| // Pair implementation -*- C++ -*- |
| |
| // Copyright (C) 2001-2016 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/>. |
| |
| /* |
| * |
| * Copyright (c) 1994 |
| * Hewlett-Packard Company |
| * |
| * Permission to use, copy, modify, distribute and sell this software |
| * and its documentation for any purpose is hereby granted without fee, |
| * provided that the above copyright notice appear in all copies and |
| * that both that copyright notice and this permission notice appear |
| * in supporting documentation. Hewlett-Packard Company makes no |
| * representations about the suitability of this software for any |
| * purpose. It is provided "as is" without express or implied warranty. |
| * |
| * |
| * Copyright (c) 1996,1997 |
| * Silicon Graphics Computer Systems, Inc. |
| * |
| * Permission to use, copy, modify, distribute and sell this software |
| * and its documentation for any purpose is hereby granted without fee, |
| * provided that the above copyright notice appear in all copies and |
| * that both that copyright notice and this permission notice appear |
| * in supporting documentation. Silicon Graphics makes no |
| * representations about the suitability of this software for any |
| * purpose. It is provided "as is" without express or implied warranty. |
| */ |
| |
| /** @file bits/stl_pair.h |
| * This is an internal header file, included by other library headers. |
| * Do not attempt to use it directly. @headername{utility} |
| */ |
| |
| #ifndef _STL_PAIR_H |
| #define _STL_PAIR_H 1 |
| |
| #include <bits/move.h> // for std::move / std::forward, and std::swap |
| |
| #if __cplusplus >= 201103L |
| #include <type_traits> // for std::__decay_and_strip too |
| #endif |
| |
| namespace std _GLIBCXX_VISIBILITY(default) |
| { |
| _GLIBCXX_BEGIN_NAMESPACE_VERSION |
| |
| /** |
| * @addtogroup utilities |
| * @{ |
| */ |
| |
| #if __cplusplus >= 201103L |
| /// piecewise_construct_t |
| struct piecewise_construct_t { explicit piecewise_construct_t() = default; }; |
| |
| /// piecewise_construct |
| constexpr piecewise_construct_t piecewise_construct = piecewise_construct_t(); |
| |
| // Forward declarations. |
| template<typename...> |
| class tuple; |
| |
| template<std::size_t...> |
| struct _Index_tuple; |
| |
| // Concept utility functions, reused in conditionally-explicit |
| // constructors. |
| // See PR 70437, don't look at is_constructible or |
| // is_convertible if the decayed types are the same to |
| // avoid querying those properties for incomplete types. |
| template <typename _T1, typename _T2, typename _U1, typename _U2> |
| constexpr bool _ConstructiblePair() |
| { |
| return __and_<__or_<is_same<typename decay<_T1>::type, |
| typename decay<_U1>::type>, |
| is_constructible<_T1, const _U1&>>, |
| __or_<is_same<typename decay<_T2>::type, |
| typename decay<_U2>::type>, |
| is_constructible<_T2, const _U2&>>>::value; |
| } |
| |
| template <typename _T1, typename _T2, typename _U1, typename _U2> |
| constexpr bool _ImplicitlyConvertiblePair() |
| { |
| return __and_<__or_<is_same<typename decay<_T1>::type, |
| typename decay<_U1>::type>, |
| is_convertible<const _U1&, _T1>>, |
| __or_<is_same<typename decay<_T2>::type, |
| typename decay<_U2>::type>, |
| is_convertible<const _U2&, _T2>>>::value; |
| } |
| |
| template <typename _T1, typename _T2, typename _U1, typename _U2> |
| constexpr bool _MoveConstructiblePair() |
| { |
| return __and_<__or_<is_same<typename decay<_T1>::type, |
| typename decay<_U1>::type>, |
| is_constructible<_T1, _U1&&>>, |
| __or_<is_same<typename decay<_T2>::type, |
| typename decay<_U2>::type>, |
| is_constructible<_T2, _U2&&>>>::value; |
