    /**
     * @author Jacky Nguyen <jacky@sencha.com>
     * @docauthor Jacky Nguyen <jacky@sencha.com>
     * @class Ext.Array
     *
     * A set of useful static methods to deal with arrays; provide missing methods for older browsers.

     * @singleton
     * @markdown
     */
    (function() {

        var arrayPrototype = Array.prototype,
            slice = arrayPrototype.slice,
            supportsForEach = 'forEach' in arrayPrototype,
            supportsMap = 'map' in arrayPrototype,
            supportsIndexOf = 'indexOf' in arrayPrototype,
            supportsEvery = 'every' in arrayPrototype,
            supportsSome = 'some' in arrayPrototype,
            supportsFilter = 'filter' in arrayPrototype,
            supportsSort = function() {
                var a = [1,2,3,4,5].sort(function(){ return 0; });
                return a[0] === 1 && a[1] === 2 && a[2] === 3 && a[3] === 4 && a[4] === 5;
            }(),
            supportsSliceOnNodeList = true,
            ExtArray;
        try {
            // IE 6 - 8 will throw an error when using Array.prototype.slice on NodeList
            if (typeof document !== 'undefined') {
                slice.call(document.getElementsByTagName('body'));
            }
        } catch (e) {
            supportsSliceOnNodeList = false;
        }

        ExtArray = Ext.Array = {
            /*
             * Iterates an array or an iterable value and invoke the given callback function for each item.

        var countries = ['Vietnam', 'Singapore', 'United States', 'Russia'];

        Ext.Array.each(countries, function(name, index, countriesItSelf) {
            console.log(name);
        });

        var sum = function() {
            var sum = 0;

            Ext.Array.each(arguments, function(value) {
                sum += value;
            });

            return sum;
        };

        sum(1, 2, 3); // returns 6

             * The iteration can be stopped by returning false in the function callback.

        Ext.Array.each(countries, function(name, index, countriesItSelf) {
            if (name === 'Singapore') {
                return false; // break here
            }
        });

             * @param {Array/NodeList/Mixed} iterable The value to be iterated. If this
             * argument is not iterable, the callback function is called once.
             * @param {Function} fn The callback function. If it returns false, the iteration stops and this method returns
             * the current `index`. Arguments passed to this callback function are:

    - `item`: {Mixed} The item at the current `index` in the passed `array`
    - `index`: {Number} The current `index` within the `array`
    - `allItems`: {Array/NodeList/Mixed} The `array` passed as the first argument to `Ext.Array.each`

             * @param {Object} scope (Optional) The scope (`this` reference) in which the specified function is executed.
             * @param {Boolean} reverse (Optional) Reverse the iteration order (loop from the end to the beginning)
             * Defaults false
             * @return {Boolean} See description for the `fn` parameter.
             * @markdown
             */
            each: function(array, fn, scope, reverse) {
                array = ExtArray.from(array);

                var i,
                    ln = array.length;

                if (reverse !== true) {
                    for (i = 0; i < ln; i++) {
                        if (fn.call(scope || array[i], array[i], i, array) === false) {
                            return i;
                        }
                    }
                }
                else {
                    for (i = ln - 1; i > -1; i--) {
                        if (fn.call(scope || array[i], array[i], i, array) === false) {
                            return i;
                        }
                    }
                }

                return true;
            },

            /**
             * Iterates an array and invoke the given callback function for each item. Note that this will simply
             * delegate to the native Array.prototype.forEach method if supported.
             * It doesn't support stopping the iteration by returning false in the callback function like
             * {@link Ext.Array#each}. However, performance could be much better in modern browsers comparing with
             * {@link Ext.Array#each}
             *
             * @param {Array} array The array to iterate
             * @param {Function} fn The function callback, to be invoked these arguments:
             *
    - `item`: {Mixed} The item at the current `index` in the passed `array`
    - `index`: {Number} The current `index` within the `array`
    - `allItems`: {Array} The `array` itself which was passed as the first argument

             * @param {Object} scope (Optional) The execution scope (`this`) in which the specified function is executed.
             * @markdown
             */
            forEach: function(array, fn, scope) {
                if (supportsForEach) {
                    return array.forEach(fn, scope);
                }

                var i = 0,
                    ln = array.length;

                for (; i < ln; i++) {
                    fn.call(scope, array[i], i, array);
                }
            },

