public static ReferenceCountedDisposable <T> Create <TDerived>(TDerived instance,
out ReferenceCountedDisposable <TDerived> .WeakReference derivedWeakReference)
where TDerived : class, IDisposable, T
{
var baseStrongRef = new ReferenceCountedDisposable <T>(instance);
derivedWeakReference =
new ReferenceCountedDisposable <TDerived> .WeakReference(instance, baseStrongRef._boxedReferenceCount);
return(baseStrongRef);
}
public WeakReference(ReferenceCountedDisposable <T> reference)
: this()
{
if (reference == null)
{
throw new ArgumentNullException(nameof(reference));
}
T?instance = reference._instance;
StrongBox <int> referenceCount = reference._boxedReferenceCount;
if (instance == null)
{
// The specified reference is already not valid. This case is supported by WeakReference (not
// unlike `new System.WeakReference(null)`), but we return early to avoid an unnecessary
// allocation in this case.
return;
}
_weakInstance = new WeakReference <T>(instance);
_boxedReferenceCount = referenceCount;
}