Adding and deleting items from WeakSet

Now, we'll take a look at the corresponding weak data structure, WeakSet. In this recipe, we'll look at how to add and delete items from a WeakSet, using the respective instance methods, and at some restrictions on membership.

Getting ready

This recipe assumes that you already have a workspace that allows you to create and run ES modules in your browser. If you don't, refer to the first two chapters.

How to do it...

1. Open your command-line application, and navigate to your workspace.
2. Create a new folder named 12-03-add-remove-from-weak-set.
3. Copy or create an index.html that loads and runs a main function from main.js.
4. Create a main.js file that defines a new class named Rocket that takes a constructor argument name and assigns it to an instance property:

// main.js 
class Rocket { 
  constructor(name) { 
    this.name = name; 
  } 
}    

5. Create a main function with some Rocket instances and a WeakMap instance. Add and remove the instances from the set:

// main...