let obj = {
a:1,
b:2
}
Function.prototype.myApply = function(content,arr){
console.log(‘myApply‘);
let _this = this;
let sy = Symbol();
content[sy] = _this;
return content[sy](...arr);
}
function add(c,d,e){
console.log(this.a + this.b + c + d + e);
}
add.myApply(obj,[2,4,1]);