Version 3.18.1
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File: event/js/synthetic.js

            /**
             * Define new DOM events that can be subscribed to from Nodes.
             *
             * @module event
             * @submodule event-synthetic
             */
            var CustomEvent = Y.CustomEvent,
                DOMMap   = Y.Env.evt.dom_map,
                toArray  = Y.Array,
                YLang    = Y.Lang,
                isObject = YLang.isObject,
                isString = YLang.isString,
                isArray  = YLang.isArray,
                query    = Y.Selector.query,
                noop     = function () {};
            
            /**
             * <p>The triggering mechanism used by SyntheticEvents.</p>
             *
             * <p>Implementers should not instantiate these directly.  Use the Notifier
             * provided to the event's implemented <code>on(node, sub, notifier)</code> or
             * <code>delegate(node, sub, notifier, filter)</code> methods.</p>
             *
             * @class SyntheticEvent.Notifier
             * @constructor
             * @param handle {EventHandle} the detach handle for the subscription to an
             *              internal custom event used to execute the callback passed to
             *              on(..) or delegate(..)
             * @param emitFacade {Boolean} take steps to ensure the first arg received by
             *              the subscription callback is an event facade
             * @private
             * @since 3.2.0
             */
            function Notifier(handle, emitFacade) {
                this.handle     = handle;
                this.emitFacade = emitFacade;
            }
            
            /**
             * <p>Executes the subscription callback, passing the firing arguments as the
             * first parameters to that callback. For events that are configured with
             * emitFacade=true, it is common practice to pass the triggering DOMEventFacade
             * as the first parameter.  Barring a proper DOMEventFacade or EventFacade
             * (from a CustomEvent), a new EventFacade will be generated.  In that case, if
             * fire() is called with a simple object, it will be mixed into the facade.
             * Otherwise, the facade will be prepended to the callback parameters.</p>
             *
             * <p>For notifiers provided to delegate logic, the first argument should be an
             * object with a &quot;currentTarget&quot; property to identify what object to
             * default as 'this' in the callback.  Typically this is gleaned from the
             * DOMEventFacade or EventFacade, but if configured with emitFacade=false, an
             * object must be provided.  In that case, the object will be removed from the
             * callback parameters.</p>
             *
             * <p>Additional arguments passed during event subscription will be
             * automatically added after those passed to fire().</p>
             *
             * @method fire
             * @param {EventFacade|DOMEventFacade|any} e (see description)
             * @param {any[]} [arg*] additional arguments received by all subscriptions
             * @private
             */
            Notifier.prototype.fire = function (e) {
                // first arg to delegate notifier should be an object with currentTarget
                var args     = toArray(arguments, 0, true),
                    handle   = this.handle,
                    ce       = handle.evt,
                    sub      = handle.sub,
                    thisObj  = sub.context,
                    delegate = sub.filter,
                    event    = e || {},
                    ret;
            
                if (this.emitFacade) {
                    if (!e || !e.preventDefault) {
                        event = ce._getFacade();
            
                        if (isObject(e) && !e.preventDefault) {
                            Y.mix(event, e, true);
                            args[0] = event;
                        } else {
                            args.unshift(event);
                        }
                    }
            
                    event.type    = ce.type;
                    event.details = args.slice();
            
                    if (delegate) {
                        event.container = ce.host;
                    }
                } else if (delegate && isObject(e) && e.currentTarget) {
                    args.shift();
                }
            
                sub.context = thisObj || event.currentTarget || ce.host;
                ret = ce.fire.apply(ce, args);
            
                // have to handle preventedFn and stoppedFn manually because
                // Notifier CustomEvents are forced to emitFacade=false
                if (e.prevented && ce.preventedFn) {
                    ce.preventedFn.apply(ce, args);
                }
            
                if (e.stopped && ce.stoppedFn) {
                    ce.stoppedFn.apply(ce, args);
                }
            
                sub.context = thisObj; // reset for future firing
            
                // to capture callbacks that return false to stopPropagation.
                // Useful for delegate implementations
                return ret;
            };
            
