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/**
 * The YUI module contains the components required for building the YUI seed
 * file.  This includes the script loading mechanism, a simple queue, and
 * the core utilities for the library.
 * @module yui
 * @submodule yui-base
 */

if (typeof YUI != 'undefined') {
    YUI._YUI = YUI;
}

/**
 * The YUI global namespace object.  If YUI is already defined, the
 * existing YUI object will not be overwritten so that defined
 * namespaces are preserved.  It is the constructor for the object
 * the end user interacts with.  As indicated below, each instance
 * has full custom event support, but only if the event system
 * is available.  This is a self-instantiable factory function.  You
 * can invoke it directly like this:
 *
 * YUI().use('*', function(Y) {
 *   // ready
 * });
 *
 * But it also works like this:
 *
 * var Y = YUI();
 *
 * @class YUI
 * @constructor
 * @global
 * @uses EventTarget
 * @param o* {object} 0..n optional configuration objects.  these values
 * are store in Y.config.  See config for the list of supported
 * properties.
 */
    /*global YUI*/
    /*global YUI_config*/
    var YUI = function() {
        var i = 0,
            Y = this,
            args = arguments,
            l = args.length,
            instanceOf = function(o, type) {
                return (o && o.hasOwnProperty && (o instanceof type));
            },
            gconf = (typeof YUI_config !== 'undefined') && YUI_config;

        if (!(instanceOf(Y, YUI))) {
            Y = new YUI();
        } else {
            // set up the core environment
            Y._init();

            // YUI.GlobalConfig is a master configuration that might span
            // multiple contexts in a non-browser environment.  It is applied
            // first to all instances in all contexts.
            if (YUI.GlobalConfig) {
                Y.applyConfig(YUI.GlobalConfig);
            }

            // YUI_Config is a page-level config.  It is applied to all
            // instances created on the page.  This is applied after
            // YUI.GlobalConfig, and before the instance level configuration
            // objects.
            if (gconf) {
                Y.applyConfig(gconf);
            }

            // bind the specified additional modules for this instance
            if (!l) {
                Y._setup();
            }
        }

        if (l) {
            // Each instance can accept one or more configuration objects.
            // These are applied after YUI.GlobalConfig and YUI_Config,
            // overriding values set in those config files if there is a '
            // matching property.
            for (; i < l; i++) {
                Y.applyConfig(args[i]);
            }

            Y._setup();
        }

        Y.instanceOf = instanceOf;

        return Y;
    };

(function() {

    var proto, prop,
        VERSION = '@VERSION@',
        PERIOD = '.',
        BASE = 'http://yui.yahooapis.com/',
        DOC_LABEL = 'yui3-js-enabled',
        NOOP = function() {},
        SLICE = Array.prototype.slice,
        APPLY_TO_AUTH = { 'io.xdrReady': 1,   // the functions applyTo
                          'io.xdrResponse': 1,   // can call. this should
                          'SWF.eventHandler': 1 }, // be done at build time
        hasWin = (typeof window != 'undefined'),
        win = (hasWin) ? window : null,
        doc = (hasWin) ? win.document : null,
        docEl = doc && doc.documentElement,
        docClass = docEl && docEl.className,
        instances = {},
        time = new Date().getTime(),
        add = function(el, type, fn, capture) {
            if (el && el.addEventListener) {
                el.addEventListener(type, fn, capture);
            } else if (el && el.attachEvent) {
                el.attachEvent('on' + type, fn);
            }
        },
        remove = function(el, type, fn, capture) {
            if (el && el.removeEventListener) {
                // this can throw an uncaught exception in FF
                try {
                    el.removeEventListener(type, fn, capture);
                } catch (ex) {}
            } else if (el && el.detachEvent) {
                el.detachEvent('on' + type, fn);
            }
        },
        handleLoad = function() {
            YUI.Env.windowLoaded = true;
            YUI.Env.DOMReady = true;
            if (hasWin) {
                remove(window, 'load', handleLoad);
            }
        },
        getLoader = function(Y, o) {
            var loader = Y.Env._loader;
            if (loader) {
                loader.ignoreRegistered = false;
                loader.onEnd = null;
                loader.data = null;
                loader.required = [];
                loader.loadType = null;
            } else {
                loader = new Y.Loader(Y.config);
                Y.Env._loader = loader;
            }

            return loader;
        },

        clobber = function(r, s) {
            for (var i in s) {
                if (s.hasOwnProperty(i)) {
                    r[i] = s[i];
                }
            }
        },

        ALREADY_DONE = { success: true };

