static void RegisterCancelation<T>(AsyncSubject<T> subject, IDisposable subscription, CancellationToken token)
{
//
// Separate method used to avoid heap allocation of closure when no cancellation is needed,
// e.g. when CancellationToken.None is provided to the RunAsync overloads.
//
var ctr = token.Register(() =>
{
subscription.Dispose();
Cancel(subject, token);
});
//
// No null-check for ctr is needed:
//
// - CancellationTokenRegistration is a struct
// - Registration will succeed 99% of the time, no warranting an attempt to avoid spurious Subscribe calls
//
subject.Subscribe(Stubs<T>.Ignore, _ => ctr.Dispose(), ctr.Dispose);
}
