What is the name of this `unSequence` function?

sequence.ts

export function sequence<T>(
  map: Map<string, Promise<T>>
): Promise<Map<string, T>> {
  return Promise.all(
    Array.from(map, ([key, promisedValue]) =>
      promisedValue.then<[string, T]>(value => [key, value])
    )
  ).then((entries) => new Map(entries));
}

export function unSequence<T>(
  promisedMap: Promise<Map<string, T>>,
  keys: string[]
): Map<string, Promise<T | undefined>> {
  return new Map(
    keys.map(key =>
      [key, promisedMap.then(map => map.get(key))]
    )
  );
}