//  Stamp the documentElement (HTML) with a class of "yui-loaded" to
//  enable styles that need to key off of JS being enabled.
if (docEl && docClass.indexOf(DOC_LABEL) == -1) {
    if (docClass) {
        docClass += ' ';
    }
    docClass += DOC_LABEL;
    docEl.className = docClass;
}

if (VERSION.indexOf('@') > -1) {
    VERSION = '3.2.0'; // dev time hack for cdn test
}

proto = {
    /**
     * Applies a new configuration object to the YUI instance config.
     * This will merge new group/module definitions, and will also
     * update the loader cache if necessary.  Updating Y.config directly
     * will not update the cache.
     * @method applyConfig
     * @param {object} the configuration object.
     * @since 3.2.0
     */
    applyConfig: function(o) {

        o = o || NOOP;

        var attr,
            name,
            // detail,
            config = this.config,
            mods = config.modules,
            groups = config.groups,
            rls = config.rls,
            loader = this.Env._loader;

        for (name in o) {
            if (o.hasOwnProperty(name)) {
                attr = o[name];
                if (mods && name == 'modules') {
                    clobber(mods, attr);
                } else if (groups && name == 'groups') {
                    clobber(groups, attr);
                } else if (rls && name == 'rls') {
                    clobber(rls, attr);
                } else if (name == 'win') {
                    config[name] = attr.contentWindow || attr;
                    config.doc = config[name].document;
                } else if (name == '_yuid') {
                    // preserve the guid
                } else {
                    config[name] = attr;
                }
            }
        }

        if (loader) {
            loader._config(o);
        }
    },

    _config: function(o) {
        this.applyConfig(o);
    },

    /**
     * Initialize this YUI instance
     * @private
     */
    _init: function() {
        var filter,
            Y = this,
            G_ENV = YUI.Env,
            Env = Y.Env,
            prop;

        /**
         * The version number of the YUI instance.
         * @property version
         * @type string
         */
        Y.version = VERSION;

        if (!Env) {
            Y.Env = {
                mods: {}, // flat module map
                versions: {}, // version module map
                base: BASE,
                cdn: BASE + VERSION + '/build/',
                // bootstrapped: false,
                _idx: 0,
                _used: {},
                _attached: {},
                _yidx: 0,
                _uidx: 0,
                _guidp: 'y',
                _loaded: {},
                serviced: {},
                getBase: G_ENV && G_ENV.getBase ||

    function(srcPattern, comboPattern) {
        var b, nodes, i, src, match;
        // get from querystring
        nodes = (doc && doc.getElementsByTagName('script')) || [];
        for (i = 0; i < nodes.length; i = i + 1) {
            src = nodes[i].src;
            if (src) {

                match = src.match(srcPattern);
                b = match && match[1];
                if (b) {
                    // this is to set up the path to the loader.  The file
                    // filter for loader should match the yui include.
                    filter = match[2];

                    if (filter) {
                        match = filter.indexOf('js');

                        if (match > -1) {
                            filter = filter.substr(0, match);
                        }
                    }

                    // extract correct path for mixed combo urls
                    // http://yuilibrary.com/projects/yui3/ticket/2528423
                    match = src.match(comboPattern);
                    if (match && match[3]) {
                        b = match[1] + match[3];
                    }

                    break;
                }
            }
        }

        // use CDN default
        return b || Env.cdn;
    }
            };

            Env = Y.Env;

            Env._loaded[VERSION] = {};

            if (G_ENV && Y !== YUI) {
                Env._yidx = ++G_ENV._yidx;
                Env._guidp = ('yui_' + VERSION + '_' +
                             Env._yidx + '_' + time).replace(/\./g, '_');
            } else if (YUI._YUI) {

                G_ENV = YUI._YUI.Env;
                Env._yidx += G_ENV._yidx;
                Env._uidx += G_ENV._uidx;

                for (prop in G_ENV) {
                    if (!(prop in Env)) {
                        Env[prop] = G_ENV[prop];
                    }
                }

                delete YUI._YUI;
            }

            Y.id = Y.stamp(Y);
            instances[Y.id] = Y;

        }

        Y.constructor = YUI;

        // configuration defaults
        Y.config = Y.config || {
            win: win,
            doc: doc,
            debug: true,
            useBrowserConsole: true,
            throwFail: true,
            bootstrap: true,
            fetchCSS: true
        };

        Y.config.base = YUI.config.base ||
            Y.Env.getBase(/^(.*)yui\/yui([\.\-].*)js(\?.*)?$/,
                          /^(.*\?)(.*\&)(.*)yui\/yui[\.\-].*js(\?.*)?$/);

        if (!filter || (!('-min.-debug.').indexOf(filter))) {
            filter = '-min.';
        }

        Y.config.loaderPath = YUI.config.loaderPath ||
            'loader/loader' + (filter || '-min.') + 'js';

    },

    /**
     * Finishes the instance setup. Attaches whatever modules were defined
     * when the yui modules was registered.
     * @method _setup
     * @private
     */
    _setup: function(o) {
        var i, Y = this,
            core = [],
            mods = YUI.Env.mods,
            extras = Y.config.core || ['get',
                                        'rls',
                                        'intl-base',
                                        'loader',
                                        'yui-log',
                                        'yui-later',
                                        'yui-throttle'];

        for (i = 0; i < extras.length; i++) {
            if (mods[extras[i]]) {
                core.push(extras[i]);
            }
        }

