/*
* This file is part of the DXX-Rebirth project .
* It is copyright by its individual contributors, as recorded in the
* project's Git history. See COPYING.txt at the top level for license
* terms and a link to the Git history.
*/
#pragma once
#include
#include
namespace detail {
/* In the general case, a range is ephemeral if `T` is an rvalue reference,
* since an rvalue may be moved or destroyed by the end of the statement.
*/
template
std::is_rvalue_reference is_ephemeral_range(...);
/* As a special exception to the general case, if the type T defines an inner
* type `range_owns_iterated_storage`, delegate the test to that type. This
* allows a type T to declare that it is only a view on longer-lived storage,
* and therefore the storage is not ephemeral even when `T` is an rvalue
* reference.
*/
template
typename std::remove_reference::type::range_owns_iterated_storage is_ephemeral_range(std::nullptr_t);
}
/* Define a convenience helper that applies the `is_ephemeral_range` test to
* any number of types.
*/
template
using any_ephemeral_range = std::disjunction(nullptr))...>;