRemoved) || disposeWhen && disposeWhen()) {
            // See comment above about suppressDisposalUntilDisposeWhenReturnsFalse
            if (!state.suppressDisposalUntilDisposeWhenReturnsFalse) {
                computedObservable.dispose();
                return;
            }
        } else {
            // It just did return false, so we can stop suppressing now
            state.suppressDisposalUntilDisposeWhenReturnsFalse = false;
        }

        state.isBeingEvaluated = true;
        try {
            changed = this.evaluateImmediate_CallReadWithDependencyDetection(notifyChange);
        } finally {
            state.isBeingEvaluated = false;
        }

        return changed;
    },
    evaluateImmediate_CallReadWithDependencyDetection: function (notifyChange) {
        // This function is really just part of the evaluateImmediate logic. You would never call it from anywhere else.
        // Factoring it out into a separate function means it can be independent of the try/catch block in evaluateImmediate,
        // which contributes to saving about 40% off the CPU overhead of computed evaluation (on V8 at least).

        var computedObservable = this,
            state = computedObservable[computedState],
            changed = false;

        // Initially, we assume that none of the subscriptions are still being used (i.e., all are candidates for disposal).
        // Then, during evaluation, we cross off any that are in fact still being used.
        var isInitial = state.pure ? undefined : !state.dependenciesCount,   // If we're evaluating when there are no previous dependencies, it must be the first time
            dependencyDetectionContext = {
                computedObservable: computedObservable,
                disposalCandidates: state.dependencyTracking,
                disposalCount: state.dependenciesCount
            };

        ko.dependencyDetection.begin({
            callbackTarget: dependencyDetectionContext,
            callback: computedBeginDependencyDetectionCallback,
            computed: computedObservable,
            isInitial: isInitial
        });

        state.dependencyTracking = {};
        state.dependenciesCount = 0;

        var newValue = this.evaluateImmediate_CallReadThenEndDependencyDetection(state, dependencyDetectionContext);

        if (!state.dependenciesCount) {
            computedObservable.dispose();
            changed = true; // When evaluation causes a disposal, make sure all dependent computeds get notified so they'll see the new state
        } else {
            changed = computedObservable.isDifferent(state.latestValue, newValue);
        }

        if (changed) {
            if (!state.isSleeping) {
                computedObservable["notifySubscribers"](state.latestValue, "beforeChange");
            } else {
                computedObservable.updateVersion();
            }

            state.latestValue = newValue;
            if (DEBUG) computedObservable._latestValue = newValue;

            computedObservable["notifySubscribers"](state.latestValue, "spectate");

            if (!state.isSleeping && notifyChange) {
                computedObservable["notifySubscribers"](state.latestValue);
            }
            if (computedObservable._recordUpdate) {
                computedObservable._recordUpdate();
            }
        }

        if (isInitial) {
            computedObservable["notifySubscribers"](state.latestValue, "awake");
        }

        return changed;
    },
    evaluateImmediate_CallReadThenEndDependencyDetection: (state, dependencyDetectionContext) => {
        // This function is really part of the evaluateImmediate_CallReadWithDependencyDetection logic.
        // You'd never call it from anywhere else. Factoring it out means that evaluateImmediate_CallReadWithDependencyDetection
        // can be independent of try/finally blocks, which contributes to saving about 40% off the CPU
        // overhead of computed evaluation (on V8 at least).

        try {
            var readFunction = state.readFunction;
            return state.evaluatorFunctionTarget ? readFunction.call(state.evaluatorFunctionTarget) : readFunction();
        } finally {
            ko.dependencyDetection.end();

            // For each subscription no longer being used, remove it from the active subscriptions list and dispose it
            if (dependencyDetectionContext.disposalCount && !state.isSleeping) {
                ko.utils.objectForEach(dependencyDetectionContext.disposalCandidates, computedDisposeDependencyCallback);
            }

            state.isStale = state.isDirty = false;
        }
    },
    peek: function (evaluate) {
        // By default, peek won't re-evaluate, except while the computed is sleeping or to get the initial value when "deferEvaluation" is set.
        // Pass in true to evaluate if needed.
        var state = this[computedState];
        if ((state.isDirty && (evaluate || !state.dependenciesCount)) || (state.isSleeping && this.haveDependenciesChanged())) {
            this.evaluateImmediate();
        }
        return state.latestValue;
    },
    limit: function (limitFunction) {
        // Override the limit function with one that delays evaluation as well
        ko.subscribable['fn'].limit.call(this, limitFunction);
        this._evalIfChanged = function () {
            if (!this[computedState].isSleeping) {
                if (this[computedState].isStale) {
                    this.evaluateImmediate();
                } else {
                    this[computedState].isDirty = false;
                }
            }
            return this[computedState].latestValue;
        };
        this._evalDelayed = function (isChange) {
            this._limitBeforeChange(this[computedState].latestValue);

            // Mark as dirty
            this[computedState].isDirty = true;
            if (isChange) {
                this[computedState].isStale = true;
            }

            // Pass the observable to the "limit" code, which will evaluate it when
            // it's time to do the notification.
            this._limitChange(this, !isChange /* isDirty */);
        };
    },
    dispose: function () {
        var state = this[computedState];
        if (!state.isSleeping && state.dependencyTracking) {
            ko.utils.objectForEach(state.dependencyTracking, (id, dependency) =>
                dependency.dispose && dependency.dispose()
            );
        }
        if (state.disposeWhenNodeIsRemoved && state.domNodeDisposalCallback) {
            ko.utils.domNodeDisposal.removeDisposeCallback(state.disposeWhenNodeIsRemoved, state.domNodeDisposalCallback);
        }
        state.dependencyTracking = undefined;
        state.dependenciesCount = 0;
        state.isDisposed = true;
        state.isStale = false;
        state.isDirty = false;
        state.isSleeping = false;
        state.disposeWhenNodeIsRemoved = undefined;
        state.disposeWhen = undefined;
        state.readFunction = undefined;
        if (!this.hasWriteFunction) {
            state.evaluatorFunctionTarget = undefined;
        }
    }
};

var pureComputedOverrides = {
    beforeSubscriptionAdd: function (event) {
        // If asleep, wake up the computed by subscribing to any dependencies.
        var computedObservable = this,
            state = computedObservable[computedState];
        if (!state.isDisposed && state.isSleeping && event == 'change') {
            state.isSleeping = false;
            if (state.isStale || computedObservable.haveDependenciesChanged()) {
                state.dependencyTracking = null;
                state.dependenciesCount = 0;
                if (computedObservable.evaluateImmediate()) {
                    computedObservable.updateVersion();
                }
            } else {
                // First put the dependencies in order
                var dependenciesOrder = [];
                ko.utils.objectForEach(state.dependencyTracking, (id, dependency) =>
                    dependenciesOrder[dependency._order] = id
                );
                // Next, subscribe to each one
                ko.utils.arrayForEach(dependenciesOrder, (id, order) => {
                    var dependency = state.dependencyTracking[id],
                        subscription = computedObservable.subscribeToDependency(dependency._target);
                    subscription._order = order;
                    subscription._version = dependency._version;
                    state.dependencyTracking[id] = subscription;
                });
                // Waking dependencies may have triggered effects
                if (computedObservable.haveDependenciesChanged()) {
                    if (computedObservable.evaluateImmediate()) {
                        computedObservable.updateVersion();
                    }
                }
            }

            if (!state.isDisposed) {     // test since evaluating could trigger disposal
                computedObservable["notifySubscribers"](state.latestValue, "awake");
            }
        }
    },
    afterSubscriptionRemove: function (event) {
        var state = this[computedState];
        if (!state.isDisposed && event == 'change' && !this.hasSubscriptionsForEvent('change')) {
            ko.utils.objectForEach(state.dependencyTracking, (id, dependency) => {
                if (dependency.dispose) {
                    state.dependencyTracking[id] = {
                        _target: dependency._target,
                        _order: dependency._order,
                        _version: dependency._version
                    };
                    dependency.dispose();
                }
            });
            state.isSleeping = true;
            this["notifySubscribers"](undefined, "asleep");
        }
    },
    getVersion: function () {
        // Because a pure computed is not automatically updated while it is sleeping, we can't
        // simply return the version number. Instead, we check if any of the dependencies have
        // changed and conditionally re-evaluate the computed observable.
        var state = this[computedState];
        if (state.isSleeping && (state.isStale || this.haveDependenciesChanged())) {
            this.evaluateImmediate();
        }
        return ko.subscribable['fn'].getVersion.call(this);
    }
};

var deferEvaluationOverrides = {
    beforeSubscriptionAdd: function (event) {
        // This will force a computed with deferEvaluation to evaluate when the first subscription is registered.
        if (event == 'change' || event == 'beforeChange') {
            this.peek();
        }
    }
};

// Note that for browsers that don't support proto assignment, the
// inheritance chain is created manually in the ko.computed constructor
if (ko.utils.canSetPrototype) {
    ko.utils.setPrototypeOf(computedFn, ko.subscribable['fn']);
}

// Set the proto values for ko.computed
var protoProp = ko.observable.protoProperty; // == "__ko_proto__"
computedFn[protoProp] = ko.computed;

ko.exportSymbol('computed', ko.computed);
ko.exportSymbol('computed.fn', computedFn);
ko.exportProperty(computedFn, 'dispose', computedFn.dispose);

ko.pureComputed = (evaluatorFunctionOrOptions, evaluatorFunctionTarget) => {
    if (typeof evaluatorFunctionOrOptions === 'function') {
        return ko.computed(evaluatorFunctionOrOptions, evaluatorFunctionTarget, {'pure':true});
    }
    evaluatorFunctionOrOptions = ko.utils.extend({}, evaluatorFunctionOrOptions);   // make a copy of the parameter object
    evaluatorFunctionOrOptions['pure'] = true;
    return ko.computed(evaluatorFunctionOrOptions, evaluatorFunctionTarget);
};
(() => {
    var hasDomDataExpandoProperty = '__ko__hasDomDataOptionValue__';

    // Normally, SELECT elements and their OPTIONs can only take value of type 'string' (because the values
    // are stored on DOM attributes). ko.selectExtensions provides a way for SELECTs/OPTIONs to have values
    // that are arbitrary objects. This is very convenient when implementing things like cascading dropdowns.
    ko.selectExtensions = {
        readValue : element => {
            switch (ko.utils.tagNameLower(element)) {
                case 'option':
                    if (element[hasDomDataExpandoProperty] === true)
                        return ko.utils.domData.get(element, ko.bindingHandlers.options.optionValueDomDataKey);
                    return element.value;
                case 'select':
                    return element.selectedIndex >= 0 ? ko.selectExtensions.readValue(element.options[element.selectedIndex]) : undefined;
                default:
                    return element.value;
            }
        },

        writeValue: (element, value, allowUnset) => {
            switch (ko.utils.tagNameLower(element)) {
                case 'option':
                    if (typeof value === "string") {
                        ko.utils.domData.set(element, ko.bindingHandlers.options.optionValueDomDataKey, undefined);
                        delete element[hasDomDataExpandoProperty];
                        element.value = value;
                    }
                    else {
                        // Store arbitrary object using DomData
                        ko.utils.domData.set(element, ko.bindingHandlers.options.optionValueDomDataKey, value);
                        element[hasDomDataExpandoProperty] = true;

                        // Special treatment of numbers is just for backward compatibility. KO 1.2.1 wrote numerical values to element.value.
                        element.value = typeof value === "number" ? value : "";
                    }
                    break;
                case 'select':
                    if (value === "" || value === null)       // A blank string or null value will select the caption
                        value = undefined;
                    var selection = -1;
                    for (var i = 0, n = element.options.length, optionValue; i < n; ++i) {
                        optionValue = ko.selectExtensions.readValue(element.options[i]);
                        // Include special check to handle selecting a caption with a blank string value
                        if (optionValue == value || (optionValue === "" && value === undefined)) {
                            selection = i;
                            break;
                        }
                    }
                    if (allowUnset || selection >= 0 || (value === undefined && element.size > 1)) {
                        element.selectedIndex = selection;
                    }
                    break;
                default:
                    if ((value === null) || (value === undefined))
                        value = "";
                    element.value = value;
                    break;
            }
        }
    };
})();
ko.expressionRewriting = (() => {
    var javaScriptReservedWords = ["true", "false", "null", "undefined"];

    // Matches something that can be assigned to--either an isolated identifier or something ending with a property accessor
    // This is designed to be simple and avoid false negatives, but could produce false positives (e.g., a+b.c).
    // This also will not properly handle nested brackets (e.g., obj1[obj2['prop']]; see #911).
    var javaScriptAssignmentTarget = /^(?:[$_a-z][$\w]*|(.+)(\.\s*[$_a-z][$\w]*|\[.+\]))$/i;

    function getWriteableValue(expression) {
        if (ko.utils.arrayIndexOf(javaScriptReservedWords, expression) >= 0)
            return false;
        var match = expression.match(javaScriptAssignmentTarget);
        return match === null ? false : match[1] ? ('Object(' + match[1] + ')' + match[2]) : expression;
    }

    // The following regular expressions will be used to split an object-literal string into tokens

    var specials = ',"\'`{}()/:[\\]',    // These characters have special meaning to the parser and must not appear in the middle of a token, except as part of a string.
        // Create the actual regular expression by or-ing the following regex strings. The order is important.
        bindingToken = RegExp([
            // These match strings, either with double quotes, single quotes, or backticks
            '"(?:\\\\.|[^"])*"',
            "'(?:\\\\.|[^'])*'",
            "`(?:\\\\.|[^`])*`",
            // Match C style comments
            "/\\*(?:[^*]|\\*+[^*/])*\\*+/",
            // Match C++ style comments
            "//.*\n",
            // Match a regular expression (text enclosed by slashes), but will also match sets of divisions
            // as a regular expression (this is handled by the parsing loop below).
            '/(?:\\\\.|[^/])+/w*',
            // Match text (at least two characters) that does not contain any of the above special characters,
            // although some of the special characters are allowed to start it (all but the colon and comma).
            // The text can contain spaces, but leading or trailing spaces are skipped.
            '[^\\s:,/][^' + specials + ']*[^\\s' + specials + ']',
            // Match any non-space character not matched already. This will match colons and commas, since they're
            // not matched by "everyThingElse", but will also match any other single character that wasn't already
            // matched (for example: in "a: 1, b: 2", each of the non-space characters will be matched by oneNotSpace).
            '[^\\s]'
        ].join('|'), 'g'),

        // Match end of previous token to determine whether a slash is a division or regex.
        divisionLookBehind = /[\])"'A-Za-z0-9_$]+$/,
        keywordRegexLookBehind = {'in':1,'return':1,'typeof':1};

    function parseObjectLiteral(objectLiteralString) {
        // Trim leading and trailing spaces from the string
        var str = ko.utils.stringTrim(objectLiteralString);

        // Trim braces '{' surrounding the whole object literal
        if (str.charCodeAt(0) === 123) str = str.slice(1, -1);

        // Add a newline to correctly match a C++ style comment at the end of the string and
        // add a comma so that we don't need a separate code block to deal with the last item
        str += "\n,";

        // Split into tokens
        var result = [], toks = str.match(bindingToken), key, values = [], depth = 0;

        if (toks.length > 1) {
            for (var i = 0, tok; tok = toks[i]; ++i) {
                var c = tok.charCodeAt(0);
                // A comma signals the end of a key/value pair if depth is zero
                if (c === 44) { // ","
                    if (depth <= 0) {
                        result.push((key && values.length) ? {key: key, value: values.join('')} : {'unknown': key || values.join('')});
                        key = depth = 0;
                        values = [];
                        continue;
                    }
                // Simply skip the colon that separates the name and value
                } else if (c === 58) { // ":"
                    if (!depth && !key && values.length === 1) {
                        key = values.pop();
                        continue;
                    }
                // Comments: skip them
                } else if (c === 47 && tok.length > 1 && (tok.charCodeAt(1) === 47 || tok.charCodeAt(1) === 42)) {  // "//" or "/*"
                    continue;
                // A set of slashes is initially matched as a regular expression, but could be division
                } else if (c === 47 && i && tok.length > 1) {  // "/"
                    // Look at the end of the previous token to determine if the slash is actually division
                    var match = toks[i-1].match(divisionLookBehind);
                    if (match && !keywordRegexLookBehind[match[0]]) {
                        // The slash is actually a division punctuator; re-parse the remainder of the string (not including the slash)
                        str = str.substr(str.indexOf(tok) + 1);
                        toks = str.match(bindingToken);
                        i = -1;
                        // Continue with just the slash
                        tok = '/';
                    }
                // Increment depth for parentheses, braces, and brackets so that interior commas are ignored
                } else if (c === 40 || c === 123 || c === 91) { // '(', '{', '['
                    ++depth;
                } else if (c === 41 || c === 125 || c === 93) { // ')', '}', ']'
                    --depth;
                // The key will be the first token; if it's a string, trim the quotes
                } else if (!key && !values.length && (c === 34 || c === 39)) { // '"', "'"
                    tok = tok.slice(1, -1);
                }
                values.push(tok);
            }
            if (depth > 0) {
                throw Error("Unbalanced parentheses, braces, or brackets");
            }
        }
        return result;
    }

