javascript-call和javascript-apply的用法，实现javascript-bind

function.prototype.bind = function () {
    var self = this;  //保存原函数
    var args = [].slice.call(arguments);
    var context = args.shift();
    return function () {
        var argsArr = [].slice.call(arguments);
        return self.apply(context, args.concat(argsArr));
    }
}
var bindTest = function (age, grade) {
    console.log(this.name);
    console.log([age, grade]);
}.bind({name: 'Jack'}, 22);
bindTest(95.0);