            /**
             * Manager object for synthetic event subscriptions to aggregate multiple synths on the
             * same node without colliding with actual DOM subscription entries in the global map of
             * DOM subscriptions.  Also facilitates proper cleanup on page unload.
             *
             * @class SynthRegistry
             * @constructor
             * @param el {HTMLElement} the DOM element
             * @param yuid {String} the yuid stamp for the element
             * @param key {String} the generated id token used to identify an event type +
             *                     element in the global DOM subscription map.
             * @private
             */
            function SynthRegistry(el, yuid, key) {
                this.handles = [];
                this.el      = el;
                this.key     = key;
                this.domkey  = yuid;
            }
            
            SynthRegistry.prototype = {
                constructor: SynthRegistry,
            
                // A few object properties to fake the CustomEvent interface for page
                // unload cleanup.  DON'T TOUCH!
                type      : '_synth',
                fn        : noop,
                capture   : false,
            
                /**
                 * Adds a subscription from the Notifier registry.
                 *
                 * @method register
                 * @param handle {EventHandle} the subscription
                 * @since 3.4.0
                 */
                register: function (handle) {
                    handle.evt.registry = this;
                    this.handles.push(handle);
                },
            
                /**
                 * Removes the subscription from the Notifier registry.
                 *
                 * @method _unregisterSub
                 * @param sub {Subscription} the subscription
                 * @since 3.4.0
                 */
                unregister: function (sub) {
                    var handles = this.handles,
                        events = DOMMap[this.domkey],
                        i;
            
                    for (i = handles.length - 1; i >= 0; --i) {
                        if (handles[i].sub === sub) {
                            handles.splice(i, 1);
                            break;
                        }
                    }
            
                    // Clean up left over objects when there are no more subscribers.
                    if (!handles.length) {
                        delete events[this.key];
                        if (!Y.Object.size(events)) {
                            delete DOMMap[this.domkey];
                        }
                    }
                },
            
                /**
                 * Used by the event system's unload cleanup process.  When navigating
                 * away from the page, the event system iterates the global map of element
                 * subscriptions and detaches everything using detachAll().  Normally,
                 * the map is populated with custom events, so this object needs to
                 * at least support the detachAll method to duck type its way to
                 * cleanliness.
                 *
                 * @method detachAll
                 * @private
                 * @since 3.4.0
                 */
                detachAll : function () {
                    var handles = this.handles,
                        i = handles.length;
            
                    while (--i >= 0) {
                        handles[i].detach();
                    }
                }
            };
            
            /**
             * <p>Wrapper class for the integration of new events into the YUI event
             * infrastructure.  Don't instantiate this object directly, use
             * <code>Y.Event.define(type, config)</code>.  See that method for details.</p>
             *
             * <p>Properties that MAY or SHOULD be specified in the configuration are noted
             * below and in the description of <code>Y.Event.define</code>.</p>
             *
             * @class SyntheticEvent
             * @constructor
             * @param cfg {Object} Implementation pieces and configuration
             * @since 3.1.0
             * @in event-synthetic
             */
            function SyntheticEvent() {
                this._init.apply(this, arguments);
            }
            
            Y.mix(SyntheticEvent, {
                Notifier: Notifier,
                SynthRegistry: SynthRegistry,
            
                /**
                 * Returns the array of subscription handles for a node for the given event
                 * type.  Passing true as the third argument will create a registry entry
                 * in the event system's DOM map to host the array if one doesn't yet exist.
                 *
                 * @method getRegistry
                 * @param node {Node} the node
                 * @param type {String} the event
                 * @param create {Boolean} create a registration entry to host a new array
                 *                  if one doesn't exist.
                 * @return {Array}
                 * @static
                 * @protected
                 * @since 3.2.0
                 */
                getRegistry: function (node, type, create) {
                    var el     = node._node,
                        yuid   = Y.stamp(el),
                        key    = 'event:' + yuid + type + '_synth',
                        events = DOMMap[yuid];
            
                    if (create) {
                        if (!events) {
                            events = DOMMap[yuid] = {};
                        }
                        if (!events[key]) {
                            events[key] = new SynthRegistry(el, yuid, key);
                        }
                    }
            
                    return (events && events[key]) || null;
                },
            
                /**
                 * Alternate <code>_delete()</code> method for the CustomEvent object
                 * created to manage SyntheticEvent subscriptions.
                 *
                 * @method _deleteSub
                 * @param sub {Subscription} the subscription to clean up
                 * @private
                 * @since 3.2.0
                 */
                _deleteSub: function (sub) {
                    if (sub && sub.fn) {
                        var synth = this.eventDef,
                            method = (sub.filter) ? 'detachDelegate' : 'detach';
            
