As I mentioned in my comment, I think the reason why this doesn't work is because the compiler can't infer types based on generic constraints.
Below is an alternative implementation that will compile. I've revised the IAccess interface to only have the T generic type parameter.
interface ISignatur<T>
{
Type Type { get; }
}
interface IAccess<T>
{
ISignatur<T> Signature { get; }
T Value { get; set; }
}
class Signatur : ISignatur<bool>
{
public Type Type
{
get { return typeof(bool); }
}
}
class ServiceGate
{
public IAccess<T> Get<T>(ISignatur<T> sig)
{
throw new NotImplementedException();
}
}
static class Test
{
static void Main()
{
ServiceGate service = new ServiceGate();
var access = service.Get(new Signatur());
}
}