    // Two-way bindings include a write function that allow the handler to update the value even if it's not an observable.
    var twoWayBindings = {};

    function preProcessBindings(bindingsStringOrKeyValueArray, bindingOptions) {
        bindingOptions = bindingOptions || {};

        function processKeyValue(key, val) {
            var writableVal;
            function callPreprocessHook(obj) {
                return (obj && obj['preprocess']) ? (val = obj['preprocess'](val, key, processKeyValue)) : true;
            }
            if (!bindingParams) {
                if (!callPreprocessHook(ko['getBindingHandler'](key)))
                    return;

                if (twoWayBindings[key] && (writableVal = getWriteableValue(val))) {
                    // For two-way bindings, provide a write method in case the value
                    // isn't a writable observable.
                    var writeKey = typeof twoWayBindings[key] == 'string' ? twoWayBindings[key] : key;
                    propertyAccessorResultStrings.push("'" + writeKey + "':function(_z){" + writableVal + "=_z}");
                }
            }
            // Values are wrapped in a function so that each value can be accessed independently
            if (makeValueAccessors) {
                val = 'function(){return ' + val + ' }';
            }
            resultStrings.push("'" + key + "':" + val);
        }

        var resultStrings = [],
            propertyAccessorResultStrings = [],
            makeValueAccessors = bindingOptions['valueAccessors'],
            bindingParams = bindingOptions['bindingParams'],
            keyValueArray = typeof bindingsStringOrKeyValueArray === "string" ?
                parseObjectLiteral(bindingsStringOrKeyValueArray) : bindingsStringOrKeyValueArray;

        ko.utils.arrayForEach(keyValueArray, keyValue =>
            processKeyValue(keyValue.key || keyValue['unknown'], keyValue.value)
        );

        if (propertyAccessorResultStrings.length)
            processKeyValue('_ko_property_writers', "{" + propertyAccessorResultStrings.join(",") + " }");

        return resultStrings.join(",");
    }

    return {
        bindingRewriteValidators: [],

        twoWayBindings: twoWayBindings,

        parseObjectLiteral: parseObjectLiteral,

        preProcessBindings: preProcessBindings,

        keyValueArrayContainsKey: (keyValueArray, key) => {
            for (var i = 0; i < keyValueArray.length; i++)
                if (keyValueArray[i]['key'] == key)
                    return true;
            return false;
        },

        // Internal, private KO utility for updating model properties from within bindings
        // property:            If the property being updated is (or might be) an observable, pass it here
        //                      If it turns out to be a writable observable, it will be written to directly
        // allBindings:         An object with a get method to retrieve bindings in the current execution context.
        //                      This will be searched for a '_ko_property_writers' property in case you're writing to a non-observable
        // key:                 The key identifying the property to be written. Example: for { hasFocus: myValue }, write to 'myValue' by specifying the key 'hasFocus'
        // value:               The value to be written
        // checkIfDifferent:    If true, and if the property being written is a writable observable, the value will only be written if
        //                      it is !== existing value on that writable observable
        writeValueToProperty: (property, allBindings, key, value, checkIfDifferent) => {
            if (!property || !ko.isObservable(property)) {
                var propWriters = allBindings.get('_ko_property_writers');
                if (propWriters && propWriters[key])
                    propWriters[key](value);
            } else if (ko.isWriteableObservable(property) && (!checkIfDifferent || property.peek() !== value)) {
                property(value);
            }
        }
    };
})();
(() => {
    // "Virtual elements" is an abstraction on top of the usual DOM API which understands the notion that comment nodes
    // may be used to represent hierarchy (in addition to the DOM's natural hierarchy).
    // If you call the DOM-manipulating functions on ko.virtualElements, you will be able to read and write the state
    // of that virtual hierarchy
    //
    // The point of all this is to support containerless templates (e.g., <!-- ko foreach:someCollection -->blah<!-- /ko -->)
    // without having to scatter special cases all over the binding and templating code.

    var startCommentRegex = /^\s*ko(?:\s+([\s\S]+))?\s*$/;
    var endCommentRegex =   /^\s*\/ko\s*$/;

    function isStartComment(node) {
        return (node.nodeType == 8) && startCommentRegex.test(node.nodeValue);
    }

    function isEndComment(node) {
        return (node.nodeType == 8) && endCommentRegex.test(node.nodeValue);
    }

    function isUnmatchedEndComment(node) {
        return isEndComment(node) && !(ko.utils.domData.get(node, matchedEndCommentDataKey));
    }

    var matchedEndCommentDataKey = "__ko_matchedEndComment__"

    function getVirtualChildren(startComment, allowUnbalanced) {
        var currentNode = startComment;
        var depth = 1;
        var children = [];
        while (currentNode = currentNode.nextSibling) {
            if (isEndComment(currentNode)) {
                ko.utils.domData.set(currentNode, matchedEndCommentDataKey, true);
                depth--;
                if (depth === 0)
                    return children;
            }

            children.push(currentNode);

            if (isStartComment(currentNode))
                depth++;
        }
        if (!allowUnbalanced)
            throw new Error("Cannot find closing comment tag to match: " + startComment.nodeValue);
        return null;
    }

    function getMatchingEndComment(startComment, allowUnbalanced) {
        var allVirtualChildren = getVirtualChildren(startComment, allowUnbalanced);
        if (allVirtualChildren) {
            if (allVirtualChildren.length > 0)
                return allVirtualChildren[allVirtualChildren.length - 1].nextSibling;
            return startComment.nextSibling;
        }
        return null; // Must have no matching end comment, and allowUnbalanced is true
    }

    ko.virtualElements = {
        allowedBindings: {},

        childNodes: node => isStartComment(node) ? getVirtualChildren(node) : node.childNodes,

        emptyNode: node => {
            if (!isStartComment(node))
                ko.utils.emptyDomNode(node);
            else {
                var virtualChildren = ko.virtualElements.childNodes(node);
                for (var i = 0, j = virtualChildren.length; i < j; i++)
                    ko.removeNode(virtualChildren[i]);
            }
        },

        setDomNodeChildren: (node, childNodes) => {
            if (!isStartComment(node))
                ko.utils.setDomNodeChildren(node, childNodes);
            else {
                ko.virtualElements.emptyNode(node);
                var endCommentNode = node.nextSibling; // Must be the next sibling, as we just emptied the children
                for (var i = 0, j = childNodes.length; i < j; i++)
                    endCommentNode.parentNode.insertBefore(childNodes[i], endCommentNode);
            }
        },

        prepend: (containerNode, nodeToPrepend) => {
            var insertBeforeNode;

            if (isStartComment(containerNode)) {
                // Start comments must always have a parent and at least one following sibling (the end comment)
                insertBeforeNode = containerNode.nextSibling;
                containerNode = containerNode.parentNode;
            } else {
                insertBeforeNode = containerNode.firstChild;
            }

            containerNode.insertBefore(nodeToPrepend, insertBeforeNode);
        },

        insertAfter: (containerNode, nodeToInsert, insertAfterNode) => {
            if (!insertAfterNode) {
                ko.virtualElements.prepend(containerNode, nodeToInsert);
            } else {
                // Children of start comments must always have a parent and at least one following sibling (the end comment)
                var insertBeforeNode = insertAfterNode.nextSibling;

                if (isStartComment(containerNode)) {
                    containerNode = containerNode.parentNode;
                }

                containerNode.insertBefore(nodeToInsert, insertBeforeNode);
            }
        },

        firstChild: node => {
            if (!isStartComment(node)) {
                if (node.firstChild && isEndComment(node.firstChild)) {
                    throw new Error("Found invalid end comment, as the first child of " + node);
                }
                return node.firstChild;
            }
            return (!node.nextSibling || isEndComment(node.nextSibling)) ? null : node.nextSibling;
        },

        nextSibling: node => {
            if (isStartComment(node)) {
                node = getMatchingEndComment(node);
            }

            if (node.nextSibling && isEndComment(node.nextSibling)) {
                if (isUnmatchedEndComment(node.nextSibling)) {
                    throw Error("Found end comment without a matching opening comment, as child of " + node);
                }
                return null;
            }
            return node.nextSibling;
        },

        hasBindingValue: isStartComment,

        virtualNodeBindingValue: node => {
            var regexMatch = (node.nodeValue).match(startCommentRegex);
            return regexMatch ? regexMatch[1] : null;
        }
    };
})();
(function() {
    var defaultBindingAttributeName = "data-bind";

    ko.bindingProvider = function() {
        this.bindingCache = {};
    };

    ko.utils.extend(ko.bindingProvider.prototype, {
        'nodeHasBindings': node => {
            switch (node.nodeType) {
                case 1: // Element
                    return node.getAttribute(defaultBindingAttributeName) != null
                        || ko.components['getComponentNameForNode'](node);
                case 8: // Comment node
                    return ko.virtualElements.hasBindingValue(node);
                default: return false;
            }
        },

        'getBindings': function(node, bindingContext) {
            var bindingsString = this['getBindingsString'](node, bindingContext),
                parsedBindings = bindingsString ? this['parseBindingsString'](bindingsString, bindingContext, node) : null;
            return ko.components.addBindingsForCustomElement(parsedBindings, node, bindingContext, /* valueAccessors */ false);
        },

        'getBindingAccessors': function(node, bindingContext) {
            var bindingsString = this['getBindingsString'](node, bindingContext),
                parsedBindings = bindingsString ? this['parseBindingsString'](bindingsString, bindingContext, node, { 'valueAccessors': true }) : null;
            return ko.components.addBindingsForCustomElement(parsedBindings, node, bindingContext, /* valueAccessors */ true);
        },

        // The following function is only used internally by this default provider.
        // It's not part of the interface definition for a general binding provider.
        'getBindingsString': (node, bindingContext) => {
            switch (node.nodeType) {
                case 1: return node.getAttribute(defaultBindingAttributeName);   // Element
                case 8: return ko.virtualElements.virtualNodeBindingValue(node); // Comment node
            }
            return null;
        },

        // The following function is only used internally by this default provider.
        // It's not part of the interface definition for a general binding provider.
        'parseBindingsString': function(bindingsString, bindingContext, node, options) {
            try {
                var bindingFunction = createBindingsStringEvaluatorViaCache(bindingsString, this.bindingCache, options);
                return bindingFunction(bindingContext, node);
            } catch (ex) {
                ex.message = "Unable to parse bindings.\nBindings value: " + bindingsString + "\nMessage: " + ex.message;
                throw ex;
            }
        }
    });

    ko.bindingProvider['instance'] = new ko.bindingProvider();

    function createBindingsStringEvaluatorViaCache(bindingsString, cache, options) {
        var cacheKey = bindingsString + (options && options['valueAccessors'] || '');
        return cache[cacheKey]
            || (cache[cacheKey] = createBindingsStringEvaluator(bindingsString, options));
    }

    function createBindingsStringEvaluator(bindingsString, options) {
        // Build the source for a function that evaluates "expression"
        // For each scope variable, add an extra level of "with" nesting
        // Example result: with(sc1) { with(sc0) { return (expression) } }
        var rewrittenBindings = ko.expressionRewriting.preProcessBindings(bindingsString, options),
            functionBody = "with($context){with($data||{}){return{" + rewrittenBindings + "}}}";
        return new Function("$context", "$element", functionBody);
    }
})();
(() => {
    // Hide or don't minify context properties, see https://github.com/knockout/knockout/issues/2294
    var contextSubscribable = Symbol('_subscribable');
    var contextAncestorBindingInfo = Symbol('_ancestorBindingInfo');
    var contextDataDependency = Symbol('_dataDependency');

    ko.bindingHandlers = {};

    // The following element types will not be recursed into during binding.
    var bindingDoesNotRecurseIntoElementTypes = {
        // Don't want bindings that operate on text nodes to mutate <script> and <textarea> contents,
        // because it's unexpected and a potential XSS issue.
        // Also bindings should not operate on <template> elements since this breaks in Internet Explorer
        // and because such elements' contents are always intended to be bound in a different context
        // from where they appear in the document.
        'script': true,
        'textarea': true,
        'template': true
    };

    // Use an overridable method for retrieving binding handlers so that plugins may support dynamically created handlers
    ko['getBindingHandler'] = bindingKey => ko.bindingHandlers[bindingKey];

    var inheritParentVm = {};

    // The ko.bindingContext constructor is only called directly to create the root context. For child
    // contexts, use bindingContext.createChildContext or bindingContext.extend.
    ko.bindingContext = function(dataItemOrAccessor, parentContext, dataItemAlias, extendCallback, options) {

        // The binding context object includes static properties for the current, parent, and root view models.
        // If a view model is actually stored in an observable, the corresponding binding context object, and
        // any child contexts, must be updated when the view model is changed.
        function updateContext() {
            // Most of the time, the context will directly get a view model object, but if a function is given,
            // we call the function to retrieve the view model. If the function accesses any observables or returns
            // an observable, the dependency is tracked, and those observables can later cause the binding
            // context to be updated.
            var dataItemOrObservable = isFunc ? realDataItemOrAccessor() : realDataItemOrAccessor,
                dataItem = ko.utils.unwrapObservable(dataItemOrObservable);

            if (parentContext) {
                // Copy $root and any custom properties from the parent context
                ko.utils.extend(self, parentContext);

                // Copy Symbol properties
                if (contextAncestorBindingInfo in parentContext) {
                    self[contextAncestorBindingInfo] = parentContext[contextAncestorBindingInfo];
                }
            } else {
                self['$parents'] = [];
                self['$root'] = dataItem;

                // Export 'ko' in the binding context so it will be available in bindings and templates
                // even if 'ko' isn't exported as a global, such as when using an AMD loader.
                // See https://github.com/SteveSanderson/knockout/issues/490
                self['ko'] = ko;
            }

            self[contextSubscribable] = subscribable;

            if (shouldInheritData) {
                dataItem = self['$data'];
            } else {
                self['$rawData'] = dataItemOrObservable;
                self['$data'] = dataItem;
            }

            if (dataItemAlias)
                self[dataItemAlias] = dataItem;

            // The extendCallback function is provided when creating a child context or extending a context.
            // It handles the specific actions needed to finish setting up the binding context. Actions in this
            // function could also add dependencies to this binding context.
            if (extendCallback)
                extendCallback(self, parentContext, dataItem);

            // When a "parent" context is given and we don't already have a dependency on its context, register a dependency on it.
            // Thus whenever the parent context is updated, this context will also be updated.
            if (parentContext && parentContext[contextSubscribable] && !ko.computedContext.computed().hasAncestorDependency(parentContext[contextSubscribable])) {
                parentContext[contextSubscribable]();
            }

            if (dataDependency) {
                self[contextDataDependency] = dataDependency;
            }

            return self['$data'];
        }

        var self = this,
            shouldInheritData = dataItemOrAccessor === inheritParentVm,
            realDataItemOrAccessor = shouldInheritData ? undefined : dataItemOrAccessor,
            isFunc = typeof(realDataItemOrAccessor) == "function" && !ko.isObservable(realDataItemOrAccessor),
            subscribable,
            dataDependency = options && options['dataDependency'];

        if (options && options['exportDependencies']) {
            // The "exportDependencies" option means that the calling code will track any dependencies and re-create
            // the binding context when they change.
            updateContext();
        } else {
            subscribable = ko.pureComputed(updateContext);
            subscribable.peek();

            // At this point, the binding context has been initialized, and the "subscribable" computed observable is
            // subscribed to any observables that were accessed in the process. If there is nothing to track, the
            // computed will be inactive, and we can safely throw it away. If it's active, the computed is stored in
            // the context object.
            if (subscribable.isActive()) {
                // Always notify because even if the model ($data) hasn't changed, other context properties might have changed
                subscribable['equalityComparer'] = null;
            } else {
                self[contextSubscribable] = undefined;
            }
        }
    }

    // Extend the binding context hierarchy with a new view model object. If the parent context is watching
    // any observables, the new child context will automatically get a dependency on the parent context.
    // But this does not mean that the $data value of the child context will also get updated. If the child
    // view model also depends on the parent view model, you must provide a function that returns the correct
    // view model on each update.
    ko.bindingContext.prototype['createChildContext'] = function (dataItemOrAccessor, dataItemAlias, extendCallback, options) {
        if (!options && dataItemAlias && typeof dataItemAlias == "object") {
            options = dataItemAlias;
            dataItemAlias = options['as'];
            extendCallback = options['extend'];
        }

        if (dataItemAlias && options && options['noChildContext']) {
            var isFunc = typeof(dataItemOrAccessor) == "function" && !ko.isObservable(dataItemOrAccessor);
            return new ko.bindingContext(inheritParentVm, this, null, self => {
                if (extendCallback)
                    extendCallback(self);
                self[dataItemAlias] = isFunc ? dataItemOrAccessor() : dataItemOrAccessor;
            }, options);
        }

        return new ko.bindingContext(dataItemOrAccessor, this, dataItemAlias, (self, parentContext) => {
            // Extend the context hierarchy by setting the appropriate pointers
            self['$parentContext'] = parentContext;
            self['$parent'] = parentContext['$data'];
            self['$parents'] = (parentContext['$parents'] || []).slice(0);
            self['$parents'].unshift(self['$parent']);
            if (extendCallback)
                extendCallback(self);
        }, options);
    };