| } |
| |
| template <typename _T1, typename _T2, typename _U1, typename _U2> |
| constexpr bool _ImplicitlyMoveConvertiblePair() |
| { |
| return __and_<__or_<is_same<typename decay<_T1>::type, |
| typename decay<_U1>::type>, |
| is_convertible<_U1&&, _T1>>, |
| __or_<is_same<typename decay<_T2>::type, |
| typename decay<_U2>::type>, |
| is_convertible<_U2&&, _T2>>>::value; |
| } |
| |
| |
| #endif |
| |
| /** |
| * @brief Struct holding two objects of arbitrary type. |
| * |
| * @tparam _T1 Type of first object. |
| * @tparam _T2 Type of second object. |
| */ |
| template<typename _T1, typename _T2> |
| struct pair |
| { |
| typedef _T1 first_type; /// @c first_type is the first bound type |
| typedef _T2 second_type; /// @c second_type is the second bound type |
| |
| _T1 first; /// @c first is a copy of the first object |
| _T2 second; /// @c second is a copy of the second object |
| |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // 265. std::pair::pair() effects overly restrictive |
| /** The default constructor creates @c first and @c second using their |
| * respective default constructors. */ |
| #if __cplusplus >= 201103L |
| template <typename _U1 = _T1, |
| typename _U2 = _T2, |
| typename enable_if<__and_< |
| __is_implicitly_default_constructible<_U1>, |
| __is_implicitly_default_constructible<_U2>> |
| ::value, bool>::type = true> |
| #endif |
| _GLIBCXX_CONSTEXPR pair() |
| : first(), second() { } |
| |
| #if __cplusplus >= 201103L |
| template <typename _U1 = _T1, |
| typename _U2 = _T2, |
| typename enable_if<__and_< |
| is_default_constructible<_U1>, |
| is_default_constructible<_U2>, |
| __not_< |
| __and_<__is_implicitly_default_constructible<_U1>, |
| __is_implicitly_default_constructible<_U2>>>> |
| ::value, bool>::type = false> |
| explicit constexpr pair() |
| : first(), second() { } |
| #endif |
| |
| /** Two objects may be passed to a @c pair constructor to be copied. */ |
| #if __cplusplus < 201103L |
| pair(const _T1& __a, const _T2& __b) |
| : first(__a), second(__b) { } |
| #else |
| template<typename _U1 = _T1, typename _U2=_T2, typename |
| enable_if<_ConstructiblePair<_T1, _T2, _U1, _U2>() |
| && _ImplicitlyConvertiblePair<_T1, _T2, _U1, _U2>(), |
| bool>::type=true> |
| constexpr pair(const _T1& __a, const _T2& __b) |
| : first(__a), second(__b) { } |
| |
| template<typename _U1 = _T1, typename _U2=_T2, typename |
| enable_if<_ConstructiblePair<_T1, _T2, _U1, _U2>() |
| && !_ImplicitlyConvertiblePair<_T1, _T2, _U1, _U2>(), |
| bool>::type=false> |
| explicit constexpr pair(const _T1& __a, const _T2& __b) |
| : first(__a), second(__b) { } |
| #endif |
| |
| /** There is also a templated copy ctor for the @c pair class itself. */ |
| #if __cplusplus < 201103L |
| template<typename _U1, typename _U2> |
| pair(const pair<_U1, _U2>& __p) |
| : first(__p.first), second(__p.second) { } |
| #else |
| template<typename _U1, typename _U2, typename |
| enable_if<_ConstructiblePair<_T1, _T2, _U1, _U2>() |
| && _ImplicitlyConvertiblePair<_T1, _T2, _U1, _U2>(), |
| bool>::type=true> |
| constexpr pair(const pair<_U1, _U2>& __p) |
| : first(__p.first), second(__p.second) { } |
| |
| template<typename _U1, typename _U2, typename |
| enable_if<_ConstructiblePair<_T1, _T2, _U1, _U2>() |
| && !_ImplicitlyConvertiblePair<_T1, _T2, _U1, _U2>(), |
| bool>::type=false> |
| explicit constexpr pair(const pair<_U1, _U2>& __p) |
| : first(__p.first), second(__p.second) { } |
| |
| constexpr pair(const pair&) = default; |
| constexpr pair(pair&&) = default; |
| |
| // DR 811. |
| template<typename _U1, typename |
| enable_if<_ConstructiblePair<_T2, _T2, _T2, _T2>() |