        Y._attach(['yui-base']);
        Y._attach(core);

        // Y.log(Y.id + ' initialized', 'info', 'yui');
    },

    /**
     * Executes a method on a YUI instance with
     * the specified id if the specified method is whitelisted.
     * @method applyTo
     * @param id {string} the YUI instance id.
     * @param method {string} the name of the method to exectute.
     * Ex: 'Object.keys'.
     * @param args {Array} the arguments to apply to the method.
     * @return {object} the return value from the applied method or null.
     */
    applyTo: function(id, method, args) {
        if (!(method in APPLY_TO_AUTH)) {
            this.log(method + ': applyTo not allowed', 'warn', 'yui');
            return null;
        }

        var instance = instances[id], nest, m, i;
        if (instance) {
            nest = method.split('.');
            m = instance;
            for (i = 0; i < nest.length; i = i + 1) {
                m = m[nest[i]];
                if (!m) {
                    this.log('applyTo not found: ' + method, 'warn', 'yui');
                }
            }
            return m.apply(instance, args);
        }

        return null;
    },

    /**
     * Registers a module with the YUI global.  The easiest way to create a
     * first-class YUI module is to use the YUI component build tool.
     *
     * http://yuilibrary.com/projects/builder
     *
     * The build system will produce the YUI.add wrapper for you module, along
     * with any configuration info required for the module.
     * @method add
     * @param name {string} module name.
     * @param fn {Function} entry point into the module that
     * is used to bind module to the YUI instance.
     * @param version {string} version string.
     * @param details {object} optional config data:
     * requires: features that must be present before this module can be
     * attached.
     * optional: optional features that should be present if loadOptional
     * is defined.  Note: modules are not often loaded this way in YUI 3,
     * but this field is still useful to inform the user that certain
     * features in the component will require additional dependencies.
     * use: features that are included within this module which need to
     * be attached automatically when this module is attached.  This
     * supports the YUI 3 rollup system -- a module with submodules
     * defined will need to have the submodules listed in the 'use'
     * config.  The YUI component build tool does this for you.
     * @return {YUI} the YUI instance.
     *
     */
    add: function(name, fn, version, details) {
        details = details || {};
        var env = YUI.Env,
            mod = {
                name: name,
                fn: fn,
                version: version,
                details: details
            },
            loader,
            i, versions = env.versions;

        env.mods[name] = mod;
        versions[version] = versions[version] || {};
        versions[version][name] = mod;

        for (i in instances) {
            if (instances.hasOwnProperty(i)) {
                loader = instances[i].Env._loader;
                if (loader) {
                    if (!loader.moduleInfo[name]) {
                        loader.addModule(details, name);
                    }
                }
            }
        }

        return this;
    },

    /**
     * Executes the function associated with each required
     * module, binding the module to the YUI instance.
     * @method _attach
     * @private
     */
    _attach: function(r, fromLoader) {
        var i, name, mod, details, req, use, after,
            mods = YUI.Env.mods,
            Y = this, j,
            done = Y.Env._attached,
            len = r.length, loader;

        // Y.log('attaching: ' + r, 'info', 'yui');

        for (i = 0; i < len; i++) {
            if (!done[r[i]]) {
                name = r[i];
                mod = mods[name];
                if (!mod) {
                    loader = Y.Env._loader;

                    // Y.log('no js def for: ' + name, 'info', 'yui');

                    if (!loader || !loader.moduleInfo[name]) {
                        Y.message('NOT loaded: ' + name, 'warn', 'yui');
                    }
                } else {
                    done[name] = true;
                    details = mod.details;
                    req = details.requires;
                    use = details.use;
                    after = details.after;

                    if (req) {
                        for (j = 0; j < req.length; j++) {
                            if (!done[req[j]]) {
                                if (!Y._attach(req)) {
                                    return false;
                                }
                                break;
                            }
                        }
                    }

                    if (after) {
                        for (j = 0; j < after.length; j++) {
                            if (!done[after[j]]) {
                                if (!Y._attach(after)) {
                                    return false;
                                }
                                break;
                            }
                        }
                    }


                    if (use) {
                        for (j = 0; j < use.length; j++) {
                            if (!done[use[j]]) {
                                if (!Y._attach(use)) {
                                    return false;
                                }
                                break;
                            }
                        }
                    }

                    if (mod.fn) {
                        try {
                            mod.fn(Y, name);
                        } catch (e) {
                            Y.error('Attach error: ' + name, e, name);
                            return false;
                        }
                    }

