Implement instanceof

/ / ideas:
// 1. If the instance type passed is not a reference type, return false
// 2. Get the prototype of the instance and check if it === constructor prototype
// 3. If not, exit loop until null is found and return false


function isInstanceof(instance, Constructor) {
  if (typeofinstance ! = ='function'
      && (typeofinstance ! = ='object' || typeof instance === null)) {return false }

  let proto = Object.getPrototypeOf(instance);

  while (true) {
    if (proto === null) {
      return false
    }
    if (proto === Constructor.prototype) {
      return true
    }
    proto = Object.getPrototypeOf(proto); }}function Animal(name) { this.name = name }
function Cat(name) { Animal.call(this, name) }
Cat.prototype = Object.create(Animal.prototype);
Cat.prototype.constructor = Cat;

const cat = new Cat('kimi');
console.log(isInstanceof(cat, Cat)); // true
console.log(isInstanceof(cat, Animal)); // true
console.log(isInstanceof(cat, Object)); // true
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