| && _MoveConstructiblePair<_T1, _T2, _U1, _T2>() |
| && _ImplicitlyConvertiblePair<_T2, _T2, _T2, _T2>() |
| && _ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _U1, _T2>(), |
| bool>::type=true> |
| constexpr pair(_U1&& __x, const _T2& __y) |
| : first(std::forward<_U1>(__x)), second(__y) { } |
| |
| template<typename _U1, typename |
| enable_if<_ConstructiblePair<_T2, _T2, _T2, _T2>() |
| && _MoveConstructiblePair<_T1, _T2, _U1, _T2>() |
| && (!_ImplicitlyConvertiblePair<_T2, _T2, _T2, _T2>() |
| || !_ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _U1, _T2>()), |
| bool>::type=false> |
| explicit constexpr pair(_U1&& __x, const _T2& __y) |
| : first(std::forward<_U1>(__x)), second(__y) { } |
| |
| template<typename _U2, typename |
| enable_if<_ConstructiblePair<_T1, _T1, _T1, _T1>() |
| && _MoveConstructiblePair<_T1, _T2, _T1, _U2>() |
| && _ImplicitlyConvertiblePair<_T1, _T1, _T1, _T1>() |
| && _ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _T1, _U2>(), |
| bool>::type=true> |
| constexpr pair(const _T1& __x, _U2&& __y) |
| : first(__x), second(std::forward<_U2>(__y)) { } |
| |
| template<typename _U2, typename |
| enable_if<_ConstructiblePair<_T1, _T1, _T1, _T1>() |
| && _MoveConstructiblePair<_T1, _T2, _T1, _U2>() |
| && (!_ImplicitlyConvertiblePair<_T1, _T1, _T1, _T1>() |
| || !_ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _T1, _U2>()), |
| bool>::type=false> |
| explicit pair(const _T1& __x, _U2&& __y) |
| : first(__x), second(std::forward<_U2>(__y)) { } |
| |
| template<typename _U1, typename _U2, typename |
| enable_if<_MoveConstructiblePair<_T1, _T2, _U1, _U2>() |
| && _ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _U1, _U2>(), |
| bool>::type=true> |
| constexpr pair(_U1&& __x, _U2&& __y) |
| : first(std::forward<_U1>(__x)), second(std::forward<_U2>(__y)) { } |
| |
| template<typename _U1, typename _U2, typename |
| enable_if<_MoveConstructiblePair<_T1, _T2, _U1, _U2>() |
| && !_ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _U1, _U2>(), |
| bool>::type=false> |
| explicit constexpr pair(_U1&& __x, _U2&& __y) |
| : first(std::forward<_U1>(__x)), second(std::forward<_U2>(__y)) { } |
| |
| |
| template<typename _U1, typename _U2, typename |
| enable_if<_MoveConstructiblePair<_T1, _T2, _U1, _U2>() |
| && _ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _U1, _U2>(), |
| bool>::type=true> |
| constexpr pair(pair<_U1, _U2>&& __p) |
| : first(std::forward<_U1>(__p.first)), |
| second(std::forward<_U2>(__p.second)) { } |
| |
| template<typename _U1, typename _U2, typename |
| enable_if<_MoveConstructiblePair<_T1, _T2, _U1, _U2>() |
| && !_ImplicitlyMoveConvertiblePair<_T1, _T2, |
| _U1, _U2>(), |
| bool>::type=false> |
| explicit constexpr pair(pair<_U1, _U2>&& __p) |
| : first(std::forward<_U1>(__p.first)), |
| second(std::forward<_U2>(__p.second)) { } |
| |
| template<typename... _Args1, typename... _Args2> |
| pair(piecewise_construct_t, tuple<_Args1...>, tuple<_Args2...>); |
| |
| pair& |
| operator=(const pair& __p) |
| { |
| first = __p.first; |
| second = __p.second; |
| return *this; |
| } |
| |
| pair& |
| operator=(pair&& __p) |
| noexcept(__and_<is_nothrow_move_assignable<_T1>, |
| is_nothrow_move_assignable<_T2>>::value) |
| { |
| first = std::forward<first_type>(__p.first); |
| second = std::forward<second_type>(__p.second); |
| return *this; |
| } |
| |
| template<typename _U1, typename _U2> |
| pair& |
| operator=(const pair<_U1, _U2>& __p) |
| { |
| first = __p.first; |
| second = __p.second; |
| return *this; |
| } |
| |
| template<typename _U1, typename _U2> |
| pair& |
| operator=(pair<_U1, _U2>&& __p) |
| { |
| first = std::forward<_U1>(__p.first); |