                        this._subscribers = [];
            
                        if (CustomEvent.keepDeprecatedSubs) {
                            this.subscribers = {};
                        }
            
                        synth[method](sub.node, sub, this.notifier, sub.filter);
                        this.registry.unregister(sub);
            
                        delete sub.fn;
                        delete sub.node;
                        delete sub.context;
                    }
                },
            
                prototype: {
                    constructor: SyntheticEvent,
            
                    /**
                     * Construction logic for the event.
                     *
                     * @method _init
                     * @protected
                     */
                    _init: function () {
                        var config = this.publishConfig || (this.publishConfig = {});
            
                        // The notification mechanism handles facade creation
                        this.emitFacade = ('emitFacade' in config) ?
                                            config.emitFacade :
                                            true;
                        config.emitFacade  = false;
                    },
            
                    /**
                     * <p>Implementers MAY provide this method definition.</p>
                     *
                     * <p>Implement this function if the event supports a different
                     * subscription signature.  This function is used by both
                     * <code>on()</code> and <code>delegate()</code>.  The second parameter
                     * indicates that the event is being subscribed via
                     * <code>delegate()</code>.</p>
                     *
                     * <p>Implementations must remove extra arguments from the args list
                     * before returning.  The required args for <code>on()</code>
                     * subscriptions are</p>
                     * <pre><code>[type, callback, target, context, argN...]</code></pre>
                     *
                     * <p>The required args for <code>delegate()</code>
                     * subscriptions are</p>
                     *
                     * <pre><code>[type, callback, target, filter, context, argN...]</code></pre>
                     *
                     * <p>The return value from this function will be stored on the
                     * subscription in the '_extra' property for reference elsewhere.</p>
                     *
                     * @method processArgs
                     * @param args {Array} parmeters passed to Y.on(..) or Y.delegate(..)
                     * @param delegate {Boolean} true if the subscription is from Y.delegate
                     * @return {any}
                     */
                    processArgs: noop,
            
                    /**
                     * <p>Implementers MAY override this property.</p>
                     *
                     * <p>Whether to prevent multiple subscriptions to this event that are
                     * classified as being the same.  By default, this means the subscribed
                     * callback is the same function.  See the <code>subMatch</code>
                     * method.  Setting this to true will impact performance for high volume
                     * events.</p>
                     *
                     * @property preventDups
                     * @type {Boolean}
                     * @default false
                     */
                    //preventDups  : false,
            
                    /**
                     * <p>Implementers SHOULD provide this method definition.</p>
                     *
                     * Implementation logic for subscriptions done via <code>node.on(type,
                     * fn)</code> or <code>Y.on(type, fn, target)</code>.  This
                     * function should set up the monitor(s) that will eventually fire the
                     * event.  Typically this involves subscribing to at least one DOM
                     * event.  It is recommended to store detach handles from any DOM
                     * subscriptions to make for easy cleanup in the <code>detach</code>
                     * method.  Typically these handles are added to the <code>sub</code>
                     * object.  Also for SyntheticEvents that leverage a single DOM
                     * subscription under the hood, it is recommended to pass the DOM event
                     * object to <code>notifier.fire(e)</code>.  (The event name on the
                     * object will be updated).
                     *
                     * @method on
                     * @param node {Node} the node the subscription is being applied to
                     * @param sub {Subscription} the object to track this subscription
                     * @param notifier {SyntheticEvent.Notifier} call notifier.fire(..) to
                     *              trigger the execution of the subscribers
                     */
                    on: noop,
            
                    /**
                     * <p>Implementers SHOULD provide this method definition.</p>
                     *
                     * <p>Implementation logic for detaching subscriptions done via
                     * <code>node.on(type, fn)</code>.  This function should clean up any
                     * subscriptions made in the <code>on()</code> phase.</p>
                     *
                     * @method detach
                     * @param node {Node} the node the subscription was applied to
                     * @param sub {Subscription} the object tracking this subscription
                     * @param notifier {SyntheticEvent.Notifier} the Notifier used to
                     *              trigger the execution of the subscribers
                     */
                    detach: noop,
            