    // Extend the binding context with new custom properties. This doesn't change the context hierarchy.
    // Similarly to "child" contexts, provide a function here to make sure that the correct values are set
    // when an observable view model is updated.
    ko.bindingContext.prototype['extend'] = function(properties, options) {
        return new ko.bindingContext(inheritParentVm, this, null, self =>
            ko.utils.extend(self, typeof(properties) == "function" ? properties(self) : properties)
        , options);
    };

    var boundElementDomDataKey = ko.utils.domData.nextKey();

    function asyncContextDispose(node) {
        var bindingInfo = ko.utils.domData.get(node, boundElementDomDataKey),
            asyncContext = bindingInfo && bindingInfo.asyncContext;
        if (asyncContext) {
            bindingInfo.asyncContext = null;
            asyncContext.notifyAncestor();
        }
    }
    function AsyncCompleteContext(node, bindingInfo, ancestorBindingInfo) {
        this.node = node;
        this.bindingInfo = bindingInfo;
        this.asyncDescendants = [];
        this.childrenComplete = false;

        if (!bindingInfo.asyncContext) {
            ko.utils.domNodeDisposal.addDisposeCallback(node, asyncContextDispose);
        }

        if (ancestorBindingInfo && ancestorBindingInfo.asyncContext) {
            ancestorBindingInfo.asyncContext.asyncDescendants.push(node);
            this.ancestorBindingInfo = ancestorBindingInfo;
        }
    }
    AsyncCompleteContext.prototype.notifyAncestor = function () {
        if (this.ancestorBindingInfo && this.ancestorBindingInfo.asyncContext) {
            this.ancestorBindingInfo.asyncContext.descendantComplete(this.node);
        }
    };
    AsyncCompleteContext.prototype.descendantComplete = function (node) {
        ko.utils.arrayRemoveItem(this.asyncDescendants, node);
        if (!this.asyncDescendants.length && this.childrenComplete) {
            this.completeChildren();
        }
    };
    AsyncCompleteContext.prototype.completeChildren = function () {
        this.childrenComplete = true;
        if (this.bindingInfo.asyncContext && !this.asyncDescendants.length) {
            this.bindingInfo.asyncContext = null;
            ko.utils.domNodeDisposal.removeDisposeCallback(this.node, asyncContextDispose);
            ko.bindingEvent.notify(this.node, ko.bindingEvent.descendantsComplete);
            this.notifyAncestor();
        }
    };

    ko.bindingEvent = {
        childrenComplete: "childrenComplete",
        descendantsComplete : "descendantsComplete",

        subscribe: (node, event, callback, context, options) => {
            var bindingInfo = ko.utils.domData.getOrSet(node, boundElementDomDataKey, {});
            if (!bindingInfo.eventSubscribable) {
                bindingInfo.eventSubscribable = new ko.subscribable;
            }
            if (options && options['notifyImmediately'] && bindingInfo.notifiedEvents[event]) {
                ko.dependencyDetection.ignore(callback, context, [node]);
            }
            return bindingInfo.eventSubscribable.subscribe(callback, context, event);
        },

        notify: (node, event) => {
            var bindingInfo = ko.utils.domData.get(node, boundElementDomDataKey);
            if (bindingInfo) {
                bindingInfo.notifiedEvents[event] = true;
                if (bindingInfo.eventSubscribable) {
                    bindingInfo.eventSubscribable['notifySubscribers'](node, event);
                }
                if (event == ko.bindingEvent.childrenComplete) {
                    if (bindingInfo.asyncContext) {
                        bindingInfo.asyncContext.completeChildren();
                    } else if (bindingInfo.asyncContext === undefined && bindingInfo.eventSubscribable && bindingInfo.eventSubscribable.hasSubscriptionsForEvent(ko.bindingEvent.descendantsComplete)) {
                        // It's currently an error to register a descendantsComplete handler for a node that was never registered as completing asynchronously.
                        // That's because without the asyncContext, we don't have a way to know that all descendants have completed.
                        throw new Error("descendantsComplete event not supported for bindings on this node");
                    }
                }
            }
        },

        startPossiblyAsyncContentBinding: (node, bindingContext) => {
            var bindingInfo = ko.utils.domData.getOrSet(node, boundElementDomDataKey, {});

            if (!bindingInfo.asyncContext) {
                bindingInfo.asyncContext = new AsyncCompleteContext(node, bindingInfo, bindingContext[contextAncestorBindingInfo]);
            }

            // If the provided context was already extended with this node's binding info, just return the extended context
            if (bindingContext[contextAncestorBindingInfo] == bindingInfo) {
                return bindingContext;
            }

            return bindingContext['extend'](ctx => {
                ctx[contextAncestorBindingInfo] = bindingInfo;
            });
        }
    };

    // Given a function that returns bindings, create and return a new object that contains
    // binding value-accessors functions. Each accessor function calls the original function
    // so that it always gets the latest value and all dependencies are captured. This is used
    // by ko.applyBindingsToNode and getBindingsAndMakeAccessors.
    function makeAccessorsFromFunction(callback) {
        return ko.utils.objectMap(ko.dependencyDetection.ignore(callback), (value, key) =>
            () => callback()[key]
        );
    }

    // Given a bindings function or object, create and return a new object that contains
    // binding value-accessors functions. This is used by ko.applyBindingsToNode.
    function makeBindingAccessors(bindings, context, node) {
        return (typeof bindings === 'function')
            ? makeAccessorsFromFunction(bindings.bind(null, context, node))
            : ko.utils.objectMap(bindings, value => () => value);
    }

    // This function is used if the binding provider doesn't include a getBindingAccessors function.
    // It must be called with 'this' set to the provider instance.
    function getBindingsAndMakeAccessors(node, context) {
        return makeAccessorsFromFunction(this['getBindings'].bind(this, node, context));
    }

    function validateThatBindingIsAllowedForVirtualElements(bindingName) {
        var validator = ko.virtualElements.allowedBindings[bindingName];
        if (!validator)
            throw new Error("The binding '" + bindingName + "' cannot be used with virtual elements")
    }

    function applyBindingsToDescendantsInternal(bindingContext, elementOrVirtualElement) {
        var nextInQueue = ko.virtualElements.firstChild(elementOrVirtualElement);

        if (nextInQueue) {
            var currentChild,
                provider = ko.bindingProvider['instance'],
                preprocessNode = provider['preprocessNode'];

            // Preprocessing allows a binding provider to mutate a node before bindings are applied to it. For example it's
            // possible to insert new siblings after it, and/or replace the node with a different one. This can be used to
            // implement custom binding syntaxes, such as {{ value }} for string interpolation, or custom element types that
            // trigger insertion of <template> contents at that point in the document.
            if (preprocessNode) {
                while (currentChild = nextInQueue) {
                    nextInQueue = ko.virtualElements.nextSibling(currentChild);
                    preprocessNode.call(provider, currentChild);
                }
                // Reset nextInQueue for the next loop
                nextInQueue = ko.virtualElements.firstChild(elementOrVirtualElement);
            }

            while (currentChild = nextInQueue) {
                // Keep a record of the next child *before* applying bindings, in case the binding removes the current child from its position
                nextInQueue = ko.virtualElements.nextSibling(currentChild);
                applyBindingsToNodeAndDescendantsInternal(bindingContext, currentChild);
            }
        }
        ko.bindingEvent.notify(elementOrVirtualElement, ko.bindingEvent.childrenComplete);
    }

    function applyBindingsToNodeAndDescendantsInternal(bindingContext, nodeVerified) {
        var bindingContextForDescendants = bindingContext;

        var isElement = (nodeVerified.nodeType === 1);

        // Perf optimisation: Apply bindings only if...
        // (1) We need to store the binding info for the node (all element nodes)
        // (2) It might have bindings (e.g., it has a data-bind attribute, or it's a marker for a containerless template)
        var shouldApplyBindings = isElement || ko.bindingProvider['instance']['nodeHasBindings'](nodeVerified);
        if (shouldApplyBindings)
            bindingContextForDescendants = applyBindingsToNodeInternal(nodeVerified, null, bindingContext)['bindingContextForDescendants'];

        if (bindingContextForDescendants && !bindingDoesNotRecurseIntoElementTypes[ko.utils.tagNameLower(nodeVerified)]) {
            applyBindingsToDescendantsInternal(bindingContextForDescendants, nodeVerified);
        }
    }

    function topologicalSortBindings(bindings) {
        // Depth-first sort
        var result = [],                // The list of key/handler pairs that we will return
            bindingsConsidered = {},    // A temporary record of which bindings are already in 'result'
            cyclicDependencyStack = []; // Keeps track of a depth-search so that, if there's a cycle, we know which bindings caused it
        ko.utils.objectForEach(bindings, function pushBinding(bindingKey) {
            if (!bindingsConsidered[bindingKey]) {
                var binding = ko['getBindingHandler'](bindingKey);
                if (binding) {
                    // First add dependencies (if any) of the current binding
                    if (binding['after']) {
                        cyclicDependencyStack.push(bindingKey);
                        ko.utils.arrayForEach(binding['after'], bindingDependencyKey => {
                            if (bindings[bindingDependencyKey]) {
                                if (ko.utils.arrayIndexOf(cyclicDependencyStack, bindingDependencyKey) !== -1) {
                                    throw Error("Cannot combine the following bindings, because they have a cyclic dependency: " + cyclicDependencyStack.join(", "));
                                } else {
                                    pushBinding(bindingDependencyKey);
                                }
                            }
                        });
                        cyclicDependencyStack.length--;
                    }
                    // Next add the current binding
                    result.push({ key: bindingKey, handler: binding });
                }
                bindingsConsidered[bindingKey] = true;
            }
        });

        return result;
    }

    function applyBindingsToNodeInternal(node, sourceBindings, bindingContext) {
        var bindingInfo = ko.utils.domData.getOrSet(node, boundElementDomDataKey, {});

        // Prevent multiple applyBindings calls for the same node, except when a binding value is specified
        var alreadyBound = bindingInfo.alreadyBound;
        if (!sourceBindings) {
            if (alreadyBound) {
                throw Error("You cannot apply bindings multiple times to the same element.");
            }
            bindingInfo.alreadyBound = true;
        }
        if (!alreadyBound) {
            bindingInfo.context = bindingContext;
        }
        if (!bindingInfo.notifiedEvents) {
            bindingInfo.notifiedEvents = {};
        }

        // Use bindings if given, otherwise fall back on asking the bindings provider to give us some bindings
        var bindings;
        if (sourceBindings && typeof sourceBindings !== 'function') {
            bindings = sourceBindings;
        } else {
            var provider = ko.bindingProvider['instance'],
                getBindings = provider['getBindingAccessors'] || getBindingsAndMakeAccessors;

            // Get the binding from the provider within a computed observable so that we can update the bindings whenever
            // the binding context is updated or if the binding provider accesses observables.
            var bindingsUpdater = ko.computed(
                () => {
                    bindings = sourceBindings ? sourceBindings(bindingContext, node) : getBindings.call(provider, node, bindingContext);
                    // Register a dependency on the binding context to support observable view models.
                    if (bindings) {
                        if (bindingContext[contextSubscribable]) {
                            bindingContext[contextSubscribable]();
                        }
                        if (bindingContext[contextDataDependency]) {
                            bindingContext[contextDataDependency]();
                        }
                    }
                    return bindings;
                },
                null, { disposeWhenNodeIsRemoved: node }
            );

            if (!bindings || !bindingsUpdater.isActive())
                bindingsUpdater = null;
        }

        var contextToExtend = bindingContext;
        var bindingHandlerThatControlsDescendantBindings;
        if (bindings) {
            // Return the value accessor for a given binding. When bindings are static (won't be updated because of a binding
            // context update), just return the value accessor from the binding. Otherwise, return a function that always gets
            // the latest binding value and registers a dependency on the binding updater.
            var getValueAccessor = bindingsUpdater
                ? bindingKey => () => bindingsUpdater()[bindingKey]()
                : bindingKey => bindings[bindingKey];

            // Use of allBindings as a function is maintained for backwards compatibility, but its use is deprecated
            function allBindings() {
                return ko.utils.objectMap(bindingsUpdater ? bindingsUpdater() : bindings, valueAccessor => valueAccessor());
            }
            // The following is the 3.x allBindings API
            allBindings['get'] = key => bindings[key] && getValueAccessor(key)();
            allBindings['has'] = key => key in bindings;

            if (ko.bindingEvent.childrenComplete in bindings) {
                ko.bindingEvent.subscribe(node, ko.bindingEvent.childrenComplete, () => {
                    var callback = bindings[ko.bindingEvent.childrenComplete]();
                    if (callback) {
                        var nodes = ko.virtualElements.childNodes(node);
                        if (nodes.length) {
                            callback(nodes, ko.dataFor(nodes[0]));
                        }
                    }
                });
            }

            if (ko.bindingEvent.descendantsComplete in bindings) {
                contextToExtend = ko.bindingEvent.startPossiblyAsyncContentBinding(node, bindingContext);
                ko.bindingEvent.subscribe(node, ko.bindingEvent.descendantsComplete, () => {
                    var callback = bindings[ko.bindingEvent.descendantsComplete]();
                    if (callback && ko.virtualElements.firstChild(node)) {
                        callback(node);
                    }
                });
            }

            // First put the bindings into the right order
            var orderedBindings = topologicalSortBindings(bindings);

            // Go through the sorted bindings, calling init and update for each
            ko.utils.arrayForEach(orderedBindings, bindingKeyAndHandler => {
                // Note that topologicalSortBindings has already filtered out any nonexistent binding handlers,
                // so bindingKeyAndHandler.handler will always be nonnull.
                var handlerInitFn = bindingKeyAndHandler.handler["init"],
                    handlerUpdateFn = bindingKeyAndHandler.handler["update"],
                    bindingKey = bindingKeyAndHandler.key;

                if (node.nodeType === 8) {
                    validateThatBindingIsAllowedForVirtualElements(bindingKey);
                }

                try {
                    // Run init, ignoring any dependencies
                    if (typeof handlerInitFn == "function") {
                        ko.dependencyDetection.ignore(() => {
                            var initResult = handlerInitFn(node, getValueAccessor(bindingKey), allBindings, contextToExtend['$data'], contextToExtend);

                            // If this binding handler claims to control descendant bindings, make a note of this
                            if (initResult && initResult['controlsDescendantBindings']) {
                                if (bindingHandlerThatControlsDescendantBindings !== undefined)
                                    throw new Error("Multiple bindings (" + bindingHandlerThatControlsDescendantBindings + " and " + bindingKey + ") are trying to control descendant bindings of the same element. You cannot use these bindings together on the same element.");
                                bindingHandlerThatControlsDescendantBindings = bindingKey;
                            }
                        });
                    }

                    // Run update in its own computed wrapper
                    if (typeof handlerUpdateFn == "function") {
                        ko.computed(
                            () => handlerUpdateFn(node, getValueAccessor(bindingKey), allBindings, contextToExtend['$data'], contextToExtend),
                            null,
                            { disposeWhenNodeIsRemoved: node }
                        );
                    }
                } catch (ex) {
                    ex.message = "Unable to process binding \"" + bindingKey + ": " + bindings[bindingKey] + "\"\nMessage: " + ex.message;
                    throw ex;
                }
            });
        }

        var shouldBindDescendants = bindingHandlerThatControlsDescendantBindings === undefined;
        return {
            'shouldBindDescendants': shouldBindDescendants,
            'bindingContextForDescendants': shouldBindDescendants && contextToExtend
        };
    }

    ko.storedBindingContextForNode = node => {
        var bindingInfo = ko.utils.domData.get(node, boundElementDomDataKey);
        return bindingInfo && bindingInfo.context;
    }

    function getBindingContext(viewModelOrBindingContext, extendContextCallback) {
        return viewModelOrBindingContext && (viewModelOrBindingContext instanceof ko.bindingContext)
            ? viewModelOrBindingContext
            : new ko.bindingContext(viewModelOrBindingContext, undefined, undefined, extendContextCallback);
    }

    ko.applyBindingAccessorsToNode = (node, bindings, viewModelOrBindingContext) =>
        applyBindingsToNodeInternal(node, bindings, getBindingContext(viewModelOrBindingContext));

    ko.applyBindingsToNode = (node, bindings, viewModelOrBindingContext) => {
        var context = getBindingContext(viewModelOrBindingContext);
        return ko.applyBindingAccessorsToNode(node, makeBindingAccessors(bindings, context, node), context);
    };

    ko.applyBindingsToDescendants = (viewModelOrBindingContext, rootNode) => {
        if (rootNode.nodeType === 1 || rootNode.nodeType === 8)
            applyBindingsToDescendantsInternal(getBindingContext(viewModelOrBindingContext), rootNode);
    };

    ko.applyBindings = function (viewModelOrBindingContext, rootNode, extendContextCallback) {
        if (arguments.length < 2) {
            rootNode = document.body;
            if (!rootNode) {
                throw Error("ko.applyBindings: could not find document.body; has the document been loaded?");
            }
        } else if (!rootNode || (rootNode.nodeType !== 1 && rootNode.nodeType !== 8)) {
            throw Error("ko.applyBindings: first parameter should be your view model; second parameter should be a DOM node");
        }

        applyBindingsToNodeAndDescendantsInternal(getBindingContext(viewModelOrBindingContext, extendContextCallback), rootNode);
    };

    // Retrieving binding context from arbitrary nodes
    ko.dataFor = node => {
        // We can only do something meaningful for elements and comment nodes (in particular, not text nodes, as IE can't store domdata for them)
        var context = node && [1,8].includes(node.nodeType) && ko.storedBindingContextForNode(node);
        return context ? context['$data'] : undefined;
    };

    ko.exportSymbol('bindingHandlers', ko.bindingHandlers);
    ko.exportSymbol('applyBindings', ko.applyBindings);
    ko.exportSymbol('applyBindingAccessorsToNode', ko.applyBindingAccessorsToNode);
    ko.exportSymbol('dataFor', ko.dataFor);
})();
(() => {
    var loadingSubscribablesCache = {}, // Tracks component loads that are currently in flight
        loadedDefinitionsCache = {};    // Tracks component loads that have already completed

    ko.components = {
        get: (componentName, callback) => {
            var cachedDefinition = getObjectOwnProperty(loadedDefinitionsCache, componentName);
            if (cachedDefinition) {
                // It's already loaded and cached. Reuse the same definition object.
                // Note that for API consistency, even cache hits complete asynchronously by default.
                // You can bypass this by putting synchronous:true on your component config.
                if (cachedDefinition.isSynchronousComponent) {
                    ko.dependencyDetection.ignore(() => // See comment in loaderRegistryBehaviors.js for reasoning
                        callback(cachedDefinition.definition)
                    );
                } else {
                    ko.tasks.schedule(() => callback(cachedDefinition.definition) );
                }
            } else {
                // Join the loading process that is already underway, or start a new one.
                loadComponentAndNotify(componentName, callback);
            }
        },

        clearCachedDefinition: componentName =>
            delete loadedDefinitionsCache[componentName]
        ,