            /**
             * Get the index of the provided `item` in the given `array`, a supplement for the
             * missing arrayPrototype.indexOf in Internet Explorer.
             *
             * @param {Array} array The array to check
             * @param {Mixed} item The item to look for
             * @param {Number} from (Optional) The index at which to begin the search
             * @return {Number} The index of item in the array (or -1 if it is not found)
             * @markdown
             */
            indexOf: function(array, item, from) {
                if (supportsIndexOf) {
                    return array.indexOf(item, from);
                }

                var i, length = array.length;

                for (i = (from < 0) ? Math.max(0, length + from) : from || 0; i < length; i++) {
                    if (array[i] === item) {
                        return i;
                    }
                }

                return -1;
            },

            /**
             * Checks whether or not the given `array` contains the specified `item`
             *
             * @param {Array} array The array to check
             * @param {Mixed} item The item to look for
             * @return {Boolean} True if the array contains the item, false otherwise
             * @markdown
             */
            contains: function(array, item) {
                if (supportsIndexOf) {
                    return array.indexOf(item) !== -1;
                }

                var i, ln;

                for (i = 0, ln = array.length; i < ln; i++) {
                    if (array[i] === item) {
                        return true;
                    }
                }

                return false;
            },

            /**
             * Converts any iterable (numeric indices and a length property) into a true array.

    function test() {
        var args = Ext.Array.toArray(arguments),
            fromSecondToLastArgs = Ext.Array.toArray(arguments, 1);

        alert(args.join(' '));
        alert(fromSecondToLastArgs.join(' '));
    }

    test('just', 'testing', 'here'); // alerts 'just testing here';
                                     // alerts 'testing here';

    Ext.Array.toArray(document.getElementsByTagName('div')); // will convert the NodeList into an array
    Ext.Array.toArray('splitted'); // returns ['s', 'p', 'l', 'i', 't', 't', 'e', 'd']
    Ext.Array.toArray('splitted', 0, 3); // returns ['s', 'p', 'l', 'i']

             * @param {Mixed} iterable the iterable object to be turned into a true Array.
             * @param {Number} start (Optional) a zero-based index that specifies the start of extraction. Defaults to 0
             * @param {Number} end (Optional) a zero-based index that specifies the end of extraction. Defaults to the last
             * index of the iterable value
             * @return {Array} array
             * @markdown
             */
            toArray: function(iterable, start, end){
                if (!iterable || !iterable.length) {
                    return [];
                }

                if (typeof iterable === 'string') {
                    iterable = iterable.split('');
                }

                if (supportsSliceOnNodeList) {
                    return slice.call(iterable, start || 0, end || iterable.length);
                }

                var array = [],
                    i;

                start = start || 0;
                end = end ? ((end < 0) ? iterable.length + end : end) : iterable.length;

                for (i = start; i < end; i++) {
                    array.push(iterable[i]);
                }

                return array;
            },

            /**
             * Plucks the value of a property from each item in the Array. Example:
             *
        Ext.Array.pluck(Ext.query("p"), "className"); // [el1.className, el2.className, ..., elN.className]

             * @param {Array|NodeList} array The Array of items to pluck the value from.
             * @param {String} propertyName The property name to pluck from each element.
             * @return {Array} The value from each item in the Array.
             */
            pluck: function(array, propertyName) {
                var ret = [],
                    i, ln, item;

                for (i = 0, ln = array.length; i < ln; i++) {
                    item = array[i];

                    ret.push(item[propertyName]);
                }

                return ret;
            },

            /**
             * Creates a new array with the results of calling a provided function on every element in this array.
             * @param {Array} array
             * @param {Function} fn Callback function for each item
             * @param {Object} scope Callback function scope
             * @return {Array} results
             */
            map: function(array, fn, scope) {
                if (supportsMap) {
                    return array.map(fn, scope);
                }

                var results = [],
                    i = 0,
                    len = array.length;

                for (; i < len; i++) {
                    results[i] = fn.call(scope, array[i], i, array);
                }

                return results;
            },

            /**
             * Executes the specified function for each array element until the function returns a falsy value.
             * If such an item is found, the function will return false immediately.
             * Otherwise, it will return true.
             *
             * @param {Array} array
             * @param {Function} fn Callback function for each item
             * @param {Object} scope Callback function scope
             * @return {Boolean} True if no false value is returned by the callback function.
             */
            every: function(array, fn, scope) {
                //<debug>
                if (!fn) {
                    Ext.Error.raise('Ext.Array.every must have a callback function passed as second argument.');
                }
                //</debug>
                if (supportsEvery) {
                    return array.every(fn, scope);
                }