                }
            }
        }

        return true;
    },

    /**
     * Attaches one or more modules to the YUI instance.  When this
     * is executed, the requirements are analyzed, and one of
     * several things can happen:
     *
     * - All requirements are available on the page --  The modules
     *   are attached to the instance.  If supplied, the use callback
     *   is executed synchronously.
     *
     * - Modules are missing, the Get utility is not available OR
     *   the 'bootstrap' config is false -- A warning is issued about
     *   the missing modules and all available modules are attached.
     *
     * - Modules are missing, the Loader is not available but the Get
     *   utility is and boostrap is not false -- The loader is bootstrapped
     *   before doing the following....
     *
     * - Modules are missing and the Loader is available -- The loader
     *   expands the dependency tree and fetches missing modules.  When
     *   the loader is finshed the callback supplied to use is executed
     *   asynchronously.
     *
     * @param modules* {string} 1-n modules to bind (uses arguments array).
     * @param *callback {function} callback function executed when
     * the instance has the required functionality.  If included, it
     * must be the last parameter.
     * <code>
     * // loads and attaches drag and drop and its dependencies
     * YUI().use('dd', function(Y) &#123;&#125);
     * // attaches all modules that are available on the page
     * YUI().use('*', function(Y) &#123;&#125);
     * // intrinsic YUI gallery support (since 3.1.0)
     * YUI().use('gallery-yql', function(Y) &#123;&#125);
     * // intrinsic YUI 2in3 support (since 3.1.0)
     * YUI().use('yui2-datatable', function(Y) &#123;&#125);.
     * </code>
     *
     * @return {YUI} the YUI instance.
     */
    use: function() {
        var args = SLICE.call(arguments, 0),
            callback = args[args.length - 1],
            Y = this,
            key;

        // The last argument supplied to use can be a load complete callback
        if (Y.Lang.isFunction(callback)) {
            args.pop();
        } else {
            callback = null;
        }

        if (Y._loading) {
            Y._useQueue = Y._useQueue || new Y.Queue();
            Y._useQueue.add([args, callback]);
        } else {
            key = args.join();

            if (Y.Env.serviced[key]) {
                Y.log('already provisioned: ' + key, 'info', 'yui');
                Y._notify(callback, ALREADY_DONE, args);
            } else {
                Y._use(args, function(Y, response) {
                    Y.log('caching request: ' + key, 'info', 'yui');
                    Y.Env.serviced[key] = true;
                    Y._notify(callback, response, args);
                });
            }
        }

        return Y;
    },

    _notify: function(callback, response, args) {
        if (callback) {
            try {
                callback(this, response);
            } catch (e) {
                this.error('use callback error', e, args);
            }
        }
    },

    _use: function(args, callback) {

        if (!this.Array) {
            this._attach(['yui-base']);
        }

        var len, loader, handleBoot,
            Y = this,
            G_ENV = YUI.Env,
            mods = G_ENV.mods,
            Env = Y.Env,
            used = Env._used,
            queue = G_ENV._loaderQueue,
            firstArg = args[0],
            YArray = Y.Array,
            config = Y.config,
            boot = config.bootstrap,
            missing = [],
            r = [],
            ret = true,
            fetchCSS = config.fetchCSS,
            process = function(names, skip) {

                if (!names.length) {
                    return;
                }

                YArray.each(names, function(name) {

                    // add this module to full list of things to attach
                    if (!skip) {
                        r.push(name);
                    }

                    // only attach a module once
                    if (used[name]) {
                        return;
                    }

                    var m = mods[name], req, use;

                    if (m) {
                        used[name] = true;
                        req = m.details.requires;
                        use = m.details.use;
                    } else {
                        // CSS files don't register themselves, see if it has
                        // been loaded
                        if (!G_ENV._loaded[VERSION][name]) {
                            missing.push(name);
                        } else {
                            used[name] = true; // probably css
                        }
                    }

                    // make sure requirements are attached
                    if (req && req.length) {
                        process(req);
                    }

                    // make sure we grab the submodule dependencies too
                    if (use && use.length) {
                        process(use, 1);
                    }
                });
            },

            handleLoader = function(fromLoader) {
                var response = fromLoader || {
                        success: true,
                        msg: 'not dynamic'
                    },
                    redo, origMissing,
                    ret = true,
                    data = response.data;


                Y._loading = false;

                if (data) {
                    origMissing = missing;
                    missing = [];
                    r = [];
                    process(data);
                    redo = missing.length;
                    if (redo) {
                        if (missing.sort().join() ==
                                origMissing.sort().join()) {
                            redo = false;
                        }
                    }
                }

                if (redo && data) {
                    Y._loading = false;
                    Y._use(args, function() {
                        Y.log('Nested use callback: ' + data, 'info', 'yui');
                        if (Y._attach(data)) {
                            Y._notify(callback, response, data);
                        }
                    });
                } else {
                    if (data) {
                        // Y.log('attaching from loader: ' + data, 'info', 'yui');
                        ret = Y._attach(data);
                    }
                    if (ret) {
                        Y._notify(callback, response, args);
                    }
                }

                if (Y._useQueue && Y._useQueue.size() && !Y._loading) {
                    Y._use.apply(Y, Y._useQueue.next());
                }

            };

// Y.log(Y.id + ': use called: ' + a + ' :: ' + callback, 'info', 'yui');

        // YUI().use('*'); // bind everything available
        if (firstArg === '*') {
            ret = Y._attach(Y.Object.keys(mods));
            if (ret) {
                handleLoader();
            }
            return Y;
        }