                    /**
                     * <p>Implementers SHOULD provide this method definition.</p>
                     *
                     * <p>Implementation logic for subscriptions done via
                     * <code>node.delegate(type, fn, filter)</code> or
                     * <code>Y.delegate(type, fn, container, filter)</code>.  Like with
                     * <code>on()</code> above, this function should monitor the environment
                     * for the event being fired, and trigger subscription execution by
                     * calling <code>notifier.fire(e)</code>.</p>
                     *
                     * <p>This function receives a fourth argument, which is the filter
                     * used to identify which Node's are of interest to the subscription.
                     * The filter will be either a boolean function that accepts a target
                     * Node for each hierarchy level as the event bubbles, or a selector
                     * string.  To translate selector strings into filter functions, use
                     * <code>Y.delegate.compileFilter(filter)</code>.</p>
                     *
                     * @method delegate
                     * @param node {Node} the node the subscription is being applied to
                     * @param sub {Subscription} the object to track this subscription
                     * @param notifier {SyntheticEvent.Notifier} call notifier.fire(..) to
                     *              trigger the execution of the subscribers
                     * @param filter {String|Function} Selector string or function that
                     *              accepts an event object and returns null, a Node, or an
                     *              array of Nodes matching the criteria for processing.
                     * @since 3.2.0
                     */
                    delegate       : noop,
            
                    /**
                     * <p>Implementers SHOULD provide this method definition.</p>
                     *
                     * <p>Implementation logic for detaching subscriptions done via
                     * <code>node.delegate(type, fn, filter)</code> or
                     * <code>Y.delegate(type, fn, container, filter)</code>.  This function
                     * should clean up any subscriptions made in the
                     * <code>delegate()</code> phase.</p>
                     *
                     * @method detachDelegate
                     * @param node {Node} the node the subscription was applied to
                     * @param sub {Subscription} the object tracking this subscription
                     * @param notifier {SyntheticEvent.Notifier} the Notifier used to
                     *              trigger the execution of the subscribers
                     * @param filter {String|Function} Selector string or function that
                     *              accepts an event object and returns null, a Node, or an
                     *              array of Nodes matching the criteria for processing.
                     * @since 3.2.0
                     */
                    detachDelegate : noop,
            
                    /**
                     * Sets up the boilerplate for detaching the event and facilitating the
                     * execution of subscriber callbacks.
                     *
                     * @method _on
                     * @param args {Array} array of arguments passed to
                     *              <code>Y.on(...)</code> or <code>Y.delegate(...)</code>
                     * @param delegate {Boolean} true if called from
                     * <code>Y.delegate(...)</code>
                     * @return {EventHandle} the detach handle for this subscription
                     * @private
                     * since 3.2.0
                     */
                    _on: function (args, delegate) {
                        var handles  = [],
                            originalArgs = args.slice(),
                            extra    = this.processArgs(args, delegate),
                            selector = args[2],
                            method   = delegate ? 'delegate' : 'on',
                            nodes, handle;
            
                        // Can't just use Y.all because it doesn't support window (yet?)
                        nodes = (isString(selector)) ?
                            query(selector) :
                            toArray(selector || Y.one(Y.config.win));
            
                        if (!nodes.length && isString(selector)) {
                            handle = Y.on('available', function () {
                                Y.mix(handle, Y[method].apply(Y, originalArgs), true);
                            }, selector);
            
                            return handle;
                        }
            
                        Y.Array.each(nodes, function (node) {
                            var subArgs = args.slice(),
                                filter;
            
                            node = Y.one(node);
            
                            if (node) {
                                if (delegate) {
                                    filter = subArgs.splice(3, 1)[0];
                                }
            
                                // (type, fn, el, thisObj, ...) => (fn, thisObj, ...)
                                subArgs.splice(0, 4, subArgs[1], subArgs[3]);
            
                                if (!this.preventDups ||
                                    !this.getSubs(node, args, null, true))
                                {
                                    handles.push(this._subscribe(node, method, subArgs, extra, filter));
                                }
                            }
                        }, this);
            
                        return (handles.length === 1) ?
                            handles[0] :
                            new Y.EventHandle(handles);
                    },
            
