Utilize the type constant to retrieve a specific value in typescript

Is it possible to retrieve the constant value from the type with this specific definition?

type Dummy = {
  type: "dummy"
}

For instance, something along the lines of

Extract<Dummy["type"]>

Answer №1

At compile time, types are removed from your source code, meaning there is no way to extract values from them.

However, you can still obtain a type from a constant.

const example = { type: "Example" } as const
// Using `as const` results in `{ type: "Example" }` instead of `{ type: string }`
type ExampleType = typeof example

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