Define the type of error in function argument

Question

How do I define the type of error below?

async function falseThrow (promise: Promise<any>, error): any {
  let value: any = await promise
  if (!value) throw error
  return value
}

Answer 1

Exactly as you defined the type of promise being Promise<any> . You use : .

That depends on the type you want. If error is expected to be a string, then it would be:

async function falseThrow (promise: Promise<any>, error:string): any {
  let value: any = await promise
  if (!value) throw error
  return value
}

EDIT

Or you could use Error , if that's the case, as you stated on your own answer.

Answer 2

This works! Whoops, thought it did not.

async function falseThrow (promise: Promise<any>, error: Error): any {
  let value: any = await promise
  if (!value) throw error
  return value
}