(How) can I make a constant that is either zero or null depending
on how it is used?
Vulkan has a VK_NULL_HANDLE constant which in C is defined to be
zero. It is used as a null object for several types of objects.
In D however, zero is not implicitly convertible to a null
pointer, and vice versa.
On 64 bit platforms, those types are all pointers, so there I can
define VK_NULL_HANDLE as null. But on 32 bit platforms, some of
the types are pointers and others are ulongs, and my definition
of VK_NULL_HANDLE should be compatible with both.
Anyone have an idea on how to make this work?
