description

# asFuture<E> method Null safety

Future<E> asFuture <E>(

1. [E? futureValue]

)

Returns a future that handles the onDone and onError callbacks.

This method overwrites the existing onDone and onError callbacks with new ones that complete the returned future.

In case of an error the subscription will automatically cancel (even when it was listening with `cancelOnError` set to `false`).

In case of a `done` event the future completes with the given `futureValue`.

If `futureValue` is omitted, the value `null as E` is used as a default. If `E` is not nullable, this will throw immediately when asFuture is called.

## Implementation

    Future<E> asFuture<E>([E? futureValue]);