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true call polyfil(without spread/rest operators); bonus: apply & bind polyfills

I've been practicing call, apply, bind polyfills and suddenly realized that it's not really a polyfill if I use spread/rest operators, can't figure out how to pass arguments in call without it, any ideas folks?

//my attempt to write call polyfil without spread operator
//but it doesn't work
Function.prototype.call = function () {
  const obj = arguments[0];
  obj.fn = this;
  const args = Array(arguments).slice(1).reverse();
  while (args.length) {
    obj.fn.arguments.push(args.pop());
  }

  //obj.fn.arguments = Array(arguments).slice(1);
  obj.fn();
};

// that one works, but it uses spread operator
Function.prototype.call = function (obj, ...args) {
  obj.fn = this;
  obj.fn(...args);
};

Function.prototype.apply = function (obj, args) {
  obj.fn = this;
  obj.fn(...args);
};

Function.prototype.myBind = function (obj, ...args) {
  const fn = this;

  return function (...newArgs) {
    const allArgs = [...args, ...newArgs];
    fn.call(obj, ...allArgs);
    //fn.apply(obj, allArgs);
  };
};

let obj = {
  name: "Jack",
};

let myFunc = function (id, city) {
  console.log(`${this.name}, ${id}, ${city}`); 
};

let newFunc = myFunc.myBind(obj, "a_random_id");
newFunc("New York"); // Jack, a_random_id, New York
almost 3 years ago · Juan Pablo Isaza
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