//myForeach    数组每个元素都执行一次回调函数
// (typeof Array.prototype.forEach==="undefined")&&(Array.prototype.forEach = function(callback){
//     for(var i = 0 ; i < this.length ; i++){
//         var element = this[i];
//         callback(element,i,this);
//     }
// });
(Array.prototype.mforEach = function (callback, thisArg) {
    var T, k;
    if (this == null) {
        throw new TypeError("this is null or not defined");
    }
    var O = Object(this);
    var len = O.length >>> 0;
    if (typeof callback !== "function") {
        throw new TypeError(callback + " is not a function");
    }
    if (arguments.length > 1) {
        T = thisArg;
    }
    k = 0;
    while (k < len) {
        var kValue;
        if (k in O) {
            kValue = O[k];
            callback.call(T, kValue, k, O);
        }
        k++;
    }
});
//myEvery    检测数值元素的每个元素是否都符合条件
(typeof Array.prototype.every === "undefined") && (Array.prototype.every = function (callback) {
    for (var i = 0; i < this.length; i++) {
        var item = this[i];
        if (!callback(item, i, this)) {
            return false;
        }
    }
    return true;
});
//mySome    检测数组元素中是否有元素符合指定条件
(typeof Array.prototype.some === "undefined") && (Array.prototype.some = function (callback) {
    for (var i = 0; i < this.length; i++) {
        var item = this[i];
        if (callback(item, i, this)) {
            return true;
        }

    }
    return false;
});
//myFilter    检测数值元素，并返回符合条件所有元素的数组
(typeof Array.prototype.filter === "undefined") && (Array.prototype.filter = function (callback) {
    var arr = [];
    var temp = 0;
    for (var i = 0; i < this.length; i++) {
        var item = this[i];
        if (callback(item, i, this)) {
            arr[temp] = item;
            temp++;
        }
    }
    return arr;
});
//myReduce    将数组元素计算为一个值（从左到右）
(typeof Array.prototype.reduce === "undefined") && (Array.prototype.reduce = function (callback, initialValue) {
    var num = 0;
    var total;
    if (initialValue !== undefined) {
        total = initialValue;
    } else {
        total = this[0];
        num = 1;
    }

    for (var i = num; i < this.length; i++) {
        var item = this[i];
        total = callback(total, item, i, this);

    }
    return total;
});
// (typeof Array.prototype.push === "undefined") && (Array.prototype.push=function () {
//     for (var i=0;i<arguments.length;i++){
//         this[this.length]=arguments[i]
//     }
//     return this.length;
// });
// (typeof Array.prototype.map === "undefined") && (Array.prototype.map = function(fn) {
//     if (typeof fn !== "function") {
//         throw new TypeError(fn+"is not a function");
//     }
//     let newArr = [];
//     for (let i = 0; i < this.length; i++) {
//         newArr.push(fn(this[i]));
//     }
//     return newArr;
// });

// ie8 兼容bind
!Function.prototype.bind && (Function.prototype.bind = function (oThis) {
    if (typeof this !== "function") {
        throw new TypeError("Function.prototype.bind - what is trying to be bound is not callable");
    }
    var aArgs = Array.prototype.slice.call(arguments, 1),
        fToBind = this,
        fNOP = function () {},
        fBound = function () {
            return fToBind.apply(this instanceof fNOP && oThis ? this : oThis, aArgs.concat(Array.prototype.slice.call(arguments)));
        };
    fNOP.prototype = this.prototype;
    fBound.prototype = new fNOP();
    return fBound;
});