Learning Concurrency in Kotlin

Deferred

Deferred extends job in order to make it an asynchronous task that also has a result. Deferred is Kotlin's implementation of what other languages call Futures or Promises. The idea behind it is that a computation will return you an object that will be empty until the asynchronous task completes.

The life cycle of deferred and its states are similar to those of job, so the real differences are in return type—like we saw in the previous chapter—and error handling, as we will cover when we move ahead.

At the time of writing, deferred has a failed state, which doesn't exists in job. It is planned to remove it to simplify the life cycle of deferred. Because of this, it's advised that you don't base your usage of deferred around the