// Classic OOP example using structural typing for implicit
// polymorphism
type Vehicle = {
  color: string;
};

function drive(v: Vehicle, distance: number) {
  console.log(`driving ${distance} units in a ${v.color} vehicle`);
};

// Straightforward instantiation and use
const vehicle: Vehicle = {
  color: "purple",
};

drive(vehicle, 12);

// Objects with correct "structure" are valid
const obj = {
  color: "blue",
};

drive(obj, 10);

// Objects with correct "structure" _and extra propertes_ are valid
const obj2 = {
  color: "green",
  hasLeatherSeats: true,
};

drive(obj2, 10);

// Now for a another type
// Note we do not say "extends Vehicle" anywhere
type Truck = {
  color: string;
  carryingCapacity: number;
};

function carry(t: Truck, load: number) {
  if (load > t.carryingCapacity) {
    console.log(`failed to carry ${load} units in a ${t.color} truck`);
  } else {
    console.log(`carrying ${load} units in a ${t.color} truck`);
  }
};

const truck: Truck = {
  color: "red",
  carryingCapacity: 8,
};

carry(truck, 7);

// Is a Truck a Vehicle?
// Uncomment to find out
// drive(truck, 15);

// Is a Vehicle a Truck?
// Uncomment to find out
// carry(vehicle, 10);