How to call async methods from within a Prism event aggregator subscriber?

Question

Quick question - how do I call async methods from within a Prism event aggregator subscriber action? E.g.

_eventAggregator.GetEvent<PubSubEvent<SomeMessage>>()
   .Subscribe((msg) => {
                       DoSomething();
                       await DoSomethingAsync();
                       DoSomethingElse();
                    });

Answer 1

Just making @Charles Mager a answer

_eventAggregator.GetEvent<PubSubEvent<SomeMessage>>()
   .Subscribe(async(msg) => {
                       DoSomething();
                       await DoSomethingAsync();
                       DoSomethingElse();
                    });

Answer 2

With current Prism implementation, it is not possible see here.

But I have found an alternate implementation of Prism's EventAggregator, which allows async subscriptions. See here.

This new event async aggregator overloads can be used in the same way as the original one:

Subscription to event is exactly the same with another overload:

    _eventAggregator.GetEvent<<TfsHookEvent<WorkItemUpdatedPayload>>().Subscribe(WorkItem_Updated);

Event handler:

    private async Task WorkItem_Updated(WorkItemUpdatedPayload obj)
    {
        await CheckAsync();
    }