Object-Oriented Programming

1import std.io;
2
3// Interface contract
4interface Greeter {
5    fn greet() -> void;
6}
7
8// Base class with virtual method
9class Person : Greeter {
10    protected string name;
11    
12    public Person(string name) {
13        this.name = name;
14    }
15    
16    public virtual fn greet() -> void {
17        println("Hello, I am ${this.name}");
18    }
19}
20
21// Single inheritance & method override
22class Employee : Person {
23    private string role;
24    
25    public Employee(string name, string role) : super(name) {
26        this.role = role;
27    }
28    
29    public override fn greet() -> void {
30        println("Greetings, I am ${this.name}, working as ${this.role}");
31    }
32}
33
34// Lightweight value-type struct (stack allocated)
35struct Point {
36    int x;
37    int y;
38}
39
40fn main() -> void {
41    Person p = new Employee("Sarah", "Systems Engineer");
42    p.greet();
43    
44    Point pt = Point(10, 20);
45    println("Point: (${pt.x}, ${pt.y})");
46}