小技巧

//toString机制
function add(number1){
    var sum = number1;
    var app = function(number2){
        sum += number2;
        return app;
    };
    app.toString = function(){
        return sum;
    }
    return app;
}


alert(add(1)); // 1
console.log(add(1)(2)); // 3
console.log(add(1)(2)(3)); // 6
console.log(add(1)(2)(3)(4)); // 10

 //柯里化函数
function sum(x){
    function f(y){
        return sum(x+y);
    }
    f.toString = f.valueOf = function(){
        return x;
    };
    return f;
}
sum(1)(2)(3)
alert( (1) )

//不用循环打印    
function print(str,number){
            var arr = new Array( (number || 0) + 1 );
            var str = arr.join(str);
            alert(str)    
    }
        print("helloword ",10);