        // Y.log('before loader requirements: ' + args, 'info', 'yui');

        // use loader to expand dependencies and sort the
        // requirements if it is available.
        if (boot && Y.Loader && args.length) {
            loader = getLoader(Y);
            loader.require(args);
            loader.ignoreRegistered = true;
            loader.calculate(null, (fetchCSS) ? null : 'js');
            args = loader.sorted;
        }

        // process each requirement and any additional requirements
        // the module metadata specifies
        process(args);

        len = missing.length;

        if (len) {
            missing = Y.Object.keys(YArray.hash(missing));
            len = missing.length;
Y.log('Modules missing: ' + missing + ', ' + missing.length, 'info', 'yui');
        }

        // dynamic load
        if (boot && len && Y.Loader) {
// Y.log('Using loader to fetch missing deps: ' + missing, 'info', 'yui');
            Y.log('Using Loader', 'info', 'yui');
            Y._loading = true;
            loader = getLoader(Y);
            loader.onEnd = handleLoader;
            loader.context = Y;
            loader.data = args;
            loader.ignoreRegistered = false;
            loader.require(args);
            loader.insert(null, (fetchCSS) ? null : 'js');
            // loader.partial(missing, (fetchCSS) ? null : 'js');

        } else if (len && Y.config.use_rls) {

            // server side loader service
            Y.Get.script(Y._rls(args), {
                onEnd: function(o) {
                    handleLoader(o);
                },
                data: args
            });

        } else if (boot && len && Y.Get && !Env.bootstrapped) {

            Y._loading = true;

            handleBoot = function() {
                Y._loading = false;
                queue.running = false;
                Env.bootstrapped = true;
                if (Y._attach(['loader'])) {
                    Y._use(args, callback);
                }
            };

            if (G_ENV._bootstrapping) {
Y.log('Waiting for loader', 'info', 'yui');
                queue.add(handleBoot);
            } else {
                G_ENV._bootstrapping = true;
Y.log('Fetching loader: ' + config.base + config.loaderPath, 'info', 'yui');
                Y.Get.script(config.base + config.loaderPath, {
                    onEnd: handleBoot
                });
            }

        } else {
            Y.log('Attaching available dependencies: ' + args, 'info', 'yui');
            ret = Y._attach(args);
            if (ret) {
                handleLoader();
            }
        }

        return Y;
    },


    /**
     * Returns the namespace specified and creates it if it doesn't exist
     * <pre>
     * YUI.namespace("property.package");
     * YUI.namespace("YAHOO.property.package");
     * </pre>
     * Either of the above would create YUI.property, then
     * YUI.property.package (YAHOO is scrubbed out, this is
     * to remain compatible with YUI2)
     *
     * Be careful when naming packages. Reserved words may work in some browsers
     * and not others. For instance, the following will fail in Safari:
     * <pre>
     * YUI.namespace("really.long.nested.namespace");
     * </pre>
     * This fails because "long" is a future reserved word in ECMAScript
     *
     * @method namespace
     * @param  {string*} arguments 1-n namespaces to create.
     * @return {object}  A reference to the last namespace object created.
     */
    namespace: function() {
        var a = arguments, o = this, i = 0, j, d, arg;
        for (; i < a.length; i++) {
            // d = ('' + a[i]).split('.');
            arg = a[i];
            if (arg.indexOf(PERIOD)) {
                d = arg.split(PERIOD);
                for (j = (d[0] == 'YAHOO') ? 1 : 0; j < d.length; j++) {
                    o[d[j]] = o[d[j]] || {};
                    o = o[d[j]];
                }
            } else {
                o[arg] = o[arg] || {};
            }
        }
        return o;
    },

    // this is replaced if the log module is included
    log: NOOP,
    message: NOOP,

    /**
     * Report an error.  The reporting mechanism is controled by
     * the 'throwFail' configuration attribute.  If throwFail is
     * not specified, the message is written to the Logger, otherwise
     * a JS error is thrown
     * @method error
     * @param msg {string} the error message.
     * @param e {Error} Optional JS error that was caught.  If supplied
     * and throwFail is specified, this error will be re-thrown.
     * @return {YUI} this YUI instance.
     */
    error: function(msg, e) {

        var Y = this, ret;

        if (Y.config.errorFn) {
            ret = Y.config.errorFn.apply(Y, arguments);
        }

        if (Y.config.throwFail && !ret) {
            throw (e || new Error(msg));
        } else {
            Y.message(msg, 'error'); // don't scrub this one
        }

        return Y;
    },

    /**
     * Generate an id that is unique among all YUI instances
     * @method guid
     * @param pre {string} optional guid prefix.
     * @return {string} the guid.
     */
    guid: function(pre) {
        var id = this.Env._guidp + (++this.Env._uidx);
        return (pre) ? (pre + id) : id;
    },