        _getFirstResultFromLoaders: getFirstResultFromLoaders
    };

    function getObjectOwnProperty(obj, propName) {
        return Object.prototype.hasOwnProperty.call(obj, propName) ? obj[propName] : undefined;
    }

    function loadComponentAndNotify(componentName, callback) {
        var subscribable = getObjectOwnProperty(loadingSubscribablesCache, componentName),
            completedAsync;
        if (!subscribable) {
            // It's not started loading yet. Start loading, and when it's done, move it to loadedDefinitionsCache.
            subscribable = loadingSubscribablesCache[componentName] = new ko.subscribable();
            subscribable.subscribe(callback);

            beginLoadingComponent(componentName, (definition, config) => {
                var isSynchronousComponent = !!(config && config['synchronous']);
                loadedDefinitionsCache[componentName] = { definition: definition, isSynchronousComponent: isSynchronousComponent };
                delete loadingSubscribablesCache[componentName];

                // For API consistency, all loads complete asynchronously. However we want to avoid
                // adding an extra task schedule if it's unnecessary (i.e., the completion is already
                // async).
                //
                // You can bypass the 'always asynchronous' feature by putting the synchronous:true
                // flag on your component configuration when you register it.
                if (completedAsync || isSynchronousComponent) {
                    // Note that notifySubscribers ignores any dependencies read within the callback.
                    // See comment in loaderRegistryBehaviors.js for reasoning
                    subscribable['notifySubscribers'](definition);
                } else {
                    ko.tasks.schedule(() => subscribable['notifySubscribers'](definition));
                }
            });
            completedAsync = true;
        } else {
            subscribable.subscribe(callback);
        }
    }

    function beginLoadingComponent(componentName, callback) {
        getFirstResultFromLoaders('getConfig', [componentName], config => {
            if (config) {
                // We have a config, so now load its definition
                getFirstResultFromLoaders('loadComponent', [componentName, config], definition =>
                    callback(definition, config)
                );
            } else {
                // The component has no config - it's unknown to all the loaders.
                // Note that this is not an error (e.g., a module loading error) - that would abort the
                // process and this callback would not run. For this callback to run, all loaders must
                // have confirmed they don't know about this component.
                callback(null, null);
            }
        });
    }

    function getFirstResultFromLoaders(methodName, argsExceptCallback, callback, candidateLoaders) {
        // On the first call in the stack, start with the full set of loaders
        if (!candidateLoaders) {
            candidateLoaders = ko.components['loaders'].slice(0); // Use a copy, because we'll be mutating this array
        }

        // Try the next candidate
        var currentCandidateLoader = candidateLoaders.shift();
        if (currentCandidateLoader) {
            var methodInstance = currentCandidateLoader[methodName];
            if (methodInstance) {
                var wasAborted = false,
                    synchronousReturnValue = methodInstance.apply(currentCandidateLoader, argsExceptCallback.concat(function(result) {
                        if (wasAborted) {
                            callback(null);
                        } else if (result !== null) {
                            // This candidate returned a value. Use it.
                            callback(result);
                        } else {
                            // Try the next candidate
                            getFirstResultFromLoaders(methodName, argsExceptCallback, callback, candidateLoaders);
                        }
                    }));

                // Currently, loaders may not return anything synchronously. This leaves open the possibility
                // that we'll extend the API to support synchronous return values in the future. It won't be
                // a breaking change, because currently no loader is allowed to return anything except undefined.
                if (synchronousReturnValue !== undefined) {
                    wasAborted = true;

                    // Method to suppress exceptions will remain undocumented. This is only to keep
                    // KO's specs running tidily, since we can observe the loading got aborted without
                    // having exceptions cluttering up the console too.
                    if (!currentCandidateLoader['suppressLoaderExceptions']) {
                        throw new Error('Component loaders must supply values by invoking the callback, not by returning values synchronously.');
                    }
                }
            } else {
                // This candidate doesn't have the relevant handler. Synchronously move on to the next one.
                getFirstResultFromLoaders(methodName, argsExceptCallback, callback, candidateLoaders);
            }
        } else {
            // No candidates returned a value
            callback(null);
        }
    }

    // Reference the loaders via string name so it's possible for developers
    // to replace the whole array by assigning to ko.components.loaders
    ko.components['loaders'] = [];

    ko.exportSymbol('components', ko.components);
})();
(() => {

    // The default loader is responsible for two things:
    // 1. Maintaining the default in-memory registry of component configuration objects
    //    (i.e., the thing you're writing to when you call ko.components.register(someName, ...))
    // 2. Answering requests for components by fetching configuration objects
    //    from that default in-memory registry and resolving them into standard
    //    component definition objects (of the form { createViewModel: ..., template: ... })
    // Custom loaders may override either of these facilities, i.e.,
    // 1. To supply configuration objects from some other source (e.g., conventions)
    // 2. Or, to resolve configuration objects by loading viewmodels/templates via arbitrary logic.

    var defaultConfigRegistry = {};

    ko.components.register = (componentName, config) => {
        if (!config) {
            throw new Error('Invalid configuration for ' + componentName);
        }

        if (ko.components.isRegistered(componentName)) {
            throw new Error('Component ' + componentName + ' is already registered');
        }

        defaultConfigRegistry[componentName] = config;
    };

    ko.components.isRegistered = componentName =>
        Object.prototype.hasOwnProperty.call(defaultConfigRegistry, componentName);

    ko.components.unregister = componentName => {
        delete defaultConfigRegistry[componentName];
        ko.components.clearCachedDefinition(componentName);
    };

    ko.components.defaultLoader = {
        'getConfig': (componentName, callback) => {
            var result = ko.components.isRegistered(componentName)
                ? defaultConfigRegistry[componentName]
                : null;
            callback(result);
        },

        'loadComponent': (componentName, config, callback) => {
            var errorCallback = makeErrorCallback(componentName);
            resolveConfig(componentName, errorCallback, config, callback);
        },

        'loadTemplate': (componentName, templateConfig, callback) =>
            resolveTemplate(makeErrorCallback(componentName), templateConfig, callback)
        ,

        'loadViewModel': (componentName, viewModelConfig, callback) =>
            resolveViewModel(makeErrorCallback(componentName), viewModelConfig, callback)
    };

    var createViewModelKey = 'createViewModel';

    // Takes a config object of the form { template: ..., viewModel: ... }, and asynchronously convert it
    // into the standard component definition format:
    //    { template: <ArrayOfDomNodes>, createViewModel: function(params, componentInfo) { ... } }.
    // Since both template and viewModel may need to be resolved asynchronously, both tasks are performed
    // in parallel, and the results joined when both are ready. We don't depend on any promises infrastructure,
    // so this is implemented manually below.
    function resolveConfig(componentName, errorCallback, config, callback) {
        var result = {},
            makeCallBackWhenZero = 2,
            tryIssueCallback = () => {
                if (--makeCallBackWhenZero === 0) {
                    callback(result);
                }
            },
            templateConfig = config['template'],
            viewModelConfig = config['viewModel'];

        if (templateConfig) {
            ko.components._getFirstResultFromLoaders('loadTemplate', [componentName, templateConfig], resolvedTemplate => {
                result['template'] = resolvedTemplate;
                tryIssueCallback();
            });
        } else {
            tryIssueCallback();
        }

        if (viewModelConfig) {
            ko.components._getFirstResultFromLoaders('loadViewModel', [componentName, viewModelConfig], resolvedViewModel => {
                result[createViewModelKey] = resolvedViewModel;
                tryIssueCallback();
            });
        } else {
            tryIssueCallback();
        }
    }

    function resolveTemplate(errorCallback, templateConfig, callback) {
        if (typeof templateConfig === 'string') {
            // Markup - parse it
            callback(ko.utils.parseHtmlFragment(templateConfig));
        } else if (templateConfig instanceof Array) {
            // Assume already an array of DOM nodes - pass through unchanged
            callback(templateConfig);
        } else if (templateConfig instanceof DocumentFragment) {
            // Document fragment - use its child nodes
            callback(ko.utils.makeArray(templateConfig.childNodes));
        } else if (templateConfig['element']) {
            var element = templateConfig['element'];
            if (element instanceof HTMLElement) {
                // Element instance - copy its child nodes
                callback(cloneNodesFromTemplateSourceElement(element));
            } else if (typeof element === 'string') {
                // Element ID - find it, then copy its child nodes
                var elemInstance = document.getElementById(element);
                if (elemInstance) {
                    callback(cloneNodesFromTemplateSourceElement(elemInstance));
                } else {
                    errorCallback('Cannot find element with ID ' + element);
                }
            } else {
                errorCallback('Unknown element type: ' + element);
            }
        } else {
            errorCallback('Unknown template value: ' + templateConfig);
        }
    }

    function resolveViewModel(errorCallback, viewModelConfig, callback) {
        if (typeof viewModelConfig === 'function') {
            // Constructor - convert to standard factory function format
            // By design, this does *not* supply componentInfo to the constructor, as the intent is that
            // componentInfo contains non-viewmodel data (e.g., the component's element) that should only
            // be used in factory functions, not viewmodel constructors.
            callback(params => new viewModelConfig(params));
        } else if (typeof viewModelConfig[createViewModelKey] === 'function') {
            // Already a factory function - use it as-is
            callback(viewModelConfig[createViewModelKey]);
        } else if ('instance' in viewModelConfig) {
            // Fixed object instance - promote to createViewModel format for API consistency
            var fixedInstance = viewModelConfig['instance'];
            callback(() => fixedInstance);
        } else if ('viewModel' in viewModelConfig) {
            // Resolved AMD module whose value is of the form { viewModel: ... }
            resolveViewModel(errorCallback, viewModelConfig['viewModel'], callback);
        } else {
            errorCallback('Unknown viewModel value: ' + viewModelConfig);
        }
    }

    function cloneNodesFromTemplateSourceElement(elemInstance) {
        if ('template' == ko.utils.tagNameLower(elemInstance)) {
            // For browsers with proper <template> element support (i.e., where the .content property
            // gives a document fragment), use that document fragment.
            if (elemInstance.content instanceof DocumentFragment) {
                return ko.utils.cloneNodes(elemInstance.content.childNodes);
            }
        }
        throw 'Template Source Element not a <template>';
    }

    function makeErrorCallback(componentName) {
        return message => {
            throw new Error('Component \'' + componentName + '\': ' + message)
        };
    }

    ko.exportSymbol('components.register', ko.components.register);

    // By default, the default loader is the only registered component loader
    ko.components['loaders'].push(ko.components.defaultLoader);
})();
(() => {
    // Overridable API for determining which component name applies to a given node. By overriding this,
    // you can for example map specific tagNames to components that are not preregistered.
    ko.components['getComponentNameForNode'] = node => {
        var tagNameLower = ko.utils.tagNameLower(node);
        if (ko.components.isRegistered(tagNameLower)) {
            // Try to determine that this node can be considered a *custom* element; see https://github.com/knockout/knockout/issues/1603
            if (tagNameLower.indexOf('-') != -1 || ('' + node) == "[object HTMLUnknownElement]") {
                return tagNameLower;
            }
        }
    };

    ko.components.addBindingsForCustomElement = (allBindings, node, bindingContext, valueAccessors) => {
        // Determine if it's really a custom element matching a component
        if (node.nodeType === 1) {
            var componentName = ko.components['getComponentNameForNode'](node);
            if (componentName) {
                // It does represent a component, so add a component binding for it
                allBindings = allBindings || {};

                if (allBindings['component']) {
                    // Avoid silently overwriting some other 'component' binding that may already be on the element
                    throw new Error('Cannot use the "component" binding on a custom element matching a component');
                }

                var componentBindingValue = { 'name': componentName, 'params': getComponentParamsFromCustomElement(node, bindingContext) };

                allBindings['component'] = valueAccessors
                    ? () => componentBindingValue
                    : componentBindingValue;
            }
        }

        return allBindings;
    }

    var nativeBindingProviderInstance = new ko.bindingProvider();

    function getComponentParamsFromCustomElement(elem, bindingContext) {
        var paramsAttribute = elem.getAttribute('params');

        if (paramsAttribute) {
            var params = nativeBindingProviderInstance['parseBindingsString'](paramsAttribute, bindingContext, elem, { 'valueAccessors': true, 'bindingParams': true }),
                rawParamComputedValues = ko.utils.objectMap(params, paramValue =>
                    ko.computed(paramValue, null, { disposeWhenNodeIsRemoved: elem })
                ),
                result = ko.utils.objectMap(rawParamComputedValues, paramValueComputed => {
                    var paramValue = paramValueComputed.peek();
                    // Does the evaluation of the parameter value unwrap any observables?
                    if (!paramValueComputed.isActive()) {
                        // No it doesn't, so there's no need for any computed wrapper. Just pass through the supplied value directly.
                        // Example: "someVal: firstName, age: 123" (whether or not firstName is an observable/computed)
                        return paramValue;
                    } else {
                        // Yes it does. Supply a computed property that unwraps both the outer (binding expression)
                        // level of observability, and any inner (resulting model value) level of observability.
                        // This means the component doesn't have to worry about multiple unwrapping. If the value is a
                        // writable observable, the computed will also be writable and pass the value on to the observable.
                        return ko.computed({
                            'read': () => ko.utils.unwrapObservable(paramValueComputed()),
                            'write': ko.isWriteableObservable(paramValue) && (value => paramValueComputed()(value)),
                            disposeWhenNodeIsRemoved: elem
                        });
                    }
                });

            // Give access to the raw computeds, as long as that wouldn't overwrite any custom param also called '$raw'
            // This is in case the developer wants to react to outer (binding) observability separately from inner
            // (model value) observability, or in case the model value observable has subobservables.
            if (!Object.prototype.hasOwnProperty.call(result, '$raw')) {
                result['$raw'] = rawParamComputedValues;
            }

            return result;
        }
        // For consistency, absence of a "params" attribute is treated the same as the presence of
        // any empty one. Otherwise component viewmodels need special code to check whether or not
        // 'params' or 'params.$raw' is null/undefined before reading subproperties, which is annoying.
        return { '$raw': {} };
    }
})();
(() => {
    var componentLoadingOperationUniqueId = 0;

    ko.bindingHandlers['component'] = {
        'init': (element, valueAccessor, ignored1, ignored2, bindingContext) => {
            var currentViewModel,
                currentLoadingOperationId,
                afterRenderSub,
                disposeAssociatedComponentViewModel = () => {
                    var currentViewModelDispose = currentViewModel && currentViewModel['dispose'];
                    if (typeof currentViewModelDispose === 'function') {
                        currentViewModelDispose.call(currentViewModel);
                    }
                    if (afterRenderSub) {
                        afterRenderSub.dispose();
                    }
                    afterRenderSub = null;
                    currentViewModel = null;
                    // Any in-flight loading operation is no longer relevant, so make sure we ignore its completion
                    currentLoadingOperationId = null;
                },
                originalChildNodes = ko.utils.makeArray(ko.virtualElements.childNodes(element));

            ko.virtualElements.emptyNode(element);
            ko.utils.domNodeDisposal.addDisposeCallback(element, disposeAssociatedComponentViewModel);

            ko.computed(() => {
                var value = ko.utils.unwrapObservable(valueAccessor()),
                    componentName, componentParams;

                if (typeof value === 'string') {
                    componentName = value;
                } else {
                    componentName = ko.utils.unwrapObservable(value['name']);
                    componentParams = ko.utils.unwrapObservable(value['params']);
                }

                if (!componentName) {
                    throw new Error('No component name specified');
                }

                var asyncContext = ko.bindingEvent.startPossiblyAsyncContentBinding(element, bindingContext);

                var loadingOperationId = currentLoadingOperationId = ++componentLoadingOperationUniqueId;
                ko.components.get(componentName, componentDefinition => {
                    // If this is not the current load operation for this element, ignore it.
                    if (currentLoadingOperationId !== loadingOperationId) {
                        return;
                    }

                    // Clean up previous state
                    disposeAssociatedComponentViewModel();

                    // Instantiate and bind new component. Implicitly this cleans any old DOM nodes.
                    if (!componentDefinition) {
                        throw new Error('Unknown component \'' + componentName + '\'');
                    }
                    cloneTemplateIntoElement(componentName, componentDefinition, element);

                    var componentInfo = {
                        'element': element,
                        'templateNodes': originalChildNodes
                    };

                    var componentViewModel = createViewModel(componentDefinition, componentParams, componentInfo),
                        childBindingContext = asyncContext['createChildContext'](componentViewModel, {
                            'extend': ctx => {
                                ctx['$component'] = componentViewModel;
                                ctx['$componentTemplateNodes'] = originalChildNodes;
                            }
                        });

                    if (componentViewModel && componentViewModel['koDescendantsComplete']) {
                        afterRenderSub = ko.bindingEvent.subscribe(element, ko.bindingEvent.descendantsComplete, componentViewModel['koDescendantsComplete'], componentViewModel);
                    }

                    currentViewModel = componentViewModel;
                    ko.applyBindingsToDescendants(childBindingContext, element);
                });
            }, null, { disposeWhenNodeIsRemoved: element });

            return { 'controlsDescendantBindings': true };
        }
    };

    ko.virtualElements.allowedBindings['component'] = true;

    function cloneTemplateIntoElement(componentName, componentDefinition, element) {
        var template = componentDefinition['template'];
        if (!template) {
            throw new Error('Component \'' + componentName + '\' has no template');
        }

        var clonedNodesArray = ko.utils.cloneNodes(template);
        ko.virtualElements.setDomNodeChildren(element, clonedNodesArray);
    }

    function createViewModel(componentDefinition, componentParams, componentInfo) {
        var componentViewModelFactory = componentDefinition['createViewModel'];
        return componentViewModelFactory
            ? componentViewModelFactory.call(componentDefinition, componentParams, componentInfo)
            : componentParams; // Template-only component
    }

