CODE EXAMPLE FOR TYPESCRIPT

ts Strategy pattern

// The Strategy pattern is a design pattern lets you define a family of algorithms, 
// encapsulate each one, and make them interchangeable.

// Implementing the Strategy pattern in Typescript is very easy and you can 
// start with this Strategy class

class Strategy {
  public LastElement(data: []) {
    return data[data.length - 1];
  }
}

const strategy = new Strategy();
const data = [1, 2, 3, 4, 5];

let last = strategy.LastElement(data);