Strategy Design Patter in TS

ts-design-patterns-strategy.ts

// Strategy design pattern
interface QuackBehavior {
    quack(): void;
}

class Quack implements QuackBehavior {
    quack() {
        console.log('quack');
    }
}

class Squeack implements QuackBehavior {
    quack() {
        console.log('squeack');
    }
}

class Duck {
    quackBehavior: QuackBehavior;

    constructor(initQuackBehavior: QuackBehavior) {
        this.quackBehavior = initQuackBehavior;
    }

    quack() {
        this.quackBehavior.quack();
    }
}

const d1 = new Duck(new Quack());
const d2 = new Duck(new Squeack());
d1.quack();
d2.quack();

d1.quackBehavior = new Squeack();
d1.quack();