Classes and inheritance

A class is a template for objects that share the same shape and behavior. constructor(...) runs once when you create an instance with new - it's where you set the instance's own properties with this.property = value. Methods defined in the class body are shared by every instance instead of copied onto each one.

class Dog extends Animal builds a subclass: Dog gets every method Animal has for free, and only needs to define what's different. Overriding a method - writing a same-named method in the subclass - replaces the parent's version for instances of the subclass, without touching how Animal itself behaves.

Your task: write class Animal with a constructor that stores name, and a method speak() returning "<name> makes a sound". Then write class Dog, extending Animal, that overrides speak() to return "<name> barks" instead.

You'll practice:

Writing a constructor and a method on a class
Extending a class and overriding one of its methods

// Write class Animal: constructor(name) stores this.name;
// speak() returns "<name> makes a sound".
class Animal {

}

// Write class Dog extending Animal: override speak() to return "<name> barks".
class Dog extends Animal {

}