Some value if promise is complete, otherwise None
Project promised value into an either containing the value or any exception thrown retrieving it.
Project promised value into an either containing the value or any
exception thrown retrieving it. Unwraps cause of any top-level
ExecutionException
Project any resulting exception or result into a unified type X
Create a left projection of a contained either
Project promised value into an Option containing the value if retrived with no exception
Create a right projection of a contained either
Facilitates projection over promised iterables