Bent Rasmussen wrote: > Not true. It wraps the value type in a struct with a boolean field > expressing whether it is null or not. > > http://msdn.microsoft.com/en-us/library/1t3y8s4s(VS.80).aspx Indeed. Thanks for pointing that out. So C#'s 'foo?' syntax has even less to do with this compile-time nullness checking. L.