Inheritance

Inheritance is one of the major features of OOP. Aussom supports inheritance for both Aussom and external classes. Inheritance lets you define a super class and then create sub classes that inherit members and functions from the parent class. Lets start with a simple example.

In the example below, we have a super class 'animal' and a sub class of 'dog'. Notice in the class definition of dog that there is a colon and a reference to animal after it. This tells Aussom that dog is a subclass of animal. This will make all members and functions of animal available to dog.

// Super class.
class animal {
	// Animal actions
	public run() { sys.println("running ..."); }
	public eat() { sys.println("eating ..."); }
	public sleep() { sys.println("sleeping ..."); }
}

// Subclass of animal.
class dog : animal {
	public bark() { sys.println("woof! ..."); }
	public wag() { sys.println("wagging tail ..."); }
}

// So we can then do this.
myDog = new dog();
myDog.run();		// Defined in animal class.
myDog.eat();		// Defined in animal class.
myDog.bark();		// Defined in dog class.

The above example is great, but in Aussom we can inherit from multiple classes. The example below show dog inheriting from class animal and carnivore.

// Super class carnivore.
class carnivore {
	public hunt() { sys.println("you don't see me ..."); }
}

// Subclass of animal and carnivore.
class dog : animal, carnivore {
	public bark() { sys.println("woof! ..."); }
	public wag() { sys.println("wagging tail ..."); }
}

// So we can do this then.
myDog = new dog();
myDog.run();		// Defined in animal class.
myDog.hunt();		// Defined in carnivore class.
myDog.bark();		// Defined in dog class.

Note: When inheriting from an external class, you may only inherit from that class at this time. More on that in the external classes and functions section.