                    /**
                     * Creates a new Notifier object for use by this event's
                     * <code>on(...)</code> or <code>delegate(...)</code> implementation
                     * and register the custom event proxy in the DOM system for cleanup.
                     *
                     * @method _subscribe
                     * @param node {Node} the Node hosting the event
                     * @param method {String} "on" or "delegate"
                     * @param args {Array} the subscription arguments passed to either
                     *              <code>Y.on(...)</code> or <code>Y.delegate(...)</code>
                     *              after running through <code>processArgs(args)</code> to
                     *              normalize the argument signature
                     * @param extra {any} Extra data parsed from
                     *              <code>processArgs(args)</code>
                     * @param filter {String|Function} the selector string or function
                     *              filter passed to <code>Y.delegate(...)</code> (not
                     *              present when called from <code>Y.on(...)</code>)
                     * @return {EventHandle}
                     * @private
                     * @since 3.2.0
                     */
                    _subscribe: function (node, method, args, extra, filter) {
                        var dispatcher = new Y.CustomEvent(this.type, this.publishConfig),
                            handle     = dispatcher.on.apply(dispatcher, args),
                            notifier   = new Notifier(handle, this.emitFacade),
                            registry   = SyntheticEvent.getRegistry(node, this.type, true),
                            sub        = handle.sub;
            
                        sub.node   = node;
                        sub.filter = filter;
                        if (extra) {
                            this.applyArgExtras(extra, sub);
                        }
            
                        Y.mix(dispatcher, {
                            eventDef     : this,
                            notifier     : notifier,
                            host         : node,       // I forget what this is for
                            currentTarget: node,       // for generating facades
                            target       : node,       // for generating facades
                            el           : node._node, // For category detach
            
                            _delete      : SyntheticEvent._deleteSub
                        }, true);
            
                        handle.notifier = notifier;
            
                        registry.register(handle);
            
                        // Call the implementation's "on" or "delegate" method
                        this[method](node, sub, notifier, filter);
            
                        return handle;
                    },
            
                    /**
                     * <p>Implementers MAY provide this method definition.</p>
                     *
                     * <p>Implement this function if you want extra data extracted during
                     * processArgs to be propagated to subscriptions on a per-node basis.
                     * That is to say, if you call <code>Y.on('xyz', fn, xtra, 'div')</code>
                     * the data returned from processArgs will be shared
                     * across the subscription objects for all the divs.  If you want each
                     * subscription to receive unique information, do that processing
                     * here.</p>
                     *
                     * <p>The default implementation adds the data extracted by processArgs
                     * to the subscription object as <code>sub._extra</code>.</p>
                     *
                     * @method applyArgExtras
                     * @param extra {any} Any extra data extracted from processArgs
                     * @param sub {Subscription} the individual subscription
                     */
                    applyArgExtras: function (extra, sub) {
                        sub._extra = extra;
                    },
            
                    /**
                     * Removes the subscription(s) from the internal subscription dispatch
                     * mechanism.  See <code>SyntheticEvent._deleteSub</code>.
                     *
                     * @method _detach
                     * @param args {Array} The arguments passed to
                     *                  <code>node.detach(...)</code>
                     * @private
                     * @since 3.2.0
                     */
                    _detach: function (args) {
                        // Can't use Y.all because it doesn't support window (yet?)
                        // TODO: Does Y.all support window now?
                        var target = args[2],
                            els    = (isString(target)) ?
                                        query(target) : toArray(target),
                            node, i, len, handles, j;
            
                        // (type, fn, el, context, filter?) => (type, fn, context, filter?)
                        args.splice(2, 1);
            
                        for (i = 0, len = els.length; i < len; ++i) {
                            node = Y.one(els[i]);
            
                            if (node) {
                                handles = this.getSubs(node, args);
            
                                if (handles) {
                                    for (j = handles.length - 1; j >= 0; --j) {
                                        handles[j].detach();
                                    }
                                }
                            }
                        }
                    },
            
