enable_special_members.h
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// <bits/enable_special_members.h> -*- C++ -*-
// Copyright (C) 2013-2021 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/enable_special_members.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly.
*/
#ifndef _ENABLE_SPECIAL_MEMBERS_H
#define _ENABLE_SPECIAL_MEMBERS_H 1
#pragma GCC system_header
#include <bits/c++config.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/// @cond undocumented
struct _Enable_default_constructor_tag
{
explicit constexpr _Enable_default_constructor_tag() = default;
};
/**
* @brief A mixin helper to conditionally enable or disable the default
* constructor.
* @sa _Enable_special_members
*/
template<bool _Switch, typename _Tag = void>
struct _Enable_default_constructor
{
constexpr _Enable_default_constructor() noexcept = default;
constexpr _Enable_default_constructor(_Enable_default_constructor const&)
noexcept = default;
constexpr _Enable_default_constructor(_Enable_default_constructor&&)
noexcept = default;
_Enable_default_constructor&
operator=(_Enable_default_constructor const&) noexcept = default;
_Enable_default_constructor&
operator=(_Enable_default_constructor&&) noexcept = default;
// Can be used in other ctors.
constexpr explicit
_Enable_default_constructor(_Enable_default_constructor_tag) { }
};
/**
* @brief A mixin helper to conditionally enable or disable the default
* destructor.
* @sa _Enable_special_members
*/
template<bool _Switch, typename _Tag = void>
struct _Enable_destructor { };
/**
* @brief A mixin helper to conditionally enable or disable the copy/move
* special members.
* @sa _Enable_special_members
*/
template<bool _Copy, bool _CopyAssignment,
bool _Move, bool _MoveAssignment,
typename _Tag = void>
struct _Enable_copy_move { };
/**
* @brief A mixin helper to conditionally enable or disable the special
* members.
*
* The @c _Tag type parameter is to make mixin bases unique and thus avoid
* ambiguities.
*/
template<bool _Default, bool _Destructor,
bool _Copy, bool _CopyAssignment,
bool _Move, bool _MoveAssignment,
typename _Tag = void>
struct _Enable_special_members
: private _Enable_default_constructor<_Default, _Tag>,
private _Enable_destructor<_Destructor, _Tag>,
private _Enable_copy_move<_Copy, _CopyAssignment,
_Move, _MoveAssignment,
_Tag>
{ };
// Boilerplate follows.
template<typename _Tag>
struct _Enable_default_constructor<false, _Tag>
{
constexpr _Enable_default_constructor() noexcept = delete;
constexpr _Enable_default_constructor(_Enable_default_constructor const&)
noexcept = default;
constexpr _Enable_default_constructor(_Enable_default_constructor&&)
noexcept = default;
_Enable_default_constructor&
operator=(_Enable_default_constructor const&) noexcept = default;
_Enable_default_constructor&
operator=(_Enable_default_constructor&&) noexcept = default;
// Can be used in other ctors.
constexpr explicit
_Enable_default_constructor(_Enable_default_constructor_tag) { }
};
template<typename _Tag>
struct _Enable_destructor<false, _Tag>
{ ~_Enable_destructor() noexcept = delete; };
template<typename _Tag>
struct _Enable_copy_move<false, true, true, true, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = default;
};
template<typename _Tag>
struct _Enable_copy_move<true, false, true, true, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = default;
};
template<typename _Tag>
struct _Enable_copy_move<false, false, true, true, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = default;
};
template<typename _Tag>
struct _Enable_copy_move<true, true, false, true, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = default;
};
template<typename _Tag>
struct _Enable_copy_move<false, true, false, true, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = default;
};
template<typename _Tag>
struct _Enable_copy_move<true, false, false, true, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = default;
};
template<typename _Tag>
struct _Enable_copy_move<false, false, false, true, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = default;
};
template<typename _Tag>
struct _Enable_copy_move<true, true, true, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
template<typename _Tag>
struct _Enable_copy_move<false, true, true, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
template<typename _Tag>
struct _Enable_copy_move<true, false, true, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
template<typename _Tag>
struct _Enable_copy_move<false, false, true, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
template<typename _Tag>
struct _Enable_copy_move<true, true, false, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
template<typename _Tag>
struct _Enable_copy_move<false, true, false, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = default;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
template<typename _Tag>
struct _Enable_copy_move<true, false, false, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
template<typename _Tag>
struct _Enable_copy_move<false, false, false, false, _Tag>
{
constexpr _Enable_copy_move() noexcept = default;
constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move const&) noexcept = delete;
_Enable_copy_move&
operator=(_Enable_copy_move&&) noexcept = delete;
};
/// @endcond
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // _ENABLE_SPECIAL_MEMBERS_H
c++config.h
std
ISO C++ entities toplevel namespace is std.