| second = std::forward<_U2>(__p.second); |
| return *this; |
| } |
| |
| void |
| swap(pair& __p) |
| noexcept(__is_nothrow_swappable<_T1>::value |
| && __is_nothrow_swappable<_T2>::value) |
| { |
| using std::swap; |
| swap(first, __p.first); |
| swap(second, __p.second); |
| } |
| |
| private: |
| template<typename... _Args1, std::size_t... _Indexes1, |
| typename... _Args2, std::size_t... _Indexes2> |
| pair(tuple<_Args1...>&, tuple<_Args2...>&, |
| _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>); |
| #endif |
| }; |
| |
| /// Two pairs of the same type are equal iff their members are equal. |
| template<typename _T1, typename _T2> |
| inline _GLIBCXX_CONSTEXPR bool |
| operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) |
| { return __x.first == __y.first && __x.second == __y.second; } |
| |
| /// <http://gcc.gnu.org/onlinedocs/libstdc++/manual/utilities.html> |
| template<typename _T1, typename _T2> |
| inline _GLIBCXX_CONSTEXPR bool |
| operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) |
| { return __x.first < __y.first |
| || (!(__y.first < __x.first) && __x.second < __y.second); } |
| |
| /// Uses @c operator== to find the result. |
| template<typename _T1, typename _T2> |
| inline _GLIBCXX_CONSTEXPR bool |
| operator!=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) |
| { return !(__x == __y); } |
| |
| /// Uses @c operator< to find the result. |
| template<typename _T1, typename _T2> |
| inline _GLIBCXX_CONSTEXPR bool |
| operator>(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) |
| { return __y < __x; } |
| |
| /// Uses @c operator< to find the result. |
| template<typename _T1, typename _T2> |
| inline _GLIBCXX_CONSTEXPR bool |
| operator<=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) |
| { return !(__y < __x); } |
| |
| /// Uses @c operator< to find the result. |
| template<typename _T1, typename _T2> |
| inline _GLIBCXX_CONSTEXPR bool |
| operator>=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y) |
| { return !(__x < __y); } |
| |
| #if __cplusplus >= 201103L |
| /// See std::pair::swap(). |
| // Note: no std::swap overloads in C++03 mode, this has performance |
| // implications, see, eg, libstdc++/38466. |
| template<typename _T1, typename _T2> |
| inline void |
| swap(pair<_T1, _T2>& __x, pair<_T1, _T2>& __y) |
| noexcept(noexcept(__x.swap(__y))) |
| { __x.swap(__y); } |
| #endif |
| |
| /** |
| * @brief A convenience wrapper for creating a pair from two objects. |
| * @param __x The first object. |
| * @param __y The second object. |
| * @return A newly-constructed pair<> object of the appropriate type. |
| * |
| * The standard requires that the objects be passed by reference-to-const, |
| * but LWG issue #181 says they should be passed by const value. We follow |
| * the LWG by default. |
| */ |
| // _GLIBCXX_RESOLVE_LIB_DEFECTS |
| // 181. make_pair() unintended behavior |
| #if __cplusplus >= 201103L |
| // NB: DR 706. |
| template<typename _T1, typename _T2> |
| constexpr pair<typename __decay_and_strip<_T1>::__type, |
| typename __decay_and_strip<_T2>::__type> |
| make_pair(_T1&& __x, _T2&& __y) |
| { |
| typedef typename __decay_and_strip<_T1>::__type __ds_type1; |
| typedef typename __decay_and_strip<_T2>::__type __ds_type2; |
| typedef pair<__ds_type1, __ds_type2> __pair_type; |
| return __pair_type(std::forward<_T1>(__x), std::forward<_T2>(__y)); |
| } |
| #else |
| template<typename _T1, typename _T2> |
| inline pair<_T1, _T2> |
| make_pair(_T1 __x, _T2 __y) |
| { return pair<_T1, _T2>(__x, __y); } |
| #endif |
| |
| /// @} |
| |
| _GLIBCXX_END_NAMESPACE_VERSION |
| } // namespace std |
| |
| #endif /* _STL_PAIR_H */ |