                var i = 0,
                    ln = array.length;

                for (; i < ln; ++i) {
                    if (!fn.call(scope, array[i], i, array)) {
                        return false;
                    }
                }

                return true;
            },

            /**
             * Executes the specified function for each array element until the function returns a truthy value.
             * If such an item is found, the function will return true immediately. Otherwise, it will return false.
             *
             * @param {Array} array
             * @param {Function} fn Callback function for each item
             * @param {Object} scope Callback function scope
             * @return {Boolean} True if the callback function returns a truthy value.
             */
            some: function(array, fn, scope) {
                //<debug>
                if (!fn) {
                    Ext.Error.raise('Ext.Array.some must have a callback function passed as second argument.');
                }
                //</debug>
                if (supportsSome) {
                    return array.some(fn, scope);
                }

                var i = 0,
                    ln = array.length;

                for (; i < ln; ++i) {
                    if (fn.call(scope, array[i], i, array)) {
                        return true;
                    }
                }

                return false;
            },

            /**
             * Filter through an array and remove empty item as defined in {@link Ext#isEmpty Ext.isEmpty}
             *
             * @see Ext.Array.filter
             * @param {Array} array
             * @return {Array} results
             */
            clean: function(array) {
                var results = [],
                    i = 0,
                    ln = array.length,
                    item;

                for (; i < ln; i++) {
                    item = array[i];

                    if (!Ext.isEmpty(item)) {
                        results.push(item);
                    }
                }

                return results;
            },

            /**
             * Returns a new array with unique items
             *
             * @param {Array} array
             * @return {Array} results
             */
            unique: function(array) {
                var clone = [],
                    i = 0,
                    ln = array.length,
                    item;

                for (; i < ln; i++) {
                    item = array[i];

                    if (ExtArray.indexOf(clone, item) === -1) {
                        clone.push(item);
                    }
                }

                return clone;
            },

            /**
             * Creates a new array with all of the elements of this array for which
             * the provided filtering function returns true.
             * @param {Array} array
             * @param {Function} fn Callback function for each item
             * @param {Object} scope Callback function scope
             * @return {Array} results
             */
            filter: function(array, fn, scope) {
                if (supportsFilter) {
                    return array.filter(fn, scope);
                }

                var results = [],
                    i = 0,
                    ln = array.length;

                for (; i < ln; i++) {
                    if (fn.call(scope, array[i], i, array)) {
                        results.push(array[i]);
                    }
                }

                return results;
            },

            /**
             * Converts a value to an array if it's not already an array; returns:
             *
             * - An empty array if given value is `undefined` or `null`
             * - Itself if given value is already an array
             * - An array copy if given value is {@link Ext#isIterable iterable} (arguments, NodeList and alike)
             * - An array with one item which is the given value, otherwise
             *
             * @param {Array/Mixed} value The value to convert to an array if it's not already is an array
             * @param {Boolean} (Optional) newReference True to clone the given array and return a new reference if necessary,
             * defaults to false
             * @return {Array} array
             * @markdown
             */
            from: function(value, newReference) {
                if (value === undefined || value === null) {
                    return [];
                }

                if (Ext.isArray(value)) {
                    return (newReference) ? slice.call(value) : value;
                }

                if (value && value.length !== undefined && typeof value !== 'string') {
                    return Ext.toArray(value);
                }

                return [value];
            },

            /**
             * Removes the specified item from the array if it exists
             *
             * @param {Array} array The array
             * @param {Mixed} item The item to remove
             * @return {Array} The passed array itself
             */
            remove: function(array, item) {
                var index = ExtArray.indexOf(array, item);

                if (index !== -1) {
                    array.splice(index, 1);
                }

                return array;
            },

            /**
             * Push an item into the array only if the array doesn't contain it yet
             *
             * @param {Array} array The array
             * @param {Mixed} item The item to include
             * @return {Array} The passed array itself
             */
            include: function(array, item) {
                if (!ExtArray.contains(array, item)) {
                    array.push(item);
                }
            },

            /**
             * Clone a flat array without referencing the previous one. Note that this is different
             * from Ext.clone since it doesn't handle recursive cloning. It's simply a convenient, easy-to-remember method
             * for Array.prototype.slice.call(array)
             *
             * @param {Array} array The array
             * @return {Array} The clone array
             */
            clone: function(array) {
                return slice.call(array);
            },

