The ES2015 Map class
ECMAScript 2015 introduced a Map class as part of the JavaScript API. We developed our Dictionary class based on the ES2015Â Map class.
Note
You can take a look at the details of the ECMAScript 2015 Map class implementation at: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map (or http://goo.gl/dm8VP6).
Let's learn how we can use the native Map class, as well. Let's use the same examples we used to test our Dictionary class:
const map = new Map();
map.set('Gandalf', 'gandalf@email.com');
map.set('John', 'johnsnow@email.com');
map.set('Tyrion', 'tyrion@email.com');
console.log(map.has('Gandalf')); // true
console.log(map.size); // 3
console.log(map.keys()); // MapIterator {"Gandalf", "John", "Tyrion"}
console.log(map.values()); // MapIterator {"gandalf@email.com", "johnsnow@email.com", "tyrion@email.com"}
console.log(map.get('Tyrion')); // tyrion@email.com The difference between our Dictionary class and the ES2015Â Map class is that the...
