javascript中的add(1)(2)(3)(4)是怎么实现的
javascript中的add(1)(2)(3)(4)是怎么实现的?实现如下:
1 var fn = function(a){ 2 let sum = a; 3 let tempFn = function(b){ 4 sum += b; //数据处理逻辑 5 return tempFn; 6 } 7 tempFn.getVal = function (){ 8 return sum; 9 } 10 return tempFn; 11 } 12 13 fn(1).getVal(); //1 14 fn(1)(2)(3).getVal(); //6 15 fn(1)(2)(3)(4)(5)(6)(7)...