Named requirements: ProFacade
A type F meets the ProFacade requirements of a type P if F meets the ProBasicFacade requirements, and the following expressions are well-formed and have the specified semantics.
| Expressions | Semantics |
|---|---|
typename F::convention_types |
A tuple-like type that contains any number of distinct types Cs. Each type C in Cs shall meet the ProConvention requirements of P. |
typename F::reflection_types |
A tuple-like type that contains any number of distinct types Rs. Each type R in Rs shall meet the ProReflection requirements of P. |
F::max_size |
A core constant expression of type std::size_t that shall be greater than or equal to sizeof(P). |
F::max_align |
A core constant expression of type std::size_t that shall be greater than or equal to alignof(P). |
F::copyability |
A core constant expression of type constraint_level that defines the required copyability of P. |
F::relocatability |
A core constant expression of type constraint_level that defines the required relocatability of P. |
F::destructibility |
A core constant expression of type constraint_level that defines the required destructibility of P. |
Since 4.0.2: P shall be a pointer-like type eligible for proxy. A type P is eligible if P is not a specialization of proxy and the following condition is satisfied:
(requires { *std::declval<P&>(); } || requires { typename P::element_type; }) &&
requires { typename std::pointer_traits<P>::element_type; }
In other words, P either supports dereferencing or provides an element_type, and std::pointer_traits<P> yields a valid element_type.
Notes
Relocatability is defined as move-construct an object and then destroy the original instance. Specifically, the value of F::relocatability maps to the following requirements on P:
| Value | Requirement on P |
|---|---|
constraint_level::none |
None |
constraint_level::nontrivial |
(std::is_move_constructible_v<P> && std::is_destructible_v<P>) ||is_bitwise_trivially_relocatable_v<P> |
constraint_level::nothrow |
(std::is_nothrow_move_constructible_v<P> && std::is_nothrow_destructible_v<P>) ||is_bitwise_trivially_relocatable_v<P> |
constraint_level::trivial |
is_bitwise_trivially_relocatable_v<P> |