namespace Mankind {

export interface Human {

sayHello(): string;

getSecretNickname(): string;

}

export class Person implements Human {

public firstName: string;

public lastName: string;

private nickname: string;

constructor(firstName: string, lastName: string, nickname: string) {

this.firstName = firstName;

this.lastName = lastName;

this.nickname = nickname;

}

public sayHello(): string {

return `Hello, ${this.firstName} ${this.lastName}!`

}

public getSecretNickname(): string {

return this.nickname;

}

}

}

import Person = Mankind.Person;

let me = new Person("Baptiste", "Vannesson", "Bada");

console.log(me.firstName, me.lastName); // OK

console.log(me.sayHello()); // OK

// console.log(me.nickname); Oops! Undefined!

console.log(me.getSecretNickname()); // OK