})();
var attrHtmlToJavaScriptMap = { 'class': 'className', 'for': 'htmlFor' };
ko.bindingHandlers['attr'] = {
    'update': (element, valueAccessor, allBindings) => {
        var value = ko.utils.unwrapObservable(valueAccessor()) || {};
        ko.utils.objectForEach(value, function(attrName, attrValue) {
            attrValue = ko.utils.unwrapObservable(attrValue);

            // Find the namespace of this attribute, if any.
            var prefixLen = attrName.indexOf(':');
            var namespace = "lookupNamespaceURI" in element && prefixLen > 0 && element.lookupNamespaceURI(attrName.substr(0, prefixLen));

            // To cover cases like "attr: { checked:someProp }", we want to remove the attribute entirely
            // when someProp is a "no value"-like value (strictly null, false, or undefined)
            // (because the absence of the "checked" attr is how to mark an element as not checked, etc.)
            var toRemove = (attrValue === false) || (attrValue === null) || (attrValue === undefined);
            if (toRemove) {
                namespace ? element.removeAttributeNS(namespace, attrName) : element.removeAttribute(attrName);
            } else {
                attrValue = attrValue.toString();
            }

            if (!toRemove) {
                namespace ? element.setAttributeNS(namespace, attrName, attrValue) : element.setAttribute(attrName, attrValue);
            }

            // Treat "name" specially - although you can think of it as an attribute, it also needs
            // special handling on older versions of IE (https://github.com/SteveSanderson/knockout/pull/333)
            // Deliberately being case-sensitive here because XHTML would regard "Name" as a different thing
            // entirely, and there's no strong reason to allow for such casing in HTML.
            if (attrName === "name") {
                element.name = toRemove ? "" : attrValue;
            }
        });
    }
};
var classesWrittenByBindingKey = '__ko__cssValue';

ko.bindingHandlers['css'] = {
    'update': (element, valueAccessor) => {
        var value = ko.utils.unwrapObservable(valueAccessor());
        if (value !== null && typeof value == "object") {
            ko.utils.objectForEach(value, (className, shouldHaveClass) => {
                shouldHaveClass = ko.utils.unwrapObservable(shouldHaveClass);
                ko.utils.toggleDomNodeCssClass(element, className, shouldHaveClass);
            });
        } else {
            value = ko.utils.stringTrim(value);
            ko.utils.toggleDomNodeCssClass(element, element[classesWrittenByBindingKey], false);
            element[classesWrittenByBindingKey] = value;
            ko.utils.toggleDomNodeCssClass(element, value, true);
        }
    }
};
ko.bindingHandlers['enable'] = {
    'update': (element, valueAccessor) => {
        var value = ko.utils.unwrapObservable(valueAccessor());
        if (value && element.disabled)
            element.removeAttribute("disabled");
        else if ((!value) && (!element.disabled))
            element.disabled = true;
    }
};

ko.bindingHandlers['disable'] = {
    'update': (element, valueAccessor) =>
        ko.bindingHandlers['enable']['update'](element, () => !ko.utils.unwrapObservable(valueAccessor()))
};
// For certain common events (currently just 'click'), allow a simplified data-binding syntax
// e.g. click:handler instead of the usual full-length event:{click:handler}
function makeEventHandlerShortcut(eventName) {
    ko.bindingHandlers[eventName] = {
        'init': function(element, valueAccessor, allBindings, viewModel, bindingContext) {
            var newValueAccessor = () => {
                var result = {};
                result[eventName] = valueAccessor();
                return result;
            };
            return ko.bindingHandlers['event']['init'].call(this, element, newValueAccessor, allBindings, viewModel, bindingContext);
        }
    }
}

ko.bindingHandlers['event'] = {
    'init' : (element, valueAccessor, allBindings, viewModel, bindingContext) => {
        var eventsToHandle = valueAccessor() || {};
        ko.utils.objectForEach(eventsToHandle, eventName => {
            if (typeof eventName == "string") {
                ko.utils.registerEventHandler(element, eventName, function (event) {
                    var handlerReturnValue;
                    var handlerFunction = valueAccessor()[eventName];
                    if (!handlerFunction)
                        return;

                    try {
                        // Take all the event args, and prefix with the viewmodel
                        var argsForHandler = ko.utils.makeArray(arguments);
                        viewModel = bindingContext['$data'];
                        argsForHandler.unshift(viewModel);
                        handlerReturnValue = handlerFunction.apply(viewModel, argsForHandler);
                    } finally {
                        if (handlerReturnValue !== true) { // Normally we want to prevent default action. Developer can override this be explicitly returning true.
                            if (event.preventDefault)
                                event.preventDefault();
                            else
                                event.returnValue = false;
                        }
                    }

                    var bubble = allBindings.get(eventName + 'Bubble') !== false;
                    if (!bubble) {
                        event.cancelBubble = true;
                        if (event.stopPropagation)
                            event.stopPropagation();
                    }
                });
            }
        });
    }
};
// "foreach: someExpression" is equivalent to "template: { foreach: someExpression }"
// "foreach: { data: someExpression, afterAdd: myfn }" is equivalent to "template: { foreach: someExpression, afterAdd: myfn }"
ko.bindingHandlers['foreach'] = {
    makeTemplateValueAccessor: valueAccessor => {
        return () => {
            var modelValue = valueAccessor(),
                unwrappedValue = ko.utils.peekObservable(modelValue);    // Unwrap without setting a dependency here

            // If unwrappedValue is the array, pass in the wrapped value on its own
            // The value will be unwrapped and tracked within the template binding
            // (See https://github.com/SteveSanderson/knockout/issues/523)
            if ((!unwrappedValue) || typeof unwrappedValue.length == "number")
                return { 'foreach': modelValue, 'templateEngine': ko.nativeTemplateEngine.instance };

            // If unwrappedValue.data is the array, preserve all relevant options and unwrap again value so we get updates
            ko.utils.unwrapObservable(modelValue);
            return {
                'foreach': unwrappedValue['data'],
                'as': unwrappedValue['as'],
                'noChildContext': unwrappedValue['noChildContext'],
                'includeDestroyed': unwrappedValue['includeDestroyed'],
                'afterAdd': unwrappedValue['afterAdd'],
                'beforeRemove': unwrappedValue['beforeRemove'],
                'afterRender': unwrappedValue['afterRender'],
                'beforeMove': unwrappedValue['beforeMove'],
                'afterMove': unwrappedValue['afterMove'],
                'templateEngine': ko.nativeTemplateEngine.instance
            };
        };
    },
    'init': (element, valueAccessor) =>
        ko.bindingHandlers['template']['init'](element, ko.bindingHandlers['foreach'].makeTemplateValueAccessor(valueAccessor))
    ,
    'update': (element, valueAccessor, allBindings, viewModel, bindingContext) =>
        ko.bindingHandlers['template']['update'](element, ko.bindingHandlers['foreach'].makeTemplateValueAccessor(valueAccessor), allBindings, viewModel, bindingContext)
};
ko.expressionRewriting.bindingRewriteValidators['foreach'] = false; // Can't rewrite control flow bindings
ko.virtualElements.allowedBindings['foreach'] = true;
var hasfocusUpdatingProperty = '__ko_hasfocusUpdating';
var hasfocusLastValue = '__ko_hasfocusLastValue';
ko.bindingHandlers['hasfocus'] = {
    'init': (element, valueAccessor, allBindings) => {
        var handleElementFocusChange = isFocused => {
            // Where possible, ignore which event was raised and determine focus state using activeElement,
            // as this avoids phantom focus/blur events raised when changing tabs in modern browsers.
            // However, not all KO-targeted browsers (Firefox 2) support activeElement. For those browsers,
            // prevent a loss of focus when changing tabs/windows by setting a flag that prevents hasfocus
            // from calling 'blur()' on the element when it loses focus.
            // Discussion at https://github.com/SteveSanderson/knockout/pull/352
            element[hasfocusUpdatingProperty] = true;
            isFocused = (element.ownerDocument.activeElement === element);
            var modelValue = valueAccessor();
            ko.expressionRewriting.writeValueToProperty(modelValue, allBindings, 'hasfocus', isFocused, true);

            //cache the latest value, so we can avoid unnecessarily calling focus/blur in the update function
            element[hasfocusLastValue] = isFocused;
            element[hasfocusUpdatingProperty] = false;
        };
        var handleElementFocusIn = handleElementFocusChange.bind(null, true);
        var handleElementFocusOut = handleElementFocusChange.bind(null, false);

        ko.utils.registerEventHandler(element, "focus", handleElementFocusIn);
        ko.utils.registerEventHandler(element, "focusin", handleElementFocusIn);
        ko.utils.registerEventHandler(element, "blur",  handleElementFocusOut);
        ko.utils.registerEventHandler(element, "focusout",  handleElementFocusOut);

        // Assume element is not focused (prevents "blur" being called initially)
        element[hasfocusLastValue] = false;
    },
    'update': (element, valueAccessor) => {
        var value = !!ko.utils.unwrapObservable(valueAccessor());

        if (!element[hasfocusUpdatingProperty] && element[hasfocusLastValue] !== value) {
            value ? element.focus() : element.blur();
        }
    }
};
ko.expressionRewriting.twoWayBindings['hasfocus'] = true;

ko.bindingHandlers['hasFocus'] = ko.bindingHandlers['hasfocus']; // Make "hasFocus" an alias
ko.expressionRewriting.twoWayBindings['hasFocus'] = 'hasfocus';
ko.bindingHandlers['html'] = {
    'init': () => {
        // Prevent binding on the dynamically-injected HTML (as developers are unlikely to expect that, and it has security implications)
        return { 'controlsDescendantBindings': true };
    },
    'update': (element, valueAccessor) =>
        // setHtml will unwrap the value if needed
        ko.utils.setHtml(element, valueAccessor())
};
(function () {

// Makes a binding like with or if
function makeWithIfBinding(bindingKey, isWith, isNot) {
    ko.bindingHandlers[bindingKey] = {
        'init': (element, valueAccessor, allBindings, viewModel, bindingContext) => {
            var didDisplayOnLastUpdate, savedNodes, contextOptions = {}, completeOnRender, needAsyncContext, renderOnEveryChange;

            if (isWith) {
                var as = allBindings.get('as'), noChildContext = allBindings.get('noChildContext');
                renderOnEveryChange = !(as && noChildContext);
                contextOptions = { 'as': as, 'noChildContext': noChildContext, 'exportDependencies': renderOnEveryChange };
            }

            completeOnRender = allBindings.get("completeOn") == "render";
            needAsyncContext = completeOnRender || allBindings['has'](ko.bindingEvent.descendantsComplete);

            ko.computed(() => {
                var value = ko.utils.unwrapObservable(valueAccessor()),
                    shouldDisplay = !isNot !== !value, // equivalent to isNot ? !value : !!value,
                    isInitial = !savedNodes,
                    childContext;

                if (!renderOnEveryChange && shouldDisplay === didDisplayOnLastUpdate) {
                    return;
                }

                if (needAsyncContext) {
                    bindingContext = ko.bindingEvent.startPossiblyAsyncContentBinding(element, bindingContext);
                }

                if (shouldDisplay) {
                    if (!isWith || renderOnEveryChange) {
                        contextOptions['dataDependency'] = ko.computedContext.computed();
                    }

                    if (isWith) {
                        childContext = bindingContext['createChildContext'](typeof value == "function" ? value : valueAccessor, contextOptions);
                    } else if (ko.computedContext.getDependenciesCount()) {
                        childContext = bindingContext['extend'](null, contextOptions);
                    } else {
                        childContext = bindingContext;
                    }
                }

                // Save a copy of the inner nodes on the initial update, but only if we have dependencies.
                if (isInitial && ko.computedContext.getDependenciesCount()) {
                    savedNodes = ko.utils.cloneNodes(ko.virtualElements.childNodes(element), true /* shouldCleanNodes */);
                }

                if (shouldDisplay) {
                    if (!isInitial) {
                        ko.virtualElements.setDomNodeChildren(element, ko.utils.cloneNodes(savedNodes));
                    }

                    ko.applyBindingsToDescendants(childContext, element);
                } else {
                    ko.virtualElements.emptyNode(element);

                    if (!completeOnRender) {
                        ko.bindingEvent.notify(element, ko.bindingEvent.childrenComplete);
                    }
                }

                didDisplayOnLastUpdate = shouldDisplay;

            }, null, { disposeWhenNodeIsRemoved: element });

            return { 'controlsDescendantBindings': true };
        }
    };
    ko.expressionRewriting.bindingRewriteValidators[bindingKey] = false; // Can't rewrite control flow bindings
    ko.virtualElements.allowedBindings[bindingKey] = true;
}

// Construct the actual binding handlers
makeWithIfBinding('if');
makeWithIfBinding('ifnot', false /* isWith */, true /* isNot */);
makeWithIfBinding('with', true /* isWith */);

})();
var captionPlaceholder = {};
ko.bindingHandlers['options'] = {
    'init': element => {
        if (ko.utils.tagNameLower(element) !== "select")
            throw new Error("options binding applies only to SELECT elements");

        // Remove all existing <option>s.
        while (element.length > 0) {
            element.remove(0);
        }

        // Ensures that the binding processor doesn't try to bind the options
        return { 'controlsDescendantBindings': true };
    },
    'update': (element, valueAccessor, allBindings) => {
        function selectedOptions() {
            return Array.from(element.options).filter(node => node.selected);
        }

        var selectWasPreviouslyEmpty = element.length == 0,
            multiple = element.multiple,
            previousScrollTop = (!selectWasPreviouslyEmpty && multiple) ? element.scrollTop : null,
            unwrappedArray = ko.utils.unwrapObservable(valueAccessor()),
            valueAllowUnset = allBindings.get('valueAllowUnset') && allBindings['has']('value'),
            arrayToDomNodeChildrenOptions = {},
            captionValue,
            filteredArray,
            previousSelectedValues = [];

        if (!valueAllowUnset) {
            if (multiple) {
                previousSelectedValues = selectedOptions().map(ko.selectExtensions.readValue);
            } else if (element.selectedIndex >= 0) {
                previousSelectedValues.push(ko.selectExtensions.readValue(element.options[element.selectedIndex]));
            }
        }

        if (unwrappedArray) {
            if (typeof unwrappedArray.length == "undefined") // Coerce single value into array
                unwrappedArray = [unwrappedArray];

            // Filter out any entries marked as destroyed
            filteredArray = unwrappedArray.filter(item => item || item == null);

            // If caption is included, add it to the array
            if (allBindings['has']('optionsCaption')) {
                captionValue = ko.utils.unwrapObservable(allBindings.get('optionsCaption'));
                // If caption value is null or undefined, don't show a caption
                if (captionValue !== null && captionValue !== undefined) {
                    filteredArray.unshift(captionPlaceholder);
                }
            }
        } else {
            // If a falsy value is provided (e.g. null), we'll simply empty the select element
        }

        function applyToObject(object, predicate, defaultValue) {
            var predicateType = typeof predicate;
            if (predicateType == "function")    // Given a function; run it against the data value
                return predicate(object);
            else if (predicateType == "string") // Given a string; treat it as a property name on the data value
                return object[predicate];
            else                                // Given no optionsText arg; use the data value itself
                return defaultValue;
        }

        // The following functions can run at two different times:
        // The first is when the whole array is being updated directly from this binding handler.
        // The second is when an observable value for a specific array entry is updated.
        // oldOptions will be empty in the first case, but will be filled with the previously generated option in the second.
        var itemUpdate = false;
        function optionForArrayItem(arrayEntry, index, oldOptions) {
            if (oldOptions.length) {
                previousSelectedValues = !valueAllowUnset && oldOptions[0].selected ? [ ko.selectExtensions.readValue(oldOptions[0]) ] : [];
                itemUpdate = true;
            }
            var option = element.ownerDocument.createElement("option");
            if (arrayEntry === captionPlaceholder) {
                ko.utils.setTextContent(option, allBindings.get('optionsCaption'));
                ko.selectExtensions.writeValue(option, undefined);
            } else {
                // Apply a value to the option element
                var optionValue = applyToObject(arrayEntry, allBindings.get('optionsValue'), arrayEntry);
                ko.selectExtensions.writeValue(option, ko.utils.unwrapObservable(optionValue));

                // Apply some text to the option element
                var optionText = applyToObject(arrayEntry, allBindings.get('optionsText'), optionValue);
                ko.utils.setTextContent(option, optionText);
            }
            return [option];
        }

        // By using a beforeRemove callback, we delay the removal until after new items are added. This fixes a selection
        // problem in IE<=8 and Firefox. See https://github.com/knockout/knockout/issues/1208
        arrayToDomNodeChildrenOptions['beforeRemove'] = option => element.removeChild(option);

        function setSelectionCallback(arrayEntry, newOptions) {
            if (itemUpdate && valueAllowUnset) {
                // The model value is authoritative, so make sure its value is the one selected
                ko.bindingEvent.notify(element, ko.bindingEvent.childrenComplete);
            } else if (previousSelectedValues.length) {
                // IE6 doesn't like us to assign selection to OPTION nodes before they're added to the document.
                // That's why we first added them without selection. Now it's time to set the selection.
                var isSelected = ko.utils.arrayIndexOf(previousSelectedValues, ko.selectExtensions.readValue(newOptions[0])) >= 0;
                newOptions[0].selected = isSelected;