            /**
             * Merge multiple arrays into one with unique items. Alias to {@link Ext.Array#union}.
             *
             * @param {Array} array,...
             * @return {Array} merged
             */
            merge: function() {
                var args = slice.call(arguments),
                    array = [],
                    i, ln;

                for (i = 0, ln = args.length; i < ln; i++) {
                    array = array.concat(args[i]);
                }

                return ExtArray.unique(array);
            },

            /**
             * Merge multiple arrays into one with unique items that exist in all of the arrays.
             *
             * @param {Array} array,...
             * @return {Array} intersect
             */
            intersect: function() {
                var intersect = [],
                    arrays = slice.call(arguments),
                    i, j, k, minArray, array, x, y, ln, arraysLn, arrayLn;

                if (!arrays.length) {
                    return intersect;
                }

                // Find the smallest array
                for (i = x = 0,ln = arrays.length; i < ln,array = arrays[i]; i++) {
                    if (!minArray || array.length < minArray.length) {
                        minArray = array;
                        x = i;
                    }
                }

                minArray = Ext.Array.unique(minArray);
                arrays.splice(x, 1);

                // Use the smallest unique'd array as the anchor loop. If the other array(s) do contain
                // an item in the small array, we're likely to find it before reaching the end
                // of the inner loop and can terminate the search early.
                for (i = 0,ln = minArray.length; i < ln,x = minArray[i]; i++) {
                    var count = 0;

                    for (j = 0,arraysLn = arrays.length; j < arraysLn,array = arrays[j]; j++) {
                        for (k = 0,arrayLn = array.length; k < arrayLn,y = array[k]; k++) {
                            if (x === y) {
                                count++;
                                break;
                            }
                        }
                    }

                    if (count === arraysLn) {
                        intersect.push(x);
                    }
                }

                return intersect;
            },

            /**
             * Perform a set difference A-B by subtracting all items in array B from array A.
             *
             * @param {Array} array A
             * @param {Array} array B
             * @return {Array} difference
             */
            difference: function(arrayA, arrayB) {
                var clone = slice.call(arrayA),
                    ln = clone.length,
                    i, j, lnB;

                for (i = 0,lnB = arrayB.length; i < lnB; i++) {
                    for (j = 0; j < ln; j++) {
                        if (clone[j] === arrayB[i]) {
                            clone.splice(j, 1);
                            j--;
                            ln--;
                        }
                    }
                }

                return clone;
            },

            /**
             * Sorts the elements of an Array.
             * By default, this method sorts the elements alphabetically and ascending.
             *
             * @param {Array} array The array to sort.
             * @param {Function} sortFn (optional) The comparison function.
             * @return {Array} The sorted array.
             */
            sort: function(array, sortFn) {
                if (supportsSort) {
                    if (sortFn) {
                        return array.sort(sortFn);
                    } else {
                        return array.sort();
                    }
                }

                var length = array.length,
                    i = 0,
                    comparison,
                    j, min, tmp;

                for (; i < length; i++) {
                    min = i;
                    for (j = i + 1; j < length; j++) {
                        if (sortFn) {
                            comparison = sortFn(array[j], array[min]);
                            if (comparison < 0) {
                                min = j;
                            }
                        } else if (array[j] < array[min]) {
                            min = j;
                        }
                    }
                    if (min !== i) {
                        tmp = array[i];
                        array[i] = array[min];
                        array[min] = tmp;
                    }
                }

                return array;
            },

            /**
             * Recursively flattens into 1-d Array. Injects Arrays inline.
             * @param {Array} array The array to flatten
             * @return {Array} The new, flattened array.
             */
            flatten: function(array) {
                var worker = [];

                function rFlatten(a) {
                    var i, ln, v;

                    for (i = 0, ln = a.length; i < ln; i++) {
                        v = a[i];

