    /**
     * A template class that supports advanced functionality like:
     *
     * - Autofilling arrays using templates and sub-templates
     * - Conditional processing with basic comparison operators
     * - Basic math function support
     * - Execute arbitrary inline code with special built-in template variables
     * - Custom member functions
     * - Many special tags and built-in operators that aren't defined as part of the API, but are supported in the templates that can be created
     *
     * XTemplate provides the templating mechanism built into {@link Ext.view.View}.
     *
     * The {@link Ext.Template} describes the acceptable parameters to pass to the constructor. The following examples
     * demonstrate all of the supported features.
     *
     * # Sample Data
     *
     * This is the data object used for reference in each code example:
     *
     *     var data = {
     *         name: 'Don Griffin',
     *         title: 'Senior Technomage',
     *         company: 'Sencha Inc.',
     *         drinks: ['Coffee', 'Water', 'More Coffee'],
     *         kids: [
     *             { name: 'Aubrey',  age: 17 },
     *             { name: 'Joshua',  age: 13 },
     *             { name: 'Cale',    age: 10 },
     *             { name: 'Nikol',   age: 5 },
     *             { name: 'Solomon', age: 0 }
     *         ]
     *     };
     *
     * # Auto filling of arrays
     *
     * The **tpl** tag and the **for** operator are used to process the provided data object:
     *
     * - If the value specified in for is an array, it will auto-fill, repeating the template block inside the tpl
     *   tag for each item in the array.
     * - If for="." is specified, the data object provided is examined.
     * - While processing an array, the special variable {#} will provide the current array index + 1 (starts at 1, not 0).
     *
     * Examples:
     *
     *     <tpl for=".">...</tpl>       // loop through array at root node
     *     <tpl for="foo">...</tpl>     // loop through array at foo node
     *     <tpl for="foo.bar">...</tpl> // loop through array at foo.bar node
     *
     * Using the sample data above:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Kids: ',
     *         '<tpl for=".">',       // process the data.kids node
     *             '<p>{#}. {name}</p>',  // use current array index to autonumber
     *         '</tpl></p>'
     *     );
     *     tpl.overwrite(panel.body, data.kids); // pass the kids property of the data object
     *
     * An example illustrating how the **for** property can be leveraged to access specified members of the provided data
     * object to populate the template:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Title: {title}</p>',
     *         '<p>Company: {company}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',     // interrogate the kids property within the data
     *             '<p>{name}</p>',
     *         '</tpl></p>'
     *     );
     *     tpl.overwrite(panel.body, data);  // pass the root node of the data object
     *
     * Flat arrays that contain values (and not objects) can be auto-rendered using the special **`{.}`** variable inside a
     * loop. This variable will represent the value of the array at the current index:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>{name}\'s favorite beverages:</p>',
     *         '<tpl for="drinks">',
     *             '<div> - {.}</div>',
     *         '</tpl>'
     *     );
     *     tpl.overwrite(panel.body, data);
     *
     * When processing a sub-template, for example while looping through a child array, you can access the parent object's
     * members via the **parent** object:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '<tpl if="age &gt; 1">',
     *                 '<p>{name}</p>',
     *                 '<p>Dad: {parent.name}</p>',
     *             '</tpl>',
     *         '</tpl></p>'
     *     );
     *     tpl.overwrite(panel.body, data);
     *
     * # Conditional processing with basic comparison operators
     *
     * The **tpl** tag and the **if** operator are used to provide conditional checks for deciding whether or not to render
     * specific parts of the template.
     *
     * Using the sample data above:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '<tpl if="age &gt; 1">',
     *                 '<p>{name}</p>',
     *             '</tpl>',
     *         '</tpl></p>'
     *     );
     *     tpl.overwrite(panel.body, data);
     *
     * More advanced conditionals are also supported:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '<p>{name} is a ',
     *             '<tpl if="age &gt;= 13">',
     *                 '<p>teenager</p>',
     *             '<tpl elseif="age &gt;= 2">',
     *                 '<p>kid</p>',
     *             '<tpl else>',
     *                 '<p>baby</p>',
     *             '</tpl>',
     *         '</tpl></p>'
