The ES2015 Map class
ECMAScript 2015 introduced a Map
class as part of the JavaScript API. We developed our Dictionary
class based on the ES2015 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 ES2015 Map
class is that the...