// <utility> -*- C++ -*- // Copyright (C) 2001-2020 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 include/utility * This is a Standard C++ Library header. */ #ifndef _GLIBCXX_UTILITY #define _GLIBCXX_UTILITY 1 #pragma GCC system_header /** * @defgroup utilities Utilities * * Components deemed generally useful. Includes pair, tuple, * forward/move helpers, ratio, function object, metaprogramming and * type traits, time, date, and memory functions. */ #include <bits/c++config.h> #include <bits/stl_relops.h> #include <bits/stl_pair.h> #if __cplusplus >= 201103L #include <type_traits> #include <bits/move.h> #include <initializer_list> #if __cplusplus > 201703L #include <ext/numeric_traits.h> #endif namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION /// Finds the size of a given tuple type. template<typename _Tp> struct tuple_size; // _GLIBCXX_RESOLVE_LIB_DEFECTS // 2313. tuple_size should always derive from integral_constant<size_t, N> // 2770. tuple_size<const T> specialization is not SFINAE compatible template<typename _Tp, typename _Up = typename remove_cv<_Tp>::type, typename = typename enable_if<is_same<_Tp, _Up>::value>::type, size_t = tuple_size<_Tp>::value> using __enable_if_has_tuple_size = _Tp; template<typename _Tp> struct tuple_size<const __enable_if_has_tuple_size<_Tp>> : public tuple_size<_Tp> { }; template<typename _Tp> struct tuple_size<volatile __enable_if_has_tuple_size<_Tp>> : public tuple_size<_Tp> { }; template<typename _Tp> struct tuple_size<const volatile __enable_if_has_tuple_size<_Tp>> : public tuple_size<_Tp> { }; /// Gives the type of the ith element of a given tuple type. template<std::size_t __i, typename _Tp> struct tuple_element; // Duplicate of C++14's tuple_element_t for internal use in C++11 mode template<std::size_t __i, typename _Tp> using __tuple_element_t = typename tuple_element<__i, _Tp>::type; template<std::size_t __i, typename _Tp> struct tuple_element<__i, const _Tp> { typedef typename add_const<__tuple_element_t<__i, _Tp>>::type type; }; template<std::size_t __i, typename _Tp> struct tuple_element<__i, volatile _Tp> { typedef typename add_volatile<__tuple_element_t<__i, _Tp>>::type type; }; template<std::size_t __i, typename _Tp> struct tuple_element<__i, const volatile _Tp> { typedef typename add_cv<__tuple_element_t<__i, _Tp>>::type type; }; #if __cplusplus >= 201402L // The standard says this macro and alias template should be in <tuple> // but we define them here, to be available when the partial specializations // of tuple_element<pair<T,U>> and tuple_element<array<T,N>> are defined. #define __cpp_lib_tuple_element_t 201402L template<std::size_t __i, typename _Tp> using tuple_element_t = typename tuple_element<__i, _Tp>::type; #endif // Various functions which give std::pair a tuple-like interface. /// Partial specialization for std::pair template<typename _T1, typename _T2> struct __is_tuple_like_impl<std::pair<_T1, _T2>> : true_type { }; /// Partial specialization for std::pair template<class _Tp1, class _Tp2> struct tuple_size<std::pair<_Tp1, _Tp2>> : public integral_constant<std::size_t, 2> { }; /// Partial specialization for std::pair template<class _Tp1, class _Tp2> struct tuple_element<0, std::pair<_Tp1, _Tp2>> { typedef _Tp1 type; }; /// Partial specialization for std::pair template<class _Tp1, class _Tp2> struct tuple_element<1, std::pair<_Tp1, _Tp2>> { typedef _Tp2 type; }; template<std::size_t _Int> struct __pair_get; template<> struct __pair_get<0> { template<typename _Tp1, typename _Tp2> static constexpr _Tp1& __get(std::pair<_Tp1, _Tp2>& __pair) noexcept { return __pair.first; } template<typename _Tp1, typename _Tp2> static constexpr _Tp1&& __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept { return std::forward<_Tp1>(__pair.first); } template<typename _Tp1, typename _Tp2> static constexpr