     *     );
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '<p>{name} is a ',
     *             '<tpl switch="name">',
     *                 '<tpl case="Aubrey" case="Nikol">',
     *                     '<p>girl</p>',
     *                 '<tpl default>',
     *                     '<p>boy</p>',
     *             '</tpl>',
     *         '</tpl></p>'
     *     );
     *
     * A `break` is implied between each case and default, however, multiple cases can be listed
     * in a single &lt;tpl&gt; tag.
     *
     * # Using double quotes
     *
     * Examples:
     *
     *     var tpl = new Ext.XTemplate(
     *         "<tpl if='age &gt; 1 && age &lt; 10'>Child</tpl>",
     *         "<tpl if='age &gt;= 10 && age &lt; 18'>Teenager</tpl>",
     *         "<tpl if='this.isGirl(name)'>...</tpl>",
     *         '<tpl if="id == \'download\'">...</tpl>',
     *         "<tpl if='needsIcon'><img src='{icon}' class='{iconCls}'/></tpl>",
     *         "<tpl if='name == \"Don\"'>Hello</tpl>"
     *     );
     *
     * # Basic math support
     *
     * The following basic math operators may be applied directly on numeric data values:
     *
     *     + - * /
     *
     * For example:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '<tpl if="age &gt; 1">',  // <-- Note that the > is encoded
     *                 '<p>{#}: {name}</p>',  // <-- Auto-number each item
     *                 '<p>In 5 Years: {age+5}</p>',  // <-- Basic math
     *                 '<p>Dad: {parent.name}</p>',
     *             '</tpl>',
     *         '</tpl></p>'
     *     );
     *     tpl.overwrite(panel.body, data);
     *
     * # Execute arbitrary inline code with special built-in template variables
     *
     * Anything between `{[ ... ]}` is considered code to be executed in the scope of the template.
     * The expression is evaluated and the result is included in the generated result. There are
     * some special variables available in that code:
     *
     * - **out**: The output array into which the template is being appended (using `push` to later
     *   `join`).
     * - **values**: The values in the current scope. If you are using scope changing sub-templates,
     *   you can change what values is.
     * - **parent**: The scope (values) of the ancestor template.
     * - **xindex**: If you are in a looping template, the index of the loop you are in (1-based).
     * - **xcount**: If you are in a looping template, the total length of the array you are looping.
     *
     * This example demonstrates basic row striping using an inline code block and the xindex variable:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Company: {[values.company.toUpperCase() + ", " + values.title]}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '<div class="{[xindex % 2 === 0 ? "even" : "odd"]}">',
     *             '{name}',
     *             '</div>',
     *         '</tpl></p>'
     *      );
     *
     * Any code contained in "verbatim" blocks (using "{% ... %}") will be inserted directly in
     * the generated code for the template. These blocks are not included in the output. This
     * can be used for simple things like break/continue in a loop, or control structures or
     * method calls (when they don't produce output). The `this` references the template instance.
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Company: {[values.company.toUpperCase() + ", " + values.title]}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '{% if (xindex % 2 === 0) continue; %}',
     *             '{name}',
     *             '{% if (xindex > 100) break; %}',
     *             '</div>',
     *         '</tpl></p>'
     *      );
     *
     * # Template member functions
     *
     * One or more member functions can be specified in a configuration object passed into the XTemplate constructor for
     * more complex processing:
     *
     *     var tpl = new Ext.XTemplate(
     *         '<p>Name: {name}</p>',
     *         '<p>Kids: ',
     *         '<tpl for="kids">',
     *             '<tpl if="this.isGirl(name)">',
     *                 '<p>Girl: {name} - {age}</p>',
     *             '<tpl else>',
     *                 '<p>Boy: {name} - {age}</p>',
     *             '</tpl>',
     *             '<tpl if="this.isBaby(age)">',
     *                 '<p>{name} is a baby!</p>',
     *             '</tpl>',
     *         '</tpl></p>',
     *         {
     *             // XTemplate configuration:
     *             disableFormats: true,
     *             // member functions:
     *             isGirl: function(name){
     *                return name == 'Aubrey' || name == 'Nikol';
     *             },
     *             isBaby: function(age){
     *                return age < 1;
     *             }
     *         }
     *     );
     *     tpl.overwrite(panel.body, data);
     */
    Ext.define('Ext.XTemplate', {
        extend: 'Ext.Template',

