List Reduce TypeScript

by ozzymcduff

HTML

<div id="app"></div>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#app {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  transition: all 0.2s;
  text-align: center;
}

TypeScript

interface Person {
  firstName: string;
  lastName:  string;
}

function greeter(person: Person) {
  return "Hello, " + person.firstName + " " + person.lastName;
}

let user1 = {
	id: 1,
	firstName: "Malcolm",
  lastName:  "Reynolds"
};
let user2 = {
	id: 2,
	firstName: "Richard",
  lastName:  "Reynolds"
};
let user3 = {
	id: 3,
	firstName: "Evelyn",
  lastName:  "Reynolds"
};

function presenter(l:Array<Person>, p:Person){
	const found =	l.reduce((memo,item)=>{return memo || item.id===p.id;}, false);
	return found?"found":"not found";
}

document.querySelector("#app").innerHTML = greeter(user1)+" "+presenter([user1,user2,user3], user1);