const _Tp1& __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept { return __pair.first; } template<typename _Tp1, typename _Tp2> static constexpr const _Tp1&& __const_move_get(const std::pair<_Tp1, _Tp2>&& __pair) noexcept { return std::forward<const _Tp1>(__pair.first); } }; template<> struct __pair_get<1> { template<typename _Tp1, typename _Tp2> static constexpr _Tp2& __get(std::pair<_Tp1, _Tp2>& __pair) noexcept { return __pair.second; } template<typename _Tp1, typename _Tp2> static constexpr _Tp2&& __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept { return std::forward<_Tp2>(__pair.second); } template<typename _Tp1, typename _Tp2> static constexpr const _Tp2& __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept { return __pair.second; } template<typename _Tp1, typename _Tp2> static constexpr const _Tp2&& __const_move_get(const std::pair<_Tp1, _Tp2>&& __pair) noexcept { return std::forward<const _Tp2>(__pair.second); } }; template<std::size_t _Int, class _Tp1, class _Tp2> constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type& get(std::pair<_Tp1, _Tp2>& __in) noexcept { return __pair_get<_Int>::__get(__in); } template<std::size_t _Int, class _Tp1, class _Tp2> constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&& get(std::pair<_Tp1, _Tp2>&& __in) noexcept { return __pair_get<_Int>::__move_get(std::move(__in)); } template<std::size_t _Int, class _Tp1, class _Tp2> constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type& get(const std::pair<_Tp1, _Tp2>& __in) noexcept { return __pair_get<_Int>::__const_get(__in); } template<std::size_t _Int, class _Tp1, class _Tp2> constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&& get(const std::pair<_Tp1, _Tp2>&& __in) noexcept { return __pair_get<_Int>::__const_move_get(std::move(__in)); } #if __cplusplus >= 201402L #define __cpp_lib_tuples_by_type 201304 template <typename _Tp, typename _Up> constexpr _Tp& get(pair<_Tp, _Up>& __p) noexcept { return __p.first; } template <typename _Tp, typename _Up> constexpr const _Tp& get(const pair<_Tp, _Up>& __p) noexcept { return __p.first; } template <typename _Tp, typename _Up> constexpr _Tp&& get(pair<_Tp, _Up>&& __p) noexcept { return std::move(__p.first); } template <typename _Tp, typename _Up> constexpr const _Tp&& get(const pair<_Tp, _Up>&& __p) noexcept { return std::move(__p.first); } template <typename _Tp, typename _Up> constexpr _Tp& get(pair<_Up, _Tp>& __p) noexcept { return __p.second; } template <typename _Tp, typename _Up> constexpr const _Tp& get(const pair<_Up, _Tp>& __p) noexcept { return __p.second; } template <typename _Tp, typename _Up> constexpr _Tp&& get(pair<_Up, _Tp>&& __p) noexcept { return std::move(__p.second); } template <typename _Tp, typename _Up> constexpr const _Tp&& get(const pair<_Up, _Tp>&& __p) noexcept { return std::move(__p.second); } #define __cpp_lib_exchange_function 201304 /// Assign @p __new_val to @p __obj and return its previous value. template <typename _Tp, typename _Up = _Tp> _GLIBCXX20_CONSTEXPR inline _Tp exchange(_Tp& __obj, _Up&& __new_val) { return std::__exchange(__obj, std::forward<_Up>(__new_val)); } #endif // C++14 // Stores a tuple of indices. Used by tuple and pair, and by bind() to // extract the elements in a tuple. template<size_t... _Indexes> struct _Index_tuple { }; #ifdef __has_builtin # if __has_builtin(__make_integer_seq) # define _GLIBCXX_USE_MAKE_INTEGER_SEQ 1 # endif #endif // Builds an _Index_tuple<0, 1, 2, ..., _Num-1>. template<size_t _Num> struct _Build_index_tuple { #if _GLIBCXX_USE_MAKE_INTEGER_SEQ template<typename, size_t... _Indices> using _IdxTuple = _Index_tuple<_Indices...>; using __type = __make_integer_seq<_IdxTuple, size_t, _Num>; #else using __type = _Index_tuple<__integer_pack(_Num)...