Sample subs and unsubs code

sample.ts

const score = new Score();

const display = new DisplayScore();
const cli = new CliScore();

score.subscribe(display);
score.subscribe(cli);

score.updateScore(4);

score.unsubscribe(cli);

score.updateScore(5);

score.unsubscribe(display);

score.updateScore(6);

//The above will output
/*
got new score.....
Display score: 4
CLI score: 4
observer detached...CliScore
got new score.....
Display score: 5
observer detached...DisplayScore
got new score.....
*/