                // If this option was changed from being selected during a single-item update, notify the change
                if (itemUpdate && !isSelected) {
                    ko.dependencyDetection.ignore(ko.utils.triggerEvent, null, [element, "change"]);
                }
            }
        }

        var callback = setSelectionCallback;
        if (allBindings['has']('optionsAfterRender') && typeof allBindings.get('optionsAfterRender') == "function") {
            callback = (arrayEntry, newOptions) => {
                setSelectionCallback(arrayEntry, newOptions);
                ko.dependencyDetection.ignore(allBindings.get('optionsAfterRender'), null, [newOptions[0], arrayEntry !== captionPlaceholder ? arrayEntry : undefined]);
            }
        }

        ko.utils.setDomNodeChildrenFromArrayMapping(element, filteredArray, optionForArrayItem, arrayToDomNodeChildrenOptions, callback);

        if (!valueAllowUnset) {
            // Determine if the selection has changed as a result of updating the options list
            var selectionChanged;
            if (multiple) {
                // For a multiple-select box, compare the new selection count to the previous one
                // But if nothing was selected before, the selection can't have changed
                selectionChanged = previousSelectedValues.length && selectedOptions().length < previousSelectedValues.length;
            } else {
                // For a single-select box, compare the current value to the previous value
                // But if nothing was selected before or nothing is selected now, just look for a change in selection
                selectionChanged = (previousSelectedValues.length && element.selectedIndex >= 0)
                    ? (ko.selectExtensions.readValue(element.options[element.selectedIndex]) !== previousSelectedValues[0])
                    : (previousSelectedValues.length || element.selectedIndex >= 0);
            }

            // Ensure consistency between model value and selected option.
            // If the dropdown was changed so that selection is no longer the same,
            // notify the value or selectedOptions binding.
            if (selectionChanged) {
                ko.dependencyDetection.ignore(ko.utils.triggerEvent, null, [element, "change"]);
            }
        }

        if (valueAllowUnset || ko.computedContext.isInitial()) {
            ko.bindingEvent.notify(element, ko.bindingEvent.childrenComplete);
        }

        if (previousScrollTop && Math.abs(previousScrollTop - element.scrollTop) > 20)
            element.scrollTop = previousScrollTop;
    }
};
ko.bindingHandlers['options'].optionValueDomDataKey = ko.utils.domData.nextKey();
ko.bindingHandlers['style'] = {
    'update': (element, valueAccessor) => {
        var value = ko.utils.unwrapObservable(valueAccessor() || {});
        ko.utils.objectForEach(value, (styleName, styleValue) => {
            styleValue = ko.utils.unwrapObservable(styleValue);

            if (styleValue === null || styleValue === undefined || styleValue === false) {
                // Empty string removes the value, whereas null/undefined have no effect
                styleValue = "";
            }

            if (/^--/.test(styleName)) {
                // Is styleName a custom CSS property?
                element.style.setProperty(styleName, styleValue);
            } else {
                styleName = styleName.replace(/-(\w)/g, (all, letter) => letter.toUpperCase());

                var previousStyle = element.style[styleName];
                element.style[styleName] = styleValue;

                if (styleValue !== previousStyle && element.style[styleName] == previousStyle && !isNaN(styleValue)) {
                    element.style[styleName] = styleValue + "px";
                }
            }
        });
    }
};
ko.bindingHandlers['submit'] = {
    'init': (element, valueAccessor, allBindings, viewModel, bindingContext) => {
        if (typeof valueAccessor() != "function")
            throw new Error("The value for a submit binding must be a function");
        ko.utils.registerEventHandler(element, "submit", event => {
            var handlerReturnValue;
            var value = valueAccessor();
            try { handlerReturnValue = value.call(bindingContext['$data'], element); }
            finally {
                if (handlerReturnValue !== true) { // Normally we want to prevent default action. Developer can override this be explicitly returning true.
                    if (event.preventDefault)
                        event.preventDefault();
                    else
                        event.returnValue = false;
                }
            }
        });
    }
};
ko.bindingHandlers['text'] = {
    'init': () => {
        // Prevent binding on the dynamically-injected text node (as developers are unlikely to expect that, and it has security implications).
        // It should also make things faster, as we no longer have to consider whether the text node might be bindable.
        return { 'controlsDescendantBindings': true };
    },
    'update': (element, valueAccessor) =>
        ko.utils.setTextContent(element, valueAccessor())
};
ko.virtualElements.allowedBindings['text'] = true;
ko.bindingHandlers['textInput'] = {
    'init': (element, valueAccessor, allBindings) => {

        var previousElementValue = element.value,
            timeoutHandle,
            elementValueBeforeEvent;

        var updateModel = event => {
            clearTimeout(timeoutHandle);
            elementValueBeforeEvent = timeoutHandle = undefined;

            var elementValue = element.value;
            if (previousElementValue !== elementValue) {
                // Provide a way for tests to know exactly which event was processed
                if (DEBUG && event) element['_ko_textInputProcessedEvent'] = event.type;
                previousElementValue = elementValue;
                ko.expressionRewriting.writeValueToProperty(valueAccessor(), allBindings, 'textInput', elementValue);
            }
        };

        var deferUpdateModel = event => {
            if (!timeoutHandle) {
                // The elementValueBeforeEvent variable is set *only* during the brief gap between an
                // event firing and the updateModel function running. This allows us to ignore model
                // updates that are from the previous state of the element, usually due to techniques
                // such as rateLimit. Such updates, if not ignored, can cause keystrokes to be lost.
                elementValueBeforeEvent = element.value;
                var handler = DEBUG ? updateModel.bind(element, {type: event.type}) : updateModel;
                timeoutHandle = ko.utils.setTimeout(handler, 4);
            }
        };

        var updateView = () => {
            var modelValue = ko.utils.unwrapObservable(valueAccessor());

            if (modelValue === null || modelValue === undefined) {
                modelValue = '';
            }

            if (elementValueBeforeEvent !== undefined && modelValue === elementValueBeforeEvent) {
                ko.utils.setTimeout(updateView, 4);
                return;
            }

            // Update the element only if the element and model are different. On some browsers, updating the value
            // will move the cursor to the end of the input, which would be bad while the user is typing.
            if (element.value !== modelValue) {
                element.value = modelValue;
                previousElementValue = element.value; // In case the browser changes the value (see #2281)
            }
        };

        var onEvent = (event, handler) =>
            ko.utils.registerEventHandler(element, event, handler);

        if (DEBUG && ko.bindingHandlers['textInput']['_forceUpdateOn']) {
            // Provide a way for tests to specify exactly which events are bound
            ko.utils.arrayForEach(ko.bindingHandlers['textInput']['_forceUpdateOn'], eventName => {
                if (eventName.slice(0,5) == 'after') {
                    onEvent(eventName.slice(5), deferUpdateModel);
                } else {
                    onEvent(eventName, updateModel);
                }
            });
        } else {
            onEvent('input', updateModel);
        }

        // Bind to the change event so that we can catch programmatic updates of the value that fire this event.
        onEvent('change', updateModel);

        // To deal with browsers that don't notify any kind of event for some changes (IE, Safari, etc.)
        onEvent('blur', updateModel);

        ko.computed(updateView, null, { disposeWhenNodeIsRemoved: element });
    }
};
ko.expressionRewriting.twoWayBindings['textInput'] = true;

// textinput is an alias for textInput
ko.bindingHandlers['textinput'] = {
    // preprocess is the only way to set up a full alias
    'preprocess': (value, name, addBinding) => addBinding('textInput', value)
};
ko.bindingHandlers['value'] = {
    'init': (element, valueAccessor, allBindings) => {
        var tagName = ko.utils.tagNameLower(element),
            isInputElement = tagName == "input";

        // If the value binding is placed on a radio/checkbox, then just pass through to checkedValue and quit
        if (isInputElement && (element.type == "checkbox" || element.type == "radio")) {
            ko.applyBindingAccessorsToNode(element, { 'checkedValue': valueAccessor });
            return;
        }

        var eventsToCatch = [];
        var requestedEventsToCatch = allBindings.get("valueUpdate");
        var elementValueBeforeEvent = null;

        if (requestedEventsToCatch) {
            // Allow both individual event names, and arrays of event names
            if (typeof requestedEventsToCatch == "string") {
                eventsToCatch = [requestedEventsToCatch];
            } else {
                eventsToCatch = requestedEventsToCatch ? requestedEventsToCatch.filter((item, index) =>
                    requestedEventsToCatch.indexOf(item) === index
                ) : [];
            }
            ko.utils.arrayRemoveItem(eventsToCatch, "change");  // We'll subscribe to "change" events later
        }

        var valueUpdateHandler = () => {
            elementValueBeforeEvent = null;
            var modelValue = valueAccessor();
            var elementValue = ko.selectExtensions.readValue(element);
            ko.expressionRewriting.writeValueToProperty(modelValue, allBindings, 'value', elementValue);
        }

        ko.utils.arrayForEach(eventsToCatch, eventName => {
            // The syntax "after<eventname>" means "run the handler asynchronously after the event"
            // This is useful, for example, to catch "keydown" events after the browser has updated the control
            // (otherwise, ko.selectExtensions.readValue(this) will receive the control's value *before* the key event)
            var handler = valueUpdateHandler;
            if (ko.utils.stringStartsWith(eventName, "after")) {
                handler = () => {
                    // The elementValueBeforeEvent variable is non-null *only* during the brief gap between
                    // a keyX event firing and the valueUpdateHandler running, which is scheduled to happen
                    // at the earliest asynchronous opportunity. We store this temporary information so that
                    // if, between keyX and valueUpdateHandler, the underlying model value changes separately,
                    // we can overwrite that model value change with the value the user just typed. Otherwise,
                    // techniques like rateLimit can trigger model changes at critical moments that will
                    // override the user's inputs, causing keystrokes to be lost.
                    elementValueBeforeEvent = ko.selectExtensions.readValue(element);
                    ko.utils.setTimeout(valueUpdateHandler, 0);
                };
                eventName = eventName.substring("after".length);
            }
            ko.utils.registerEventHandler(element, eventName, handler);
        });

        var updateFromModel;

        if (isInputElement && element.type == "file") {
            // For file input elements, can only write the empty string
            updateFromModel = () => {
                var newValue = ko.utils.unwrapObservable(valueAccessor());
                if (newValue === null || newValue === undefined || newValue === "") {
                    element.value = "";
                } else {
                    ko.dependencyDetection.ignore(valueUpdateHandler);  // reset the model to match the element
                }
            }
        } else {
            updateFromModel = () => {
                var newValue = ko.utils.unwrapObservable(valueAccessor());
                var elementValue = ko.selectExtensions.readValue(element);

                if (elementValueBeforeEvent !== null && newValue === elementValueBeforeEvent) {
                    ko.utils.setTimeout(updateFromModel, 0);
                    return;
                }

                var valueHasChanged = newValue !== elementValue;

                if (valueHasChanged || elementValue === undefined) {
                    if (tagName === "select") {
                        var allowUnset = allBindings.get('valueAllowUnset');
                        ko.selectExtensions.writeValue(element, newValue, allowUnset);
                        if (!allowUnset && newValue !== ko.selectExtensions.readValue(element)) {
                            // If you try to set a model value that can't be represented in an already-populated dropdown, reject that change,
                            // because you're not allowed to have a model value that disagrees with a visible UI selection.
                            ko.dependencyDetection.ignore(valueUpdateHandler);
                        }
                    } else {
                        ko.selectExtensions.writeValue(element, newValue);
                    }
                }
            };
        }

        if (tagName === "select") {
            var updateFromModelComputed;
            ko.bindingEvent.subscribe(element, ko.bindingEvent.childrenComplete, () => {
                if (!updateFromModelComputed) {
                    ko.utils.registerEventHandler(element, "change", valueUpdateHandler);
                    updateFromModelComputed = ko.computed(updateFromModel, null, { disposeWhenNodeIsRemoved: element });
                } else if (allBindings.get('valueAllowUnset')) {
                    updateFromModel();
                } else {
                    valueUpdateHandler();
                }
            }, null, { 'notifyImmediately': true });
        } else {
            ko.utils.registerEventHandler(element, "change", valueUpdateHandler);
            ko.computed(updateFromModel, null, { disposeWhenNodeIsRemoved: element });
        }
    },
    'update': () => {} // Keep for backwards compatibility with code that may have wrapped value binding
};
ko.expressionRewriting.twoWayBindings['value'] = true;
ko.bindingHandlers['visible'] = {
    'update': (element, valueAccessor) => {
        var value = ko.utils.unwrapObservable(valueAccessor());
        var isCurrentlyVisible = !(element.style.display == "none");
        if (value && !isCurrentlyVisible)
            element.style.display = "";
        else if (isCurrentlyVisible && !value)
            element.style.display = "none";
    }
};

ko.bindingHandlers['hidden'] = {
    'update': (element, valueAccessor) =>
        element.hidden = !!ko.utils.unwrapObservable(valueAccessor())
};
// 'click' is just a shorthand for the usual full-length event:{click:handler}
makeEventHandlerShortcut('click');
// If you want to make a custom template engine,
//
// [1] Inherit from this class (like ko.nativeTemplateEngine does)
// [2] Override 'renderTemplateSource', supplying a function with this signature:
//
//        function (templateSource, bindingContext, options) {
//            // - templateSource.text() is the text of the template you should render
//            // - bindingContext.$data is the data you should pass into the template
//            //   - you might also want to make bindingContext.$parent, bindingContext.$parents,
//            //     and bindingContext.$root available in the template too
//            // - options gives you access to any other properties set on "data-bind: { template: options }"
//            // - templateDocument is the document object of the template
//            //
//            // Return value: an array of DOM nodes
//        }
//
// [3] Override 'createJavaScriptEvaluatorBlock', supplying a function with this signature:
//
//        function (script) {
//            // Return value: Whatever syntax means "Evaluate the JavaScript statement 'script' and output the result"
//            //               For example, the jquery.tmpl template engine converts 'someScript' to '${ someScript }'
//        }
//
//     This is only necessary if you want to allow data-bind attributes to reference arbitrary template variables.
//     If you don't want to allow that, you can set the property 'allowTemplateRewriting' to false (like ko.nativeTemplateEngine does)
//     and then you don't need to override 'createJavaScriptEvaluatorBlock'.

ko.templateEngine = function () { };

ko.templateEngine.prototype['renderTemplateSource'] = (templateSource, bindingContext, options, templateDocument) => {
    throw new Error("Override renderTemplateSource");
};

ko.templateEngine.prototype['createJavaScriptEvaluatorBlock'] = script => {
    throw new Error("Override createJavaScriptEvaluatorBlock");
};

ko.templateEngine.prototype['makeTemplateSource'] = (template, templateDocument) => {
    // Named template
    if (typeof template == "string") {
        templateDocument = templateDocument || document;
        var elem = templateDocument.getElementById(template);
        if (!elem)
            throw new Error("Cannot find template with ID " + template);
        return new ko.templateSources.domElement(elem);
    } else if ((template.nodeType == 1) || (template.nodeType == 8)) {
        // Anonymous template
        return new ko.templateSources.anonymousTemplate(template);
    } else
        throw new Error("Unknown template type: " + template);
};

ko.templateEngine.prototype['renderTemplate'] = function (template, bindingContext, options, templateDocument) {
    var templateSource = this['makeTemplateSource'](template, templateDocument);
    return this['renderTemplateSource'](templateSource, bindingContext, options, templateDocument);
};

ko.templateEngine.prototype['isTemplateRewritten'] = function (template, templateDocument) {
    // Skip rewriting if requested
    if (this['allowTemplateRewriting'] === false)
        return true;
    return this['makeTemplateSource'](template, templateDocument)['data']("isRewritten");
};

ko.templateEngine.prototype['rewriteTemplate'] = function (template, rewriterCallback, templateDocument) {
    var templateSource = this['makeTemplateSource'](template, templateDocument);
    var rewritten = rewriterCallback(templateSource['text']());
    templateSource['text'](rewritten);
    templateSource['data']("isRewritten", true);
};
(() => {
    // A template source represents a read/write way of accessing a template. This is to eliminate the need for template loading/saving
    // logic to be duplicated in every template engine (and means they can all work with anonymous templates, etc.)
    //
    // Two are provided by default:
    //  1. ko.templateSources.domElement       - reads/writes the text content of an arbitrary DOM element
    //  2. ko.templateSources.anonymousElement - uses ko.utils.domData to read/write text *associated* with the DOM element, but
    //                                           without reading/writing the actual element text content, since it will be overwritten
    //                                           with the rendered template output.
    // You can implement your own template source if you want to fetch/store templates somewhere other than in DOM elements.
    // Template sources need to have the following functions:
    //   text() 			- returns the template text from your storage location
    //   text(value)		- writes the supplied template text to your storage location
    //   data(key)			- reads values stored using data(key, value) - see below
    //   data(key, value)	- associates "value" with this template and the key "key". Is used to store information like "isRewritten".
    //
    // Optionally, template sources can also have the following functions:
    //   nodes()            - returns a DOM element containing the nodes of this template, where available
    //   nodes(value)       - writes the given DOM element to your storage location
    // If a DOM element is available for a given template source, template engines are encouraged to use it in preference over text()
    // for improved speed. However, all templateSources must supply text() even if they don't supply nodes().
    //
    // Once you've implemented a templateSource, make your template engine use it by subclassing whatever template engine you were
    // using and overriding "makeTemplateSource" to return an instance of your custom template source.

    ko.templateSources = {};

