Example for generic class in typescript

truck.ts

class Person {
	name: string
	age: number
	constructor(name: string, age: number) {
		this.name = name;
		this.age = age;
	}
}
class Fruit {
	ripe: boolean;
	expiry: string;
	constructor(ripe: boolean, expiry: string) {
		this.ripe = ripe;
		this.expiry = expiry;
	}
}

class Vehicle {
	private wheels: number;
	private engine: 'Petrol' | 'Diesel';
	private driver: Person;
	getWheels() {
		return this.wheels;
	}
	setWheels(wheels: number) {
		this.wheels = wheels;
	}
	getEngine() {
		return this.engine;
	}
	setEngine(engine: 'Petrol' | 'Diesel') {
		this.engine = engine;
	}
	getDriver() {
		return this.driver;
	}
	setDriver(driver: Person) {
		this.driver = driver;
	}
}
class Truck<T> extends Vehicle {
	private load: T;
	getLoad() {
		return this.load
	}
	setLoad(load: T) {
		this.load = load;
	}
	hasCarriage() {
		return true;
	}
}
class TruckCarrier extends Truck<TruckCarrier>{
	hasRefregiration() {
		return false;
	}
	// ... other methods
}
class FruitsCarrier extends Truck<Fruit>{
	hasRefregiration() {
		return true;
	}
	// ... other methods
}
let fruitsCarriage: FruitsCarrier = new FruitsCarrier();
console.log('Fruit loaded')
fruitsCarriage.setLoad(new Fruit(true, 'July'))

// Async Transport .......
console.log('Fruit Transported')


// Checking cargo by fruit vendor (reciever)
if (fruitsCarriage.getLoad().ripe) {
	// since fruit carriage load type was fruits, the property of fruit ripe was accessible here
	console.log('Fruits are ripen')
	// do stuff if ripe
}


let truckCarriage: TruckCarrier = new TruckCarrier();

console.log('Truck loaded with another truck')
truckCarriage.setLoad(new TruckCarrier())


// Async Transport .......
console.log('Truck Transported')


// checking cargo by Truck vendor
if (truckCarriage.getLoad().hasCarriage()) {
	// since truck carriage load type was truck, 
	//the method of truck hasCarriage was accessible here
	//this is not possible if the function get/setLoad 
	// was written with "any" as argument type


	// do stuff if he found a carriable truck
	console.log('Truck has another truck on it')

}

if (!truckCarriage.getLoad().hasRefregiration()) {
	// do stuff if he found a carriable truck
	console.log('No refregiration for the truck inside')

}

Imagination
class TruckCarrier extends Truck<TruckCarrier>

FruitsCarrier extends Truck<Fruit>