Blocks until the fork completes with a result. If the fork failed with an exception, this exception is not thrown, but returned as a Left.
Left
If the join is interrupted.
Blocks until the fork completes with a result.
If the fork completed with an exception, and is unsupervised (started with forkUnsupervised or forkCancellable.
If T is an Either, and there's an enclosing either block, the result can be unwrapped using either.ok.
T
Either