    /**
     * Returns a guid associated with an object.  If the object
     * does not have one, a new one is created unless readOnly
     * is specified.
     * @method stamp
     * @param o The object to stamp.
     * @param readOnly {boolean} if true, a valid guid will only
     * be returned if the object has one assigned to it.
     * @return {string} The object's guid or null.
     */
    stamp: function(o, readOnly) {
        var uid;
        if (!o) {
            return o;
        }

        // IE generates its own unique ID for dom nodes
        // The uniqueID property of a document node returns a new ID
        if (o.uniqueID && o.nodeType && o.nodeType !== 9) {
            uid = o.uniqueID;
        } else {
            uid = (typeof o === 'string') ? o : o._yuid;
        }

        if (!uid) {
            uid = this.guid();
            if (!readOnly) {
                try {
                    o._yuid = uid;
                } catch (e) {
                    uid = null;
                }
            }
        }
        return uid;
    },

    /**
     * Destroys the YUI instance
     * @method destroy
     * @since 3.3.0
     */
    destroy: function() {
        var Y = this;
        if (Y.Event) {
            Y.Event._unload();
        }
        delete instances[Y.id];
        delete Y.Env;
        delete Y.config;
    }

    /**
     * instanceof check for objects that works around
     * memory leak in IE when the item tested is
     * window/document
     * @method instanceOf
     * @since 3.3.0
     */
};



    YUI.prototype = proto;

    // inheritance utilities are not available yet
    for (prop in proto) {
        if (proto.hasOwnProperty(prop)) {
            YUI[prop] = proto[prop];
        }
    }

    // set up the environment
    YUI._init();

    if (hasWin) {
        // add a window load event at load time so we can capture
        // the case where it fires before dynamic loading is
        // complete.
        add(window, 'load', handleLoad);
    } else {
        handleLoad();
    }

    YUI.Env.add = add;
    YUI.Env.remove = remove;

    /*global exports*/
    // Support the CommonJS method for exporting our single global
    if (typeof exports == 'object') {
        exports.YUI = YUI;
    }

}());


/**
 * The config object contains all of the configuration options for
 * the YUI instance.  This object is supplied by the implementer
 * when instantiating a YUI instance.  Some properties have default
 * values if they are not supplied by the implementer.  This should
 * not be updated directly because some values are cached.  Use
 * applyConfig() to update the config object on a YUI instance that
 * has already been configured.
 *
 * @class config
 * @static
 */

/**
 * Allows the YUI seed file to fetch the loader component and library
 * metadata to dynamically load additional dependencies.
 *
 * @property bootstrap
 * @type boolean
 * @default true
 */

/**
 * Log to the browser console if debug is on and the browser has a
 * supported console.
 *
 * @property useBrowserConsole
 * @type boolean
 * @default true
 */

/**
 * A hash of log sources that should be logged.  If specified, only
 * log messages from these sources will be logged.
 *
 * @property logInclude
 * @type object
 */

/**
 * A hash of log sources that should be not be logged.  If specified,
 * all sources are logged if not on this list.
 *
 * @property logExclude
 * @type object
 */

/**
 * Set to true if the yui seed file was dynamically loaded in
 * order to bootstrap components relying on the window load event
 * and the 'domready' custom event.
 *
 * @property injected
 * @type boolean
 * @default false
 */

/**
 * If throwFail is set, Y.error will generate or re-throw a JS Error.
 * Otherwise the failure is logged.
 *
 * @property throwFail
 * @type boolean
 * @default true
 */

/**
 * The window/frame that this instance should operate in.
 *
 * @property win
 * @type Window
 * @default the window hosting YUI
 */

/**
 * The document associated with the 'win' configuration.
 *
 * @property doc
 * @type Document
 * @default the document hosting YUI
 */

/**
 * A list of modules that defines the YUI core (overrides the default).
 *
 * @property core
 * @type string[]
 */

/**
 * A list of languages in order of preference. This list is matched against
 * the list of available languages in modules that the YUI instance uses to
 * determine the best possible localization of language sensitive modules.
 * Languages are represented using BCP 47 language tags, such as "en-GB" for
 * English as used in the United Kingdom, or "zh-Hans-CN" for simplified
 * Chinese as used in China. The list can be provided as a comma-separated
 * list or as an array.
 *
 * @property lang
 * @type string|string[]
 */

/**
 * The default date format
 * @property dateFormat
 * @type string
 * @deprecated use configuration in DataType.Date.format() instead.
 */

/**
 * The default locale
 * @property locale
 * @type string
 * @deprecated use config.lang instead.
 */

/**
 * The default interval when polling in milliseconds.
 * @property pollInterval
 * @type int
 * @default 20
 */

/**
 * The number of dynamic nodes to insert by default before
 * automatically removing them.  This applies to script nodes
 * because remove the node will not make the evaluated script
 * unavailable.  Dynamic CSS is not auto purged, because removing
 * a linked style sheet will also remove the style definitions.
 * @property purgethreshold
 * @type int
 * @default 20
 */

