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Prototypal Inheritance

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So... I tricked you a bit. Classes are actually a fairly new addition to JavaScript. See, they're not the underlying mechanism for inheritance - that's actually prototypes. Classes are just syntactic sugar for prototypes.

Every object in JavaScript has a prototype. When an object "inherits" from another object, it's really that its parent is marked as its "prototype". It's called prototypal inheritance. The built-in Object.create() method creates a new object with its prototype set to the given object.

const pureTitan = {
  // (define a parent object / prototype)
  name: "Eren's mom",
  speak(msg) {
    console.log("*titan noises*");
  },
};
pureTitan.speak();
// *titan noises*

const beastTitan = Object.create(pureTitan); // (define a child)

console.log(beastTitan.name); // (accessing .name from pureTitan)
// Eren's mom

beastTitan.name = "Zeke";
beastTitan.speak = function () {
  console.log(`${this.name} says, "I'm the Beast Titan"`);
};

beastTitan.speak();
// Zeke says, "I'm the Beast Titan"

Assignment

Textio needs a new notification system that uses a new subclass of notification that can both:

send to a single user (regular notifications already do this)
broadcast messages to all users (specific to this new subclass)

Use Object.create to create a new systemNotification object that inherits its prototype from notification.
Write a new method for systemNotification called broadcast that takes a single message string as input and returns:

Broadcast to all users: MESSAGE_GOES_HERE

Where "MESSAGE_GOES_HERE" is the given message string.