                    /**
                     * Returns the detach handles of subscriptions on a node that satisfy a
                     * search/filter function.  By default, the filter used is the
                     * <code>subMatch</code> method.
                     *
                     * @method getSubs
                     * @param node {Node} the node hosting the event
                     * @param args {Array} the array of original subscription args passed
                     *              to <code>Y.on(...)</code> (before
                     *              <code>processArgs</code>
                     * @param filter {Function} function used to identify a subscription
                     *              for inclusion in the returned array
                     * @param first {Boolean} stop after the first match (used to check for
                     *              duplicate subscriptions)
                     * @return {EventHandle[]} detach handles for the matching subscriptions
                     */
                    getSubs: function (node, args, filter, first) {
                        var registry = SyntheticEvent.getRegistry(node, this.type),
                            handles  = [],
                            allHandles, i, len, handle;
            
                        if (registry) {
                            allHandles = registry.handles;
            
                            if (!filter) {
                                filter = this.subMatch;
                            }
            
                            for (i = 0, len = allHandles.length; i < len; ++i) {
                                handle = allHandles[i];
                                if (filter.call(this, handle.sub, args)) {
                                    if (first) {
                                        return handle;
                                    } else {
                                        handles.push(allHandles[i]);
                                    }
                                }
                            }
                        }
            
                        return handles.length && handles;
                    },
            
                    /**
                     * <p>Implementers MAY override this to define what constitutes a
                     * &quot;same&quot; subscription.  Override implementations should
                     * consider the lack of a comparator as a match, so calling
                     * <code>getSubs()</code> with no arguments will return all subs.</p>
                     *
                     * <p>Compares a set of subscription arguments against a Subscription
                     * object to determine if they match.  The default implementation
                     * compares the callback function against the second argument passed to
                     * <code>Y.on(...)</code> or <code>node.detach(...)</code> etc.</p>
                     *
                     * @method subMatch
                     * @param sub {Subscription} the existing subscription
                     * @param args {Array} the calling arguments passed to
                     *                  <code>Y.on(...)</code> etc.
                     * @return {Boolean} true if the sub can be described by the args
                     *                  present
                     * @since 3.2.0
                     */
                    subMatch: function (sub, args) {
                        // Default detach cares only about the callback matching
                        return !args[1] || sub.fn === args[1];
                    }
                }
            }, true);
            
            Y.SyntheticEvent = SyntheticEvent;
            