                        if (Ext.isArray(v)) {
                            rFlatten(v);
                        } else {
                            worker.push(v);
                        }
                    }

                    return worker;
                }

                return rFlatten(array);
            },

            /**
             * Returns the minimum value in the Array.
             * @param {Array|NodeList} array The Array from which to select the minimum value.
             * @param {Function} comparisonFn (optional) a function to perform the comparision which determines minimization.
             *                   If omitted the "<" operator will be used. Note: gt = 1; eq = 0; lt = -1
             * @return {Mixed} minValue The minimum value
             */
            min: function(array, comparisonFn) {
                var min = array[0],
                    i, ln, item;

                for (i = 0, ln = array.length; i < ln; i++) {
                    item = array[i];

                    if (comparisonFn) {
                        if (comparisonFn(min, item) === 1) {
                            min = item;
                        }
                    }
                    else {
                        if (item < min) {
                            min = item;
                        }
                    }
                }

                return min;
            },

            /**
             * Returns the maximum value in the Array
             * @param {Array|NodeList} array The Array from which to select the maximum value.
             * @param {Function} comparisonFn (optional) a function to perform the comparision which determines maximization.
             *                   If omitted the ">" operator will be used. Note: gt = 1; eq = 0; lt = -1
             * @return {Mixed} maxValue The maximum value
             */
            max: function(array, comparisonFn) {
                var max = array[0],
                    i, ln, item;

                for (i = 0, ln = array.length; i < ln; i++) {
                    item = array[i];

                    if (comparisonFn) {
                        if (comparisonFn(max, item) === -1) {
                            max = item;
                        }
                    }
                    else {
                        if (item > max) {
                            max = item;
                        }
                    }
                }

                return max;
            },

            /**
             * Calculates the mean of all items in the array
             * @param {Array} array The Array to calculate the mean value of.
             * @return {Number} The mean.
             */
            mean: function(array) {
                return array.length > 0 ? ExtArray.sum(array) / array.length : undefined;
            },

            /**
             * Calculates the sum of all items in the given array
             * @param {Array} array The Array to calculate the sum value of.
             * @return {Number} The sum.
             */
            sum: function(array) {
                var sum = 0,
                    i, ln, item;

                for (i = 0,ln = array.length; i < ln; i++) {
                    item = array[i];

                    sum += item;
                }

                return sum;
            }

        };

        /**
         * Convenient alias to {@link Ext.Array#each}
         * @member Ext
         * @method each
         */
        Ext.each = Ext.Array.each;

        /**
         * Alias to {@link Ext.Array#merge}.
         * @member Ext.Array
         * @method union
         */
        Ext.Array.union = Ext.Array.merge;

        /**
         * Old alias to {@link Ext.Array#min}
         * @deprecated 4.0.0 Use {@link Ext.Array#min} instead
         * @member Ext
         * @method min
         */
        Ext.min = Ext.Array.min;

        /**
         * Old alias to {@link Ext.Array#max}
         * @deprecated 4.0.0 Use {@link Ext.Array#max} instead
         * @member Ext
         * @method max
         */
        Ext.max = Ext.Array.max;

        /**
         * Old alias to {@link Ext.Array#sum}
         * @deprecated 4.0.0 Use {@link Ext.Array#sum} instead
         * @member Ext
         * @method sum
         */
        Ext.sum = Ext.Array.sum;

        /**
         * Old alias to {@link Ext.Array#mean}
         * @deprecated 4.0.0 Use {@link Ext.Array#mean} instead
         * @member Ext
         * @method mean
         */
        Ext.mean = Ext.Array.mean;

        /**
         * Old alias to {@link Ext.Array#flatten}
         * @deprecated 4.0.0 Use {@link Ext.Array#flatten} instead
         * @member Ext
         * @method flatten
         */
        Ext.flatten = Ext.Array.flatten;

        /**
         * Old alias to {@link Ext.Array#clean Ext.Array.clean}
         * @deprecated 4.0.0 Use {@link Ext.Array.clean} instead
         * @member Ext
         * @method clean
         */
        Ext.clean = Ext.Array.clean;

        /**
         * Old alias to {@link Ext.Array#unique Ext.Array.unique}
         * @deprecated 4.0.0 Use {@link Ext.Array.unique} instead
         * @member Ext
         * @method unique
         */
        Ext.unique = Ext.Array.unique;

        /**
         * Old alias to {@link Ext.Array#pluck Ext.Array.pluck}
         * @deprecated 4.0.0 Use {@link Ext.Array#pluck Ext.Array.pluck} instead
         * @member Ext
         * @method pluck
         */
        Ext.pluck = Ext.Array.pluck;

        /**
         * Convenient alias to {@link Ext.Array#toArray Ext.Array.toArray}
         * @param {Iterable} the iterable object to be turned into a true Array.
         * @member Ext
         * @method toArray
         * @return {Array} array
         */
        Ext.toArray = function() {
            return ExtArray.toArray.apply(ExtArray, arguments);
        }
    })();