shortcut for TS `undefined as Type | undefined`

Question

I have a const like this:

const DEFAULT = {
  result: undefined as Result | undefined,
};

The type of result seems too long for me. Is there a way to shorten it?

Answer 1

You could explicitly declare the type and use the shorthand optional property notation in the type signature. After that, you don't need to explicitly declare the property undefined in the object as that is the default.

type Result = true;

const DEFAULT: { result?: Result } = {};

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