Node.js

13.6    Type Aliases in TypeScript

In addition to interfaces, TypeScript also allows you to define type aliases by using the type keyword. Type aliases are used in a similar way as interfaces, but are somewhat simpler in structure. Listing 13.27 shows that you can implement the example with interfaces in a similar way with type aliases. The biggest difference is that a class can’t implement a type alias.

type Movie = {  id: number;  title: string;  year: number;  rating: number;  rate(rating: number): void;}; class ActionMovie {  public rating = 0;  constructor(public id: number, public title: string, public year: number) {}   rate(rating: number) {    this.rating = rating;  }} function show(movie: Movie) {  console.log('Now showing: ', movie.title);}