// We're registering a service type after 'locking down' the container here and that means that the
// type is added to a copy of the registrations dictionary and the original replaced with a new one.
// This 'reference swapping' is thread-safe, but can result in types disappearing again from the
// registrations when multiple threads simultaneously add different types. This however, does not
// result in a consistency problem, because the missing type will be again added later. This type of
// swapping safes us from using locks.
private void AppendRootInstanceProducer(Type serviceType, InstanceProducer?rootProducer)
{
Helpers.InterlockedAddAndReplace(ref this.rootProducerCache, serviceType, rootProducer);
if (rootProducer != null)
{
this.RemoveExternalProducer(rootProducer);
}
}
