Modern Front-End Development for Rails, 2nd Edition

Using Enums and Literal Types

TypeScript is nothing if not chock full of many different ways to specify a type that is limited to a few values. We’ve just looked at literal types, but those are effectively just a subset of what you can do in TypeScript using an enumerated type, or enum.

Defining Enums

TypeScript enums are very flexible and allow you to do a lot of things that seem, frankly, to be rather pointless. I’ll try to minimize talking about the pointless parts.

At the simplest, you can define an enum in TypeScript just by providing a list of values for it. So if we wanted to convert our TicketStatus type to an enum, we could do this:

chapter_13/02/app/javascript/contexts/venue_types.ts

export enum TicketStatus {
  Unsold,
 Held, ...