const names: string[] = ['Foo', 'Bar'];
names[2];

type Names = [ string, string ];
const names: Names = ['Foo', 'Bar'];
names[2];

type Names<TItem, TLength extends number> = [TItem, ...TItem[]] & { length: TLength };
const names: Names<string, 2> = ['Foo', 'Bar'];
names[2];

interface Person {
  name: string;
  age: number;
};
const person: Person = {
  name: 'Jarid',
  age: 35
};
person.foo;

declare function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K>;
interface Person {
  name: string;
  age: number;
};
const person: Person = {
  name: 'Jarid',
  age: 35
};
const subperson = pick(person, 'name');
subperson.age;

declare function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K>;
interface Person {
  name: string;
  age: number;
};
const person: Person = {
  name: 'Jarid',
  age: 35
};
type KeyOfPerson = keyof Person;
const keysOfPerson: KeyOfPerson[] = ['name'];
const subperson = pick(person, ...keysOfPerson);
subperson.age;

declare function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K>;
interface Person {
  name: string;
  age: number;
};
const person: Person = {
  name: 'Jarid',
  age: 35
};
type KeysOfPerson = [ keyof Person ];
const keysOfPerson: KeysOfPerson = [ 'name' ];
const subperson = pick(person, ...keysOfPerson);
subperson.age;