Function lastX

src/utils/generators.ts:3–12

(as: AsyncGenerator<A>)

const NO_VALUE = Symbol('NO_VALUE')

export async function lastX<A>(as: AsyncGenerator<A>): Promise<A> {
  let lastValue: A | typeof NO_VALUE = NO_VALUE
  for await (const a of as) {
    lastValue = a
  }
  if (lastValue === NO_VALUE) {
    throw new Error('No items in generator')
  }
  return lastValue
}

export async function returnValue<A>(
  as: AsyncGenerator<unknown, A>,