/**
 * The default interval when polling in milliseconds.
 * @property windowResizeDelay
 * @type int
 * @default 40
 */

/**
 * Base directory for dynamic loading
 * @property base
 * @type string
 */

/*
 * The secure base dir (not implemented)
 * For dynamic loading.
 * @property secureBase
 * @type string
 */

/**
 * The YUI combo service base dir. Ex: http://yui.yahooapis.com/combo?
 * For dynamic loading.
 * @property comboBase
 * @type string
 */

/**
 * The root path to prepend to module path for the combo service.
 * Ex: 3.0.0b1/build/
 * For dynamic loading.
 * @property root
 * @type string
 */

/**
 * A filter to apply to result urls.  This filter will modify the default
 * path for all modules.  The default path for the YUI library is the
 * minified version of the files (e.g., event-min.js).  The filter property
 * can be a predefined filter or a custom filter.  The valid predefined
 * filters are:
 * <dl>
 *  <dt>DEBUG</dt>
 *  <dd>Selects the debug versions of the library (e.g., event-debug.js).
 *      This option will automatically include the Logger widget</dd>
 *  <dt>RAW</dt>
 *  <dd>Selects the non-minified version of the library (e.g., event.js).</dd>
 * </dl>
 * You can also define a custom filter, which must be an object literal
 * containing a search expression and a replace string:
 * <pre>
 *  myFilter: &#123;
 *      'searchExp': "-min\\.js",
 *      'replaceStr': "-debug.js"
 *  &#125;
 * </pre>
 *
 * For dynamic loading.
 *
 * @property filter
 * @type string|object
 */

/**
 * The 'skin' config let's you configure application level skin
 * customizations.  It contains the following attributes which
 * can be specified to override the defaults:
 *
 *      // The default skin, which is automatically applied if not
 *      // overriden by a component-specific skin definition.
 *      // Change this in to apply a different skin globally
 *      defaultSkin: 'sam',
 *
 *      // This is combined with the loader base property to get
 *      // the default root directory for a skin.
 *      base: 'assets/skins/',
 *
 *      // Any component-specific overrides can be specified here,
 *      // making it possible to load different skins for different
 *      // components.  It is possible to load more than one skin
 *      // for a given component as well.
 *      overrides: {
 *          slider: ['capsule', 'round']
 *      }
 *
 * For dynamic loading.
 *
 *  @property skin
 */

/**
 * Hash of per-component filter specification.  If specified for a given
 * component, this overrides the filter config.
 *
 * For dynamic loading.
 *
 * @property filters
 */

/**
 * Use the YUI combo service to reduce the number of http connections
 * required to load your dependencies.  Turning this off will
 * disable combo handling for YUI and all module groups configured
 * with a combo service.
 *
 * For dynamic loading.
 *
 * @property combine
 * @type boolean
 * @default true if 'base' is not supplied, false if it is.
 */

/**
 * A list of modules that should never be dynamically loaded
 *
 * @property ignore
 * @type string[]
 */

/**
 * A list of modules that should always be loaded when required, even if already
 * present on the page.
 *
 * @property force
 * @type string[]
 */

/**
 * Node or id for a node that should be used as the insertion point for new
 * nodes.  For dynamic loading.
 *
 * @property insertBefore
 * @type string
 */

/**
 * Object literal containing attributes to add to dynamically loaded script
 * nodes.
 * @property jsAttributes
 * @type string
 */

/**
 * Object literal containing attributes to add to dynamically loaded link
 * nodes.
 * @property cssAttributes
 * @type string
 */

/**
 * Number of milliseconds before a timeout occurs when dynamically
 * loading nodes. If not set, there is no timeout.
 * @property timeout
 * @type int
 */

/**
 * Callback for the 'CSSComplete' event.  When dynamically loading YUI
 * components with CSS, this property fires when the CSS is finished
 * loading but script loading is still ongoing.  This provides an
 * opportunity to enhance the presentation of a loading page a little
 * bit before the entire loading process is done.
 *
 * @property onCSS
 * @type function
 */

/**
 * A hash of module definitions to add to the list of YUI components.
 * These components can then be dynamically loaded side by side with
 * YUI via the use() method. This is a hash, the key is the module
 * name, and the value is an object literal specifying the metdata
 * for the module.  * See Loader.addModule for the supported module
 * metadata fields.  Also @see groups, which provides a way to
 * configure the base and combo spec for a set of modules.
 * <code>
 * modules: {
 * &nbsp; mymod1: {
 * &nbsp;   requires: ['node'],
 * &nbsp;   fullpath: 'http://myserver.mydomain.com/mymod1/mymod1.js'
 * &nbsp; },
 * &nbsp; mymod2: {
 * &nbsp;   requires: ['mymod1'],
 * &nbsp;   fullpath: 'http://myserver.mydomain.com/mymod2/mymod2.js'
 * &nbsp; }
 * }
 * </code>
 *
 * @property modules
 * @type object
 */

