Write your pollyfill of Map, Call , Apply, Bind without help of es6

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Map Function:-

Array.prototype.myMap = function (callback) {
const newArray = [];
for(const item of this) {
newArray.push(callback(item));
}
return newArray;
};

Call Function:-

Function.prototype.myCall = function(obj) {
obj = obj || global;
var id = "00" + Math.random();
while (obj.hasOwnProperty(id)) {
id = "00" + Math.random();
}
obj[id] = this;
let arg=[];
for(let i=1;i<arguments.length;i++){
arg.push("arguments[" + i + "]");
}
result= eval("obj[id]("+arg+")");
delete obj[id];
return result;
}

Apply function:-

Function.prototype.myApply = function(obj, argArr) {
obj = obj || global;
var id = "00" + Math.random();
while (obj.hasOwnProperty(id)) {
id = "00" + Math.random();
}
obj[id] = this;
let arg=[];
let result
if(!argArr){
result= obj[id].fn();
}
else{
for(let i=0;i<argArr.length;i++){
arg.push("argArr[" + i + "]");
}
result= eval("obj[id]("+arg+")");
delete obj[id];
}
return result;

}

Bind function:-

Function.prototype.myBind2= function(){
let obj1= this;
const obj= Array.prototype.slice.call(arguments,0,1);
const arg= Array.prototype.slice.call(arguments,1);
return function(){
const arg2= Array.prototype.slice.call(arguments);
obj1.apply(obj[0],Array.prototype.concat(arg, arg2));
}

Another solution: we can pass object as argument of function

Function.prototype.myBind2 = function(obj) {
let fn = this;
const arg = Array.prototype.slice.call(arguments, 1);
return function() {
const arg2 = Array.prototype.slice.call(arguments);
fn.apply(obj, Array.prototype.concat(arg, arg2));
}

Another solution using es6 (spread operator):-

Function.prototype.myBind= function(obj,...arg){
let obj1= this;
return function(...arg2){
obj1.apply(obj, [...arg, ...arg2]);
}
}