        requires: 'Ext.XTemplateCompiler',

        /**
         * @private
         */
        emptyObj: {},

        /**
         * @cfg {Boolean} compiled
         * Only applies to {@link Ext.Template}, XTemplates are compiled automatically on the
         * first call to {@link #apply} or {@link #applyOut}.
         */

        /**
         * @cfg {String/Array} definitions
         * Optional. A statement, or array of statements which set up `var`s which may then
         * be accessed within the scope of the generated function.
         */

        apply: function(values, parent) {
            return this.applyOut(values, [], parent).join('');
        },

        applyOut: function(values, out, parent) {
            var me = this,
                compiler;

            if (!me.fn) {
                compiler = new Ext.XTemplateCompiler({
                    useFormat: me.disableFormats !== true,
                    definitions: me.definitions
                });

                me.fn = compiler.compile(me.html);
            }

            try {
                me.fn.call(me, out, values, parent || me.emptyObj, 1, 1);
            } catch (e) {
                //<debug>
                Ext.log('Error: ' + e.message);
                //</debug>
            }

            return out;
        },

        /**
         * Does nothing. XTemplates are compiled automatically, so this function simply returns this.
         * @return {Ext.XTemplate} this
         */
        compile: function() {
            return this;
        },

        statics: {
            /**
             * Gets an `XTemplate` from an object (an instance of an {@link Ext#define}'d class).
             * Many times, templates are configured high in the class hierarchy and are to be
             * shared by all classes that derive from that base. To further complicate matters,
             * these templates are seldom actual instances but are rather configurations. For
             * example:
             *
             *      Ext.define('MyApp.Class', {
             *          someTpl: [
             *              'tpl text here'
             *          ]
             *      });
             *
             * The goal being to share that template definition with all instances and even
             * instances of derived classes, until `someTpl` is overridden. This method will
             * "upgrade" these configurations to be real `XTemplate` instances *in place* (to
             * avoid creating one instance per object).
             *
             * @param {Object} instance The object from which to get the `XTemplate` (must be
             * an instance of an {@link Ext#define}'d class).
             * @param {String} name The name of the property by which to get the `XTemplate`.
             * @return {Ext.XTemplate} The `XTemplate` instance or null if not found.
             * @protected
             */
            getTpl: function (instance, name) {
                var tpl = instance[name], // go for it! 99% of the time we will get it!
                    proto;

                if (tpl && !tpl.isTemplate) { // tpl is just a configuration (not an instance)
                    // create the template instance from the configuration:
                    tpl = Ext.ClassManager.dynInstantiate('Ext.XTemplate', tpl);

                    // and replace the reference with the new instance:
                    if (instance.hasOwnProperty(name)) { // the tpl is on the instance
                        instance[name] = tpl;
                    } else { // must be somewhere in the prototype chain
                        for (proto = instance.self.prototype; proto; proto = proto.superclass) {
                            if (proto.hasOwnProperty(name)) {
                                proto[name] = tpl;
                                break;
                            }
                        }
                    }
                }
                // else !tpl (no such tpl) or the tpl is an instance already... either way, tpl
                // is ready to return

                return tpl || null;
            }
        }
    });