xmap-js-rubaxa

/**
 * Реализовать свой Map
 * @constructor
 */
function XMap() {
    const buf = Object.create(null);

    this.set = (key, value) => {
        buf[key] = value;
    };

    this.get = (key) => {
        return buf[key];
    };

    this.has = (key) => {
        return buf[key] !== undefined;
    };

    this.remove = (key) => {
        delete buf[key];
    };
}

// Проверка
const map = new XMap();
const objKey = {foo: true};

map.set(123, 'ok');
map.set(objKey, 'fail');
map.has(objKey) && map.set(objKey, 'wow');

console.log(map.get(123)); // "ok"
console.log(map.get(objKey)); // "wow"

map.remove(123);
console.log(map.has(123)); // false

map.has('toString');