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.

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')); // trueconsole.log(map.size); // 3console.log(map.keys()); // MapIterator {"Gandalf", "John", "Tyrion"} ...

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