>; #endif }; #if __cplusplus > 201103L #define __cpp_lib_integer_sequence 201304 /// Class template integer_sequence template<typename _Tp, _Tp... _Idx> struct integer_sequence { typedef _Tp value_type; static constexpr size_t size() noexcept { return sizeof...(_Idx); } }; /// Alias template make_integer_sequence template<typename _Tp, _Tp _Num> using make_integer_sequence #if _GLIBCXX_USE_MAKE_INTEGER_SEQ = __make_integer_seq<integer_sequence, _Tp, _Num>; #else = integer_sequence<_Tp, __integer_pack(_Num)...>; #endif #undef _GLIBCXX_USE_MAKE_INTEGER_SEQ /// Alias template index_sequence template<size_t... _Idx> using index_sequence = integer_sequence<size_t, _Idx...>; /// Alias template make_index_sequence template<size_t _Num> using make_index_sequence = make_integer_sequence<size_t, _Num>; /// Alias template index_sequence_for template<typename... _Types> using index_sequence_for = make_index_sequence<sizeof...(_Types)>; #endif #if __cplusplus > 201402L struct in_place_t { explicit in_place_t() = default; }; inline constexpr in_place_t in_place{}; template<typename _Tp> struct in_place_type_t { explicit in_place_type_t() = default; }; template<typename _Tp> inline constexpr in_place_type_t<_Tp> in_place_type{}; template<size_t _Idx> struct in_place_index_t { explicit in_place_index_t() = default; }; template<size_t _Idx> inline constexpr in_place_index_t<_Idx> in_place_index{}; template<typename> struct __is_in_place_type_impl : false_type { }; template<typename _Tp> struct __is_in_place_type_impl<in_place_type_t<_Tp>> : true_type { }; template<typename _Tp> struct __is_in_place_type : public __is_in_place_type_impl<_Tp> { }; #define __cpp_lib_as_const 201510 template<typename _Tp> constexpr add_const_t<_Tp>& as_const(_Tp& __t) noexcept { return __t; } template<typename _Tp> void as_const(const _Tp&&) = delete; #if __cplusplus > 201703L #define __cpp_lib_integer_comparison_functions 202002L template<typename _Tp, typename _Up> constexpr bool cmp_equal(_Tp __t, _Up __u) noexcept { static_assert(__is_standard_integer<_Tp>::value); static_assert(__is_standard_integer<_Up>::value); if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>) return __t == __u; else if constexpr (is_signed_v<_Tp>) return __t >= 0 && make_unsigned_t<_Tp>(__t) == __u; else return __u >= 0 && __t == make_unsigned_t<_Up>(__u); } template<typename _Tp, typename _Up> constexpr bool cmp_not_equal(_Tp __t, _Up __u) noexcept { return !std::cmp_equal(__t, __u); } template<typename _Tp, typename _Up> constexpr bool cmp_less(_Tp __t, _Up __u) noexcept { static_assert(__is_standard_integer<_Tp>::value); static_assert(__is_standard_integer<_Up>::value); if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>) return __t < __u; else if constexpr (is_signed_v<_Tp>) return __t < 0 || make_unsigned_t<_Tp>(__t) < __u; else return __u >= 0 && __t < make_unsigned_t<_Up>(__u); } template<typename _Tp, typename _Up> constexpr bool cmp_greater(_Tp __t, _Up __u) noexcept { return std::cmp_less(__u, __t); } template<typename _Tp, typename _Up> constexpr bool cmp_less_equal(_Tp __t, _Up __u) noexcept { return !std::cmp_less(__u, __t); } template<typename _Tp, typename _Up> constexpr bool cmp_greater_equal(_Tp __t, _Up __u) noexcept { return !std::cmp_less(__t, __u); } template<typename _Up, typename _Tp> constexpr bool in_range(_Tp __t) noexcept { static_assert(__is_standard_integer<_Up>::value); static_assert(__is_standard_integer<_Tp>::value); using __gnu_cxx::__int_traits; if constexpr (is_signed_v<_Tp> == is_signed_v<_Up>) return __int_traits<_Up>::__min <= __t && __t <= __int_traits<_Up>::__max; else if constexpr (is_signed_v<_Tp>) return __t >= 0 && make_unsigned_t<_Tp>(__t) <= __int_traits<_Up>::__max; else return __t <= make_unsigned_t<_Up>(__int_traits<_Up>::__max); } #endif // C++20 #endif // C++17 _GLIBCXX_END_NAMESPACE_VERSION } // namespace #endif #endif /* _GLIBCXX_UTILITY */