This is information that the compiler already has, and should be exposed
so that the library doesn't need to reimplement the exact same
functionality.
- __is_nullptr
- __is_bounded_array
- __is_scoped_enum
- __is_unbounded_array
- __is_copy_constructible
- __is_move_constructible
- __is_copy_assignable
- __is_move_assignable
- __is_referenceable
Is a VLA a bounded array? (We support those as an extension in C++, unfortunately.)