Deferred
A purely functional synchronization primitive which represents a single value
which may not yet be available.
which may not yet be available.
When created, a
and never be made empty again.
Deferred is empty. It can then be completed exactly once,and never be made empty again.
get on an empty Deferred will block until the Deferred is completed.get on a completed Deferred will always immediately return its content.complete(a) on an empty Deferred will set it to a, and notify any andall readers currently blocked on a call to
get.complete(a) on a Deferred that has already been completed will not modifyits content, and result in a failed
F.Albeit simple,
complex concurrent behaviour and data structures like queues and semaphores.
Deferred can be used in conjunction with Ref to buildcomplex concurrent behaviour and data structures like queues and semaphores.
Finally, the blocking mentioned above is semantic only, no actual threads are
blocked by the implementation.
blocked by the implementation.
- Companion
- object
Value members
Methods
Obtains the value of the
The returned value may be canceled.
Deferred, or waits until it has been completed.The returned value may be canceled.