/**
 * A hash of module group definitions.  It for each group you
 * can specify a list of modules and the base path and
 * combo spec to use when dynamically loading the modules.  @see
 * @see modules for the details about the modules part of the
 * group definition.
 * <code>
 * &nbsp; groups: {
 * &nbsp;     yui2: {
 * &nbsp;         // specify whether or not this group has a combo service
 * &nbsp;         combine: true,
 * &nbsp;
 * &nbsp;         // the base path for non-combo paths
 * &nbsp;         base: 'http://yui.yahooapis.com/2.8.0r4/build/',
 * &nbsp;
 * &nbsp;         // the path to the combo service
 * &nbsp;         comboBase: 'http://yui.yahooapis.com/combo?',
 * &nbsp;
 * &nbsp;         // a fragment to prepend to the path attribute when
 * &nbsp;         // when building combo urls
 * &nbsp;         root: '2.8.0r4/build/',
 * &nbsp;
 * &nbsp;         // the module definitions
 * &nbsp;         modules:  {
 * &nbsp;             yui2_yde: {
 * &nbsp;                 path: "yahoo-dom-event/yahoo-dom-event.js"
 * &nbsp;             },
 * &nbsp;             yui2_anim: {
 * &nbsp;                 path: "animation/animation.js",
 * &nbsp;                 requires: ['yui2_yde']
 * &nbsp;             }
 * &nbsp;         }
 * &nbsp;     }
 * &nbsp; }
 * </code>
 * @property modules
 * @type object
 */

/**
 * The loader 'path' attribute to the loader itself.  This is combined
 * with the 'base' attribute to dynamically load the loader component
 * when boostrapping with the get utility alone.
 *
 * @property loaderPath
 * @type string
 * @default loader/loader-min.js
 */

/**
 * Specifies whether or not YUI().use(...) will attempt to load CSS
 * resources at all.  Any truthy value will cause CSS dependencies
 * to load when fetching script.  The special value 'force' will
 * cause CSS dependencies to be loaded even if no script is needed.
 *
 * @property fetchCSS
 * @type boolean|string
 * @default true
 */

/**
 * The default gallery version to build gallery module urls
 * @property gallery
 * @type string
 * @since 3.1.0
 */

/**
 * The default YUI 2 version to build yui2 module urls.  This is for
 * intrinsic YUI 2 support via the 2in3 project.  Also @see the '2in3'
 * config for pulling different revisions of the wrapped YUI 2
 * modules.
 * @since 3.1.0
 * @property yui2
 * @type string
 * @default 2.8.1
 */

/**
 * The 2in3 project is a deployment of the various versions of YUI 2
 * deployed as first-class YUI 3 modules.  Eventually, the wrapper
 * for the modules will change (but the underlying YUI 2 code will
 * be the same), and you can select a particular version of
 * the wrapper modules via this config.
 * @since 3.1.0
 * @property 2in3
 * @type string
 * @default 1
 */

/**
 * Alternative console log function for use in environments without
 * a supported native console.  The function is executed in the
 * YUI instance context.
 * @since 3.1.0
 * @property logFn
 * @type Function
 */

/**
 * A callback to execute when Y.error is called.  It receives the
 * error message and an javascript error object if Y.error was
 * executed because a javascript error was caught.  The function
 * is executed in the YUI instance context.
 *
 * @since 3.2.0
 * @property errorFn
 * @type Function
 */

/**
 * The parameter defaults for the remote loader service.
 * Requires the rls submodule.  The properties that are
 * supported:
 * <pre>
 * m: comma separated list of module requirements.  This
 *    must be the param name even for custom implemetations.
 * v: the version of YUI to load.  Defaults to the version
 *    of YUI that is being used.
 * gv: the version of the gallery to load (@see the gallery config)
 * env: comma separated list of modules already on the page.
 *      this must be the param name even for custom implemetations.
 * lang: the languages supported on the page (@see the lang config)
 * '2in3v':  the version of the 2in3 wrapper to use (@see the 2in3 config).
 * '2v': the version of yui2 to use in the yui 2in3 wrappers
 *       (@see the yui2 config)
 * filt: a filter def to apply to the urls (@see the filter config).
 * filts: a list of custom filters to apply per module
 *        (@see the filters config).
 * tests: this is a map of conditional module test function id keys
 * with the values of 1 if the test passes, 0 if not.  This must be
 * the name of the querystring param in custom templates.
 *</pre>
 *
 * @since 3.2.0
 * @property rls
 */

/**
 * The base path to the remote loader service
 *
 * @since 3.2.0
 * @property rls_base
 */

/**
 * The template to use for building the querystring portion
 * of the remote loader service url.  The default is determined
 * by the rls config -- each property that has a value will be
 * represented.
 *
 * ex: m={m}&v={v}&env={env}&lang={lang}&filt={filt}&tests={tests}
 *
 *
 * @since 3.2.0
 * @property rls_tmpl
 */

/**
 * Configure the instance to use a remote loader service instead of
 * the client loader.
 *
 * @since 3.2.0
 * @property use_rls
 */

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