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Hasty Treat - Enums in JS (GraphQL and Typescript)

In this Hasty Treat, Scott and Wes talk about enums in JS — what they are, what they do, and how they work in JavaScript.

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Show Notes

03:11 - What are enums?

  • A type restricting variables to one value from a predefined set of constants
  • Direction = UP / DOWN / LEFT / RIGHT
  • Role = ADMIN EDITOR AUTHOR VIEWER
  • Day of the Week

05:12 - In GraphQL

  • enum Role { ADMIN EDITOR AUTHOR VIEWER}
  • Then

07:05 - In TypeScript

  • First, declare the type:
    • enum direction = { UP, DOWN, LEFT, RIGHT }
  • Then when you defined your function, use that type
    • type User { role: Role } or type User { role: [Role] }

08:49 - In JavaScript

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