            /**
             * <p>Defines a new event in the DOM event system.  Implementers are
             * responsible for monitoring for a scenario whereby the event is fired.  A
             * notifier object is provided to the functions identified below.  When the
             * criteria defining the event are met, call notifier.fire( [args] ); to
             * execute event subscribers.</p>
             *
             * <p>The first parameter is the name of the event.  The second parameter is a
             * configuration object which define the behavior of the event system when the
             * new event is subscribed to or detached from.  The methods that should be
             * defined in this configuration object are <code>on</code>,
             * <code>detach</code>, <code>delegate</code>, and <code>detachDelegate</code>.
             * You are free to define any other methods or properties needed to define your
             * event.  Be aware, however, that since the object is used to subclass
             * SyntheticEvent, you should avoid method names used by SyntheticEvent unless
             * your intention is to override the default behavior.</p>
             *
             * <p>This is a list of properties and methods that you can or should specify
             * in the configuration object:</p>
             *
             * <dl>
             *   <dt><code>on</code></dt>
             *       <dd><code>function (node, subscription, notifier)</code> The
             *       implementation logic for subscription.  Any special setup you need to
             *       do to create the environment for the event being fired--E.g. native
             *       DOM event subscriptions.  Store subscription related objects and
             *       state on the <code>subscription</code> object.  When the
             *       criteria have been met to fire the synthetic event, call
             *       <code>notifier.fire(e)</code>.  See Notifier's <code>fire()</code>
             *       method for details about what to pass as parameters.</dd>
             *
             *   <dt><code>detach</code></dt>
             *       <dd><code>function (node, subscription, notifier)</code> The
             *       implementation logic for cleaning up a detached subscription. E.g.
             *       detach any DOM subscriptions added in <code>on</code>.</dd>
             *
             *   <dt><code>delegate</code></dt>
             *       <dd><code>function (node, subscription, notifier, filter)</code> The
             *       implementation logic for subscription via <code>Y.delegate</code> or
             *       <code>node.delegate</code>.  The filter is typically either a selector
             *       string or a function.  You can use
             *       <code>Y.delegate.compileFilter(selectorString)</code> to create a
             *       filter function from a selector string if needed.  The filter function
             *       expects an event object as input and should output either null, a
             *       matching Node, or an array of matching Nodes.  Otherwise, this acts
             *       like <code>on</code> DOM event subscriptions.  Store subscription
             *       related objects and information on the <code>subscription</code>
             *       object.  When the criteria have been met to fire the synthetic event,
             *       call <code>notifier.fire(e)</code> as noted above.</dd>
             *
             *   <dt><code>detachDelegate</code></dt>
             *       <dd><code>function (node, subscription, notifier)</code> The
             *       implementation logic for cleaning up a detached delegate subscription.
             *       E.g. detach any DOM delegate subscriptions added in
             *       <code>delegate</code>.</dd>
             *
             *   <dt><code>publishConfig</code></dt>
             *       <dd>(Object) The configuration object that will be used to instantiate
             *       the underlying CustomEvent. See Notifier's <code>fire</code> method
             *       for details.</dd>
             *
             *   <dt><code>processArgs</code></dt
             *       <dd>
             *          <p><code>function (argArray, fromDelegate)</code> Optional method
             *          to extract any additional arguments from the subscription
             *          signature.  Using this allows <code>on</code> or
             *          <code>delegate</code> signatures like
             *          <code>node.on(&quot;hover&quot;, overCallback,
             *          outCallback)</code>.</p>
             *          <p>When processing an atypical argument signature, make sure the
             *          args array is returned to the normal signature before returning
             *          from the function.  For example, in the &quot;hover&quot; example
             *          above, the <code>outCallback</code> needs to be <code>splice</code>d
             *          out of the array.  The expected signature of the args array for
             *          <code>on()</code> subscriptions is:</p>
             *          <pre>
             *              <code>[type, callback, target, contextOverride, argN...]</code>
             *          </pre>
             *          <p>And for <code>delegate()</code>:</p>
             *          <pre>
             *              <code>[type, callback, target, filter, contextOverride, argN...]</code>
             *          </pre>
             *          <p>where <code>target</code> is the node the event is being
             *          subscribed for.  You can see these signatures documented for
             *          <code>Y.on()</code> and <code>Y.delegate()</code> respectively.</p>
             *          <p>Whatever gets returned from the function will be stored on the
             *          <code>subscription</code> object under
             *          <code>subscription._extra</code>.</p></dd>
             *   <dt><code>subMatch</code></dt>
             *       <dd>
             *           <p><code>function (sub, args)</code>  Compares a set of
             *           subscription arguments against a Subscription object to determine
             *           if they match.  The default implementation compares the callback
             *           function against the second argument passed to
             *           <code>Y.on(...)</code> or <code>node.detach(...)</code> etc.</p>
             *       </dd>
             * </dl>
             *
             * @method define
             * @param type {String} the name of the event
             * @param config {Object} the prototype definition for the new event (see above)
             * @param force {Boolean} override an existing event (use with caution)
             * @return {SyntheticEvent} the subclass implementation instance created to
             *              handle event subscriptions of this type
             * @static
             * @for Event
             * @since 3.1.0
             * @in event-synthetic
             */
            Y.Event.define = function (type, config, force) {
                var eventDef, Impl, synth;
            
                if (type && type.type) {
                    eventDef = type;
                    force = config;
                } else if (config) {
                    eventDef = Y.merge({ type: type }, config);
                }
            
                if (eventDef) {
                    if (force || !Y.Node.DOM_EVENTS[eventDef.type]) {
                        Impl = function () {
                            SyntheticEvent.apply(this, arguments);
                        };
                        Y.extend(Impl, SyntheticEvent, eventDef);
                        synth = new Impl();
            
                        type = synth.type;
            
                        Y.Node.DOM_EVENTS[type] = Y.Env.evt.plugins[type] = {
                            eventDef: synth,
            
                            on: function () {
                                return synth._on(toArray(arguments));
                            },
            
                            delegate: function () {
                                return synth._on(toArray(arguments), true);
                            },
            
                            detach: function () {
                                return synth._detach(toArray(arguments));
                            }
                        };
            
                    }
                } else if (isString(type) || isArray(type)) {
                    Y.Array.each(toArray(type), function (t) {
                        Y.Node.DOM_EVENTS[t] = 1;
                    });
                }
            
                return synth;
            };