    // ---- ko.templateSources.domElement -----

    // template types
    var templateScript = 1,
        templateTextArea = 2,
        templateTemplate = 3,
        templateElement = 4;

    ko.templateSources.domElement = function(element) {
        this.domElement = element;

        if (element) {
            var tagNameLower = ko.utils.tagNameLower(element);
            this.templateType =
                tagNameLower === "script" ? templateScript :
                tagNameLower === "textarea" ? templateTextArea :
                    // For browsers with proper <template> element support, where the .content property gives a document fragment
                tagNameLower == "template" && element.content && element.content.nodeType === 11 ? templateTemplate :
                templateElement;
        }
    }

    ko.templateSources.domElement.prototype['text'] = function(/* valueToWrite */) {
        var elemContentsProperty = this.templateType === templateScript ? "text"
                                 : this.templateType === templateTextArea ? "value"
                                 : "innerHTML";

        if (arguments.length == 0) {
            return this.domElement[elemContentsProperty];
        }
        var valueToWrite = arguments[0];
        if (elemContentsProperty === "innerHTML")
            ko.utils.setHtml(this.domElement, valueToWrite);
        else
            this.domElement[elemContentsProperty] = valueToWrite;
    };

    var dataDomDataPrefix = ko.utils.domData.nextKey() + "_";
    ko.templateSources.domElement.prototype['data'] = function(key /*, valueToWrite */) {
        if (arguments.length === 1) {
            return ko.utils.domData.get(this.domElement, dataDomDataPrefix + key);
        }
        ko.utils.domData.set(this.domElement, dataDomDataPrefix + key, arguments[1]);
    };

    var templatesDomDataKey = ko.utils.domData.nextKey();
    function getTemplateDomData(element) {
        return ko.utils.domData.get(element, templatesDomDataKey) || {};
    }
    function setTemplateDomData(element, data) {
        ko.utils.domData.set(element, templatesDomDataKey, data);
    }

    ko.templateSources.domElement.prototype['nodes'] = function(/* valueToWrite */) {
        var element = this.domElement;
        if (arguments.length == 0) {
            var templateData = getTemplateDomData(element),
                nodes = templateData.containerData || (
                    this.templateType === templateTemplate ? element.content :
                    this.templateType === templateElement ? element :
                    undefined);
            if (!nodes || templateData.alwaysCheckText) {
                // If the template is associated with an element that stores the template as text,
                // parse and cache the nodes whenever there's new text content available. This allows
                // the user to update the template content by updating the text of template node.
                var text = this['text']();
                if (text && text !== templateData.textData) {
                    nodes = ko.utils.parseHtmlForTemplateNodes(text, element.ownerDocument);
                    setTemplateDomData(element, {containerData: nodes, textData: text, alwaysCheckText: true});
                }
            }
            return nodes;
        }
        var valueToWrite = arguments[0];
        if (this.templateType !== undefined) {
            this['text']("");   // clear the text from the node
        }
        setTemplateDomData(element, {containerData: valueToWrite});
    };

    // ---- ko.templateSources.anonymousTemplate -----
    // Anonymous templates are normally saved/retrieved as DOM nodes through "nodes".
    // For compatibility, you can also read "text"; it will be serialized from the nodes on demand.
    // Writing to "text" is still supported, but then the template data will not be available as DOM nodes.

    ko.templateSources.anonymousTemplate = function(element) {
        this.domElement = element;
    };
    ko.templateSources.anonymousTemplate.prototype = new ko.templateSources.domElement();
    ko.templateSources.anonymousTemplate.prototype.constructor = ko.templateSources.anonymousTemplate;
    ko.templateSources.anonymousTemplate.prototype['text'] = function(/* valueToWrite */) {
        if (arguments.length == 0) {
            var templateData = getTemplateDomData(this.domElement);
            if (templateData.textData === undefined && templateData.containerData)
                templateData.textData = templateData.containerData.innerHTML;
            return templateData.textData;
        }
        var valueToWrite = arguments[0];
        setTemplateDomData(this.domElement, {textData: valueToWrite});
    };
})();
(function () {
    var _templateEngine;
    ko.setTemplateEngine = templateEngine => {
        if ((templateEngine != undefined) && !(templateEngine instanceof ko.templateEngine))
            throw new Error("templateEngine must inherit from ko.templateEngine");
        _templateEngine = templateEngine;
    };

    function invokeForEachNodeInContinuousRange(firstNode, lastNode, action) {
        var node, nextInQueue = firstNode, firstOutOfRangeNode = ko.virtualElements.nextSibling(lastNode);
        while (nextInQueue && ((node = nextInQueue) !== firstOutOfRangeNode)) {
            nextInQueue = ko.virtualElements.nextSibling(node);
            action(node, nextInQueue);
        }
    }

    function activateBindingsOnContinuousNodeArray(continuousNodeArray, bindingContext) {
        // To be used on any nodes that have been rendered by a template and have been inserted into some parent element
        // Walks through continuousNodeArray (which *must* be continuous, i.e., an uninterrupted sequence of sibling nodes, because
        // the algorithm for walking them relies on this), and for each top-level item in the virtual-element sense,
        // (1) Does a regular "applyBindings" to associate bindingContext with this node and to activate any non-memoized bindings
        // (2) Unmemoizes any memos in the DOM subtree (e.g., to activate bindings that had been memoized during template rewriting)

        if (continuousNodeArray.length) {
            var firstNode = continuousNodeArray[0],
                lastNode = continuousNodeArray[continuousNodeArray.length - 1],
                parentNode = firstNode.parentNode,
                provider = ko.bindingProvider['instance'],
                preprocessNode = provider['preprocessNode'];

            if (preprocessNode) {
                invokeForEachNodeInContinuousRange(firstNode, lastNode, (node, nextNodeInRange) => {
                    var nodePreviousSibling = node.previousSibling;
                    var newNodes = preprocessNode.call(provider, node);
                    if (newNodes) {
                        if (node === firstNode)
                            firstNode = newNodes[0] || nextNodeInRange;
                        if (node === lastNode)
                            lastNode = newNodes[newNodes.length - 1] || nodePreviousSibling;
                    }
                });

                // Because preprocessNode can change the nodes, including the first and last nodes, update continuousNodeArray to match.
                // We need the full set, including inner nodes, because the unmemoize step might remove the first node (and so the real
                // first node needs to be in the array).
                continuousNodeArray.length = 0;
                if (!firstNode) { // preprocessNode might have removed all the nodes, in which case there's nothing left to do
                    return;
                }
                if (firstNode === lastNode) {
                    continuousNodeArray.push(firstNode);
                } else {
                    continuousNodeArray.push(firstNode, lastNode);
                    ko.utils.fixUpContinuousNodeArray(continuousNodeArray, parentNode);
                }
            }

            // Need to applyBindings *before* unmemoziation, because unmemoization might introduce extra nodes (that we don't want to re-bind)
            // whereas a regular applyBindings won't introduce new memoized nodes
            invokeForEachNodeInContinuousRange(firstNode, lastNode, node => {
                if (node.nodeType === 1 || node.nodeType === 8)
                    ko.applyBindings(bindingContext, node);
            });

            // Make sure any changes done by applyBindings or unmemoize are reflected in the array
            ko.utils.fixUpContinuousNodeArray(continuousNodeArray, parentNode);
        }
    }

    function getFirstNodeFromPossibleArray(nodeOrNodeArray) {
        return nodeOrNodeArray.nodeType ? nodeOrNodeArray
                                        : nodeOrNodeArray.length > 0 ? nodeOrNodeArray[0]
                                        : null;
    }

    function executeTemplate(targetNodeOrNodeArray, renderMode, template, bindingContext, options) {
        options = options || {};
        var firstTargetNode = targetNodeOrNodeArray && getFirstNodeFromPossibleArray(targetNodeOrNodeArray);
        var templateDocument = (firstTargetNode || template || {}).ownerDocument;
        var templateEngineToUse = (options['templateEngine'] || _templateEngine);
        if (!templateEngineToUse['isTemplateRewritten'](template, templateDocument)) {
            templateEngineToUse['rewriteTemplate'](template, htmlString => htmlString, templateDocument);
        }

        var renderedNodesArray = templateEngineToUse['renderTemplate'](template, bindingContext, options, templateDocument);

        // Loosely check result is an array of DOM nodes
        if ((typeof renderedNodesArray.length != "number") || (renderedNodesArray.length > 0 && typeof renderedNodesArray[0].nodeType != "number"))
            throw new Error("Template engine must return an array of DOM nodes");

        var haveAddedNodesToParent = false;
        switch (renderMode) {
            case "replaceChildren":
                ko.virtualElements.setDomNodeChildren(targetNodeOrNodeArray, renderedNodesArray);
                haveAddedNodesToParent = true;
                break;
            case "ignoreTargetNode": break;
            default:
                throw new Error("Unknown renderMode: " + renderMode);
        }

        if (haveAddedNodesToParent) {
            activateBindingsOnContinuousNodeArray(renderedNodesArray, bindingContext);
            if (options['afterRender']) {
                ko.dependencyDetection.ignore(options['afterRender'], null, [renderedNodesArray, bindingContext[options['as'] || '$data']]);
            }
            if (renderMode == "replaceChildren") {
                ko.bindingEvent.notify(targetNodeOrNodeArray, ko.bindingEvent.childrenComplete);
            }
        }

        return renderedNodesArray;
    }

    function resolveTemplateName(template, data, context) {
        // The template can be specified as:
        if (ko.isObservable(template)) {
            // 1. An observable, with string value
            return template();
        }
        // 2. A function of (data, context) returning a string ELSE 3. A string
        return (typeof template === 'function') ? template(data, context) : template;
    }

    ko.renderTemplate = function (template, dataOrBindingContext, options, targetNodeOrNodeArray, renderMode) {
        options = options || {};
        if ((options['templateEngine'] || _templateEngine) == undefined)
            throw new Error("Set a template engine before calling renderTemplate");
        renderMode = renderMode || "replaceChildren";

        if (targetNodeOrNodeArray) {
            var firstTargetNode = getFirstNodeFromPossibleArray(targetNodeOrNodeArray);

            var whenToDispose = () => (!firstTargetNode) || !ko.utils.domNodeIsAttachedToDocument(firstTargetNode); // Passive disposal (on next evaluation)

            return ko.computed( // So the DOM is automatically updated when any dependency changes
                () => {
                    // Ensure we've got a proper binding context to work with
                    var bindingContext = (dataOrBindingContext && (dataOrBindingContext instanceof ko.bindingContext))
                        ? dataOrBindingContext
                        : new ko.bindingContext(dataOrBindingContext, null, null, null, { "exportDependencies": true });

                    var templateName = resolveTemplateName(template, bindingContext['$data'], bindingContext),
                        renderedNodesArray = executeTemplate(targetNodeOrNodeArray, renderMode, templateName, bindingContext, options);
                },
                null,
                { disposeWhen: whenToDispose, disposeWhenNodeIsRemoved: firstTargetNode }
            );
        } else {
            console.log('no targetNodeOrNodeArray');
        }
    };

    ko.renderTemplateForEach = (template, arrayOrObservableArray, options, targetNode, parentBindingContext) => {
        // Since setDomNodeChildrenFromArrayMapping always calls executeTemplateForArrayItem and then
        // activateBindingsCallback for added items, we can store the binding context in the former to use in the latter.
        var arrayItemContext, asName = options['as'];

        // This will be called by setDomNodeChildrenFromArrayMapping to get the nodes to add to targetNode
        var executeTemplateForArrayItem = (arrayValue, index) => {
            // Support selecting template as a function of the data being rendered
            arrayItemContext = parentBindingContext['createChildContext'](arrayValue, {
                'as': asName,
                'noChildContext': options['noChildContext'],
                'extend': context => {
                    context['$index'] = index;
                    if (asName) {
                        context[asName + "Index"] = index;
                    }
                }
            });

            var templateName = resolveTemplateName(template, arrayValue, arrayItemContext);
            return executeTemplate(targetNode, "ignoreTargetNode", templateName, arrayItemContext, options);
        };

        // This will be called whenever setDomNodeChildrenFromArrayMapping has added nodes to targetNode
        var activateBindingsCallback = (arrayValue, addedNodesArray) => {
            activateBindingsOnContinuousNodeArray(addedNodesArray, arrayItemContext);
            if (options['afterRender'])
                options['afterRender'](addedNodesArray, arrayValue);

            // release the "cache" variable, so that it can be collected by
            // the GC when its value isn't used from within the bindings anymore.
            arrayItemContext = null;
        };

        var setDomNodeChildrenFromArrayMapping = function (newArray, changeList) {
            // Call setDomNodeChildrenFromArrayMapping, ignoring any observables unwrapped within (most likely from a callback function).
            // If the array items are observables, though, they will be unwrapped in executeTemplateForArrayItem and managed within setDomNodeChildrenFromArrayMapping.
            ko.dependencyDetection.ignore(ko.utils.setDomNodeChildrenFromArrayMapping, null, [targetNode, newArray, executeTemplateForArrayItem, options, activateBindingsCallback, changeList]);
            ko.bindingEvent.notify(targetNode, ko.bindingEvent.childrenComplete);
        };

        var shouldHideDestroyed = (options['includeDestroyed'] === false);

        if (!shouldHideDestroyed && !options['beforeRemove'] && ko.isObservableArray(arrayOrObservableArray)) {
            setDomNodeChildrenFromArrayMapping(arrayOrObservableArray.peek());

            var subscription = arrayOrObservableArray.subscribe(changeList => {
                setDomNodeChildrenFromArrayMapping(arrayOrObservableArray(), changeList);
            }, null, "arrayChange");
            subscription.disposeWhenNodeIsRemoved(targetNode);

            return subscription;
        } else {
            return ko.computed(() => {
                var unwrappedArray = ko.utils.unwrapObservable(arrayOrObservableArray) || [];
                if (typeof unwrappedArray.length == "undefined") // Coerce single value into array
                    unwrappedArray = [unwrappedArray];

                if (shouldHideDestroyed) {
                    // Filter out any entries marked as destroyed
                    unwrappedArray = unwrappedArray.filter(item => item || item == null);
                }
                setDomNodeChildrenFromArrayMapping(unwrappedArray);

            }, null, { disposeWhenNodeIsRemoved: targetNode });
        }
    };

    var templateComputedDomDataKey = ko.utils.domData.nextKey();
    function disposeOldComputedAndStoreNewOne(element, newComputed) {
        var oldComputed = ko.utils.domData.get(element, templateComputedDomDataKey);
        if (oldComputed && (typeof(oldComputed.dispose) == 'function'))
            oldComputed.dispose();
        ko.utils.domData.set(element, templateComputedDomDataKey, (newComputed && (!newComputed.isActive || newComputed.isActive())) ? newComputed : undefined);
    }

    var cleanContainerDomDataKey = ko.utils.domData.nextKey();
    ko.bindingHandlers['template'] = {
        'init': (element, valueAccessor) => {
            // Support anonymous templates
            var bindingValue = ko.utils.unwrapObservable(valueAccessor());
            if (typeof bindingValue == "string" || 'name' in bindingValue) {
                // It's a named template - clear the element
                ko.virtualElements.emptyNode(element);
            } else if ('nodes' in bindingValue) {
                // We've been given an array of DOM nodes. Save them as the template source.
                // There is no known use case for the node array being an observable array (if the output
                // varies, put that behavior *into* your template - that's what templates are for), and
                // the implementation would be a mess, so assert that it's not observable.
                var nodes = bindingValue['nodes'] || [];
                if (ko.isObservable(nodes)) {
                    throw new Error('The "nodes" option must be a plain, non-observable array.');
                }

                // If the nodes are already attached to a KO-generated container, we reuse that container without moving the
                // elements to a new one (we check only the first node, as the nodes are always moved together)
                let container = nodes[0] && nodes[0].parentNode;
                if (!container || !ko.utils.domData.get(container, cleanContainerDomDataKey)) {
                    container = ko.utils.moveCleanedNodesToContainerElement(nodes);
                    ko.utils.domData.set(container, cleanContainerDomDataKey, true);
                }

                new ko.templateSources.anonymousTemplate(element)['nodes'](container);
            } else {
                // It's an anonymous template - store the element contents, then clear the element
                var templateNodes = ko.virtualElements.childNodes(element);
                if (templateNodes.length > 0) {
                    let container = ko.utils.moveCleanedNodesToContainerElement(templateNodes); // This also removes the nodes from their current parent
                    new ko.templateSources.anonymousTemplate(element)['nodes'](container);
                } else {
                    throw new Error("Anonymous template defined, but no template content was provided");
                }
            }
            return { 'controlsDescendantBindings': true };
        },
        'update': (element, valueAccessor, allBindings, viewModel, bindingContext) => {
            var value = valueAccessor(),
                options = ko.utils.unwrapObservable(value),
                shouldDisplay = true,
                templateComputed = null,
                template;

            if (typeof options == "string") {
                template = value;
                options = {};
            } else {
                template = 'name' in options ? options['name'] : element;

                // Support "if"/"ifnot" conditions
                if ('if' in options)
                    shouldDisplay = ko.utils.unwrapObservable(options['if']);
                if (shouldDisplay && 'ifnot' in options)
                    shouldDisplay = !ko.utils.unwrapObservable(options['ifnot']);

                // Don't show anything if an empty name is given (see #2446)
                if (shouldDisplay && !template) {
                    shouldDisplay = false;
                }
            }

            if ('foreach' in options) {
                // Render once for each data point (treating data set as empty if shouldDisplay==false)
                var dataArray = (shouldDisplay && options['foreach']) || [];
                templateComputed = ko.renderTemplateForEach(template, dataArray, options, element, bindingContext);
            } else if (!shouldDisplay) {
                ko.virtualElements.emptyNode(element);
            } else {
                // Render once for this single data point (or use the viewModel if no data was provided)
                var innerBindingContext = bindingContext;
                if ('data' in options) {
                    innerBindingContext = bindingContext['createChildContext'](options['data'], {
                        'as': options['as'],
                        'noChildContext': options['noChildContext'],
                        'exportDependencies': true
                    });
                }
                templateComputed = ko.renderTemplate(template, innerBindingContext, options, element);
            }

