Tell us about the inheritance chain of classes in the Swift programming language.

Classes in Swift support single inheritance. Each class inherits from one parent class, forming a hierarchy. The inheritance chain starts with a base class that inherits from nothing and extends downward through child classes.

Inheritance properties:

• Overriding: A child class can override the implementation of methods, properties, and subscripts of the parent class. The keyword override is used.
• Preventing Overrides: You can prevent a member from being overridden by marking it with the keyword final. The entire class can also be declared as final.
• Access to the parent class: A child class can access the implemented members of the parent class using the keyword super. This is useful for calling the parent method's implementation or accessing the parent property.

Example:

// Base class
class Vehicle {
    var currentSpeed = 0.0

    func makeNoise() {
        // Empty implementation
    }
}

// Child class inheriting from Vehicle
class Car: Vehicle {
    var numberOfDoors = 4

    // Overriding the makeNoise method
    override func makeNoise() {
        print("Beep beep")
    }
}

// Child class inheriting from Car
class ElectricCar: Car {
    var batteryLevel = 100.0

    // Adding a new property
    let isElectric = true

    // Overriding the property from the base class
    override internal var currentSpeed: Double {
        didSet {
            if currentSpeed > 0 {
                print("Electric car is moving")
            }
        }
    }
}

In this example:

• Vehicle is the base class.
• Car inherits from Vehicle. It adds the property numberOfDoors and overrides the makeNoise method.
• ElectricCar inherits from Car. It adds the property batteryLevel, the constant isElectric, and overrides the currentSpeed property.

Inheritance chain: Vehicle -> Car -> ElectricCar. Each class in this chain has access to all open (or accessible in another context) members of the classes higher in the hierarchy.