            // It only makes sense to have a single template computed per element (otherwise which one should have its output displayed?)
            disposeOldComputedAndStoreNewOne(element, templateComputed);
        }
    };

    // Anonymous templates can't be rewritten. Give a nice error message if you try to do it.
    ko.expressionRewriting.bindingRewriteValidators['template'] = bindingValue => {
        var parsedBindingValue = ko.expressionRewriting.parseObjectLiteral(bindingValue);

        if ((parsedBindingValue.length == 1) && parsedBindingValue[0]['unknown'])
            return null; // It looks like a string literal, not an object literal, so treat it as a named template (which is allowed for rewriting)

        if (ko.expressionRewriting.keyValueArrayContainsKey(parsedBindingValue, "name"))
            return null; // Named templates can be rewritten, so return "no error"
        return "This template engine does not support anonymous templates nested within its templates";
    };

    ko.virtualElements.allowedBindings['template'] = true;
})();
// Go through the items that have been added and deleted and try to find matches between them.
ko.utils.findMovesInArrayComparison = (left, right, limitFailedCompares) => {
    if (left.length && right.length) {
        var failedCompares, l, r, leftItem, rightItem;
        for (failedCompares = l = 0; (!limitFailedCompares || failedCompares < limitFailedCompares) && (leftItem = left[l]); ++l) {
            for (r = 0; rightItem = right[r]; ++r) {
                if (leftItem['value'] === rightItem['value']) {
                    leftItem['moved'] = rightItem['index'];
                    rightItem['moved'] = leftItem['index'];
                    right.splice(r, 1);         // This item is marked as moved; so remove it from right list
                    failedCompares = r = 0;     // Reset failed compares count because we're checking for consecutive failures
                    break;
                }
            }
            failedCompares += r;
        }
    }
};

ko.utils.compareArrays = (() => {
    var statusNotInOld = 'added', statusNotInNew = 'deleted';

    // Simple calculation based on Levenshtein distance.
    function compareArrays(oldArray, newArray, options) {
        // For backward compatibility, if the third arg is actually a bool, interpret
        // it as the old parameter 'dontLimitMoves'. Newer code should use { dontLimitMoves: true }.
        options = (typeof options === 'boolean') ? { 'dontLimitMoves': options } : (options || {});
        oldArray = oldArray || [];
        newArray = newArray || [];

        if (oldArray.length < newArray.length)
            return compareSmallArrayToBigArray(oldArray, newArray, statusNotInOld, statusNotInNew, options);
        else
            return compareSmallArrayToBigArray(newArray, oldArray, statusNotInNew, statusNotInOld, options);
    }

    function compareSmallArrayToBigArray(smlArray, bigArray, statusNotInSml, statusNotInBig, options) {
        var myMin = Math.min,
            myMax = Math.max,
            editDistanceMatrix = [],
            smlIndex, smlIndexMax = smlArray.length,
            bigIndex, bigIndexMax = bigArray.length,
            compareRange = (bigIndexMax - smlIndexMax) || 1,
            maxDistance = smlIndexMax + bigIndexMax + 1,
            thisRow, lastRow,
            bigIndexMaxForRow, bigIndexMinForRow;

        for (smlIndex = 0; smlIndex <= smlIndexMax; smlIndex++) {
            lastRow = thisRow;
            editDistanceMatrix.push(thisRow = []);
            bigIndexMaxForRow = myMin(bigIndexMax, smlIndex + compareRange);
            bigIndexMinForRow = myMax(0, smlIndex - 1);
            for (bigIndex = bigIndexMinForRow; bigIndex <= bigIndexMaxForRow; bigIndex++) {
                if (!bigIndex)
                    thisRow[bigIndex] = smlIndex + 1;
                else if (!smlIndex)  // Top row - transform empty array into new array via additions
                    thisRow[bigIndex] = bigIndex + 1;
                else if (smlArray[smlIndex - 1] === bigArray[bigIndex - 1])
                    thisRow[bigIndex] = lastRow[bigIndex - 1];                  // copy value (no edit)
                else {
                    var northDistance = lastRow[bigIndex] || maxDistance;       // not in big (deletion)
                    var westDistance = thisRow[bigIndex - 1] || maxDistance;    // not in small (addition)
                    thisRow[bigIndex] = myMin(northDistance, westDistance) + 1;
                }
            }
        }

        var editScript = [], meMinusOne, notInSml = [], notInBig = [];
        for (smlIndex = smlIndexMax, bigIndex = bigIndexMax; smlIndex || bigIndex;) {
            meMinusOne = editDistanceMatrix[smlIndex][bigIndex] - 1;
            if (bigIndex && meMinusOne === editDistanceMatrix[smlIndex][bigIndex-1]) {
                notInSml.push(editScript[editScript.length] = {     // added
                    'status': statusNotInSml,
                    'value': bigArray[--bigIndex],
                    'index': bigIndex });
            } else if (smlIndex && meMinusOne === editDistanceMatrix[smlIndex - 1][bigIndex]) {
                notInBig.push(editScript[editScript.length] = {     // deleted
                    'status': statusNotInBig,
                    'value': smlArray[--smlIndex],
                    'index': smlIndex });
            } else {
                --bigIndex;
                --smlIndex;
                if (!options['sparse']) {
                    editScript.push({
                        'status': "retained",
                        'value': bigArray[bigIndex] });
                }
            }
        }

        // Set a limit on the number of consecutive non-matching comparisons; having it a multiple of
        // smlIndexMax keeps the time complexity of this algorithm linear.
        ko.utils.findMovesInArrayComparison(notInBig, notInSml, !options['dontLimitMoves'] && smlIndexMax * 10);

        return editScript.reverse();
    }

    return compareArrays;
})();
(() => {
    // Objective:
    // * Given an input array, a container DOM node, and a function from array elements to arrays of DOM nodes,
    //   map the array elements to arrays of DOM nodes, concatenate together all these arrays, and use them to populate the container DOM node
    // * Next time we're given the same combination of things (with the array possibly having mutated), update the container DOM node
    //   so that its children is again the concatenation of the mappings of the array elements, but don't re-map any array elements that we
    //   previously mapped - retain those nodes, and just insert/delete other ones

    // "callbackAfterAddingNodes" will be invoked after any "mapping"-generated nodes are inserted into the container node
    // You can use this, for example, to activate bindings on those nodes.

    function mapNodeAndRefreshWhenChanged(containerNode, mapping, valueToMap, callbackAfterAddingNodes, index) {
        // Map this array value inside a dependentObservable so we re-map when any dependency changes
        var mappedNodes = [];
        var dependentObservable = ko.computed(() => {
            var newMappedNodes = mapping(valueToMap, index, ko.utils.fixUpContinuousNodeArray(mappedNodes, containerNode)) || [];

            // On subsequent evaluations, just replace the previously-inserted DOM nodes
            if (mappedNodes.length > 0) {
                var nodesToReplaceArray = mappedNodes.nodeType ? [mappedNodes] : mappedNodes;
                if (nodesToReplaceArray.length > 0) {
                    var insertionPoint = nodesToReplaceArray[0],
                        parent = insertionPoint.parentNode,
                        i, j;
                    for (i = 0, j = newMappedNodes.length; i < j; i++)
                        parent.insertBefore(newMappedNodes[i], insertionPoint);
                    for (i = 0, j = nodesToReplaceArray.length; i < j; i++) {
                        ko.removeNode(nodesToReplaceArray[i]);
                    }
                }
                if (callbackAfterAddingNodes)
                    ko.dependencyDetection.ignore(callbackAfterAddingNodes, null, [valueToMap, newMappedNodes, index]);
            }

            // Replace the contents of the mappedNodes array, thereby updating the record
            // of which nodes would be deleted if valueToMap was itself later removed
            mappedNodes.length = 0;
            ko.utils.arrayPushAll(mappedNodes, newMappedNodes);
        }, null, { disposeWhenNodeIsRemoved: containerNode, disposeWhen: ()=>!!ko.utils.arrayFirst(mappedNodes, ko.utils.domNodeIsAttachedToDocument) });
        return { mappedNodes : mappedNodes, dependentObservable : (dependentObservable.isActive() ? dependentObservable : undefined) };
    }

    var lastMappingResultDomDataKey = ko.utils.domData.nextKey(),
        deletedItemDummyValue = ko.utils.domData.nextKey();

    ko.utils.setDomNodeChildrenFromArrayMapping = (domNode, array, mapping, options, callbackAfterAddingNodes, editScript) => {
        array = array || [];
        if (typeof array.length == "undefined") // Coerce single value into array
            array = [array];

        options = options || {};
        var lastMappingResult = ko.utils.domData.get(domNode, lastMappingResultDomDataKey);
        var isFirstExecution = !lastMappingResult;

        // Build the new mapping result
        var newMappingResult = [];
        var lastMappingResultIndex = 0;
        var currentArrayIndex = 0;

        var nodesToDelete = [];
        var itemsToMoveFirstIndexes = [];
        var itemsForBeforeRemoveCallbacks = [];
        var itemsForMoveCallbacks = [];
        var itemsForAfterAddCallbacks = [];
        var mapData;
        var countWaitingForRemove = 0;

        function itemAdded(value) {
            mapData = { arrayEntry: value, indexObservable: ko.observable(currentArrayIndex++) };
            newMappingResult.push(mapData);
            if (!isFirstExecution) {
                itemsForAfterAddCallbacks.push(mapData);
            }
        }

        function itemMovedOrRetained(oldPosition) {
            mapData = lastMappingResult[oldPosition];
            if (currentArrayIndex !== mapData.indexObservable.peek())
                itemsForMoveCallbacks.push(mapData);
            // Since updating the index might change the nodes, do so before calling fixUpContinuousNodeArray
            mapData.indexObservable(currentArrayIndex++);
            ko.utils.fixUpContinuousNodeArray(mapData.mappedNodes, domNode);
            newMappingResult.push(mapData);
        }

        function callCallback(callback, items) {
            if (callback) {
                for (var i = 0, n = items.length; i < n; i++) {
                    ko.utils.arrayForEach(items[i].mappedNodes, function(node) {
                        callback(node, i, items[i].arrayEntry);
                    });
                }
            }
        }

        if (isFirstExecution) {
            ko.utils.arrayForEach(array, itemAdded);
        } else {
            if (!editScript || (lastMappingResult && lastMappingResult['_countWaitingForRemove'])) {
                // Compare the provided array against the previous one
                var lastArray = Array.prototype.map.call(lastMappingResult, x => x.arrayEntry),
                    compareOptions = {
                        'dontLimitMoves': options['dontLimitMoves'],
                        'sparse': true
                    };
                editScript = ko.utils.compareArrays(lastArray, array, compareOptions);
            }

            for (let i = 0, editScriptItem, movedIndex, itemIndex; editScriptItem = editScript[i]; i++) {
                movedIndex = editScriptItem['moved'];
                itemIndex = editScriptItem['index'];
                switch (editScriptItem['status']) {
                    case "deleted":
                        while (lastMappingResultIndex < itemIndex) {
                            itemMovedOrRetained(lastMappingResultIndex++);
                        }
                        if (movedIndex === undefined) {
                            mapData = lastMappingResult[lastMappingResultIndex];

                            // Stop tracking changes to the mapping for these nodes
                            if (mapData.dependentObservable) {
                                mapData.dependentObservable.dispose();
                                mapData.dependentObservable = undefined;
                            }

                            // Queue these nodes for later removal
                            if (ko.utils.fixUpContinuousNodeArray(mapData.mappedNodes, domNode).length) {
                                if (options['beforeRemove']) {
                                    newMappingResult.push(mapData);
                                    countWaitingForRemove++;
                                    if (mapData.arrayEntry === deletedItemDummyValue) {
                                        mapData = null;
                                    } else {
                                        itemsForBeforeRemoveCallbacks.push(mapData);
                                    }
                                }
                                if (mapData) {
                                    nodesToDelete.push.apply(nodesToDelete, mapData.mappedNodes);
                                }
                            }
                        }
                        lastMappingResultIndex++;
                        break;

                    case "added":
                        while (currentArrayIndex < itemIndex) {
                            itemMovedOrRetained(lastMappingResultIndex++);
                        }
                        if (movedIndex !== undefined) {
                            itemsToMoveFirstIndexes.push(newMappingResult.length);
                            itemMovedOrRetained(movedIndex);
                        } else {
                            itemAdded(editScriptItem['value']);
                        }
                        break;
                }
            }

            while (currentArrayIndex < array.length) {
                itemMovedOrRetained(lastMappingResultIndex++);
            }

            // Record that the current view may still contain deleted items
            // because it means we won't be able to use a provided editScript.
            newMappingResult['_countWaitingForRemove'] = countWaitingForRemove;
        }

        // Store a copy of the array items we just considered so we can difference it next time
        ko.utils.domData.set(domNode, lastMappingResultDomDataKey, newMappingResult);

        // Call beforeMove first before any changes have been made to the DOM
        callCallback(options['beforeMove'], itemsForMoveCallbacks);

        // Next remove nodes for deleted items (or just clean if there's a beforeRemove callback)
        ko.utils.arrayForEach(nodesToDelete, options['beforeRemove'] ? ko.cleanNode : ko.removeNode);

        var i, j, lastNode, nodeToInsert, mappedNodes, activeElement;

        // Since most browsers remove the focus from an element when it's moved to another location,
        // save the focused element and try to restore it later.
        activeElement = domNode.ownerDocument.activeElement;

        // Try to reduce overall moved nodes by first moving the ones that were marked as moved by the edit script
        if (itemsToMoveFirstIndexes.length) {
            while ((i = itemsToMoveFirstIndexes.shift()) != undefined) {
                mapData = newMappingResult[i];
                for (lastNode = undefined; i; ) {
                    if ((mappedNodes = newMappingResult[--i].mappedNodes) && mappedNodes.length) {
                        lastNode = mappedNodes[mappedNodes.length-1];
                        break;
                    }
                }
                for (j = 0; nodeToInsert = mapData.mappedNodes[j]; lastNode = nodeToInsert, j++) {
                    ko.virtualElements.insertAfter(domNode, nodeToInsert, lastNode);
                }
            }
        }

        // Next add/reorder the remaining items (will include deleted items if there's a beforeRemove callback)
        for (i = 0; mapData = newMappingResult[i]; i++) {
            // Get nodes for newly added items
            if (!mapData.mappedNodes)
                ko.utils.extend(mapData, mapNodeAndRefreshWhenChanged(domNode, mapping, mapData.arrayEntry, callbackAfterAddingNodes, mapData.indexObservable));

            // Put nodes in the right place if they aren't there already
            for (j = 0; nodeToInsert = mapData.mappedNodes[j]; lastNode = nodeToInsert, j++) {
                ko.virtualElements.insertAfter(domNode, nodeToInsert, lastNode);
            }

            // Run the callbacks for newly added nodes (for example, to apply bindings, etc.)
            if (!mapData.initialized && callbackAfterAddingNodes) {
                callbackAfterAddingNodes(mapData.arrayEntry, mapData.mappedNodes, mapData.indexObservable);
                mapData.initialized = true;
                lastNode = mapData.mappedNodes[mapData.mappedNodes.length - 1];     // get the last node again since it may have been changed by a preprocessor
            }
        }

        // Restore the focused element if it had lost focus
        if (activeElement && domNode.ownerDocument.activeElement != activeElement) {
            activeElement.focus();
        }

        // If there's a beforeRemove callback, call it after reordering.
        // Note that we assume that the beforeRemove callback will usually be used to remove the nodes using
        // some sort of animation, which is why we first reorder the nodes that will be removed. If the
        // callback instead removes the nodes right away, it would be more efficient to skip reordering them.
        // Perhaps we'll make that change in the future if this scenario becomes more common.
        callCallback(options['beforeRemove'], itemsForBeforeRemoveCallbacks);

        // Replace the stored values of deleted items with a dummy value. This provides two benefits: it marks this item
        // as already "removed" so we won't call beforeRemove for it again, and it ensures that the item won't match up
        // with an actual item in the array and appear as "retained" or "moved".
        for (i = 0; i < itemsForBeforeRemoveCallbacks.length; ++i) {
            itemsForBeforeRemoveCallbacks[i].arrayEntry = deletedItemDummyValue;
        }

        // Finally call afterMove and afterAdd callbacks
        callCallback(options['afterMove'], itemsForMoveCallbacks);
        callCallback(options['afterAdd'], itemsForAfterAddCallbacks);
    }
})();
ko.nativeTemplateEngine = function () {
    this['allowTemplateRewriting'] = false;
}

ko.nativeTemplateEngine.prototype = new ko.templateEngine();
ko.nativeTemplateEngine.prototype.constructor = ko.nativeTemplateEngine;
ko.nativeTemplateEngine.prototype['renderTemplateSource'] = (templateSource, bindingContext, options, templateDocument) => {
    var templateNodesFunc = templateSource.nodes,
        templateNodes = templateNodesFunc ? templateSource.nodes() : null;
    if (templateNodes) {
        return ko.utils.makeArray(templateNodes.cloneNode(true).childNodes);
    }
    var templateText = templateSource['text']();
    return ko.utils.parseHtmlFragment(templateText, templateDocument);
};

ko.nativeTemplateEngine.instance = new ko.nativeTemplateEngine();
ko.setTemplateEngine(ko.nativeTemplateEngine.instance);
	window['ko'] = koExports;
})(this);
})();