stl_function.h
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// Functor implementations -*- C++ -*-
// Copyright (C) 2001-2026 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) 1996-1998
* 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_function.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{functional}
*/
#ifndef _STL_FUNCTION_H
#define _STL_FUNCTION_H 1
#if __cplusplus > 201103L
#include <bits/move.h>
#endif
#if __cplusplus >= 202002L
#include <concepts>
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
// 20.3.1 base classes
/** @defgroup functors Function Objects
* @ingroup utilities
*
* Function objects, or _functors_, are objects with an `operator()`
* defined and accessible. They can be passed as arguments to algorithm
* templates and used in place of a function pointer. Not only is the
* resulting expressiveness of the library increased, but the generated
* code can be more efficient than what you might write by hand. When we
* refer to _functors_, then, generally we include function pointers in
* the description as well.
*
* Often, functors are only created as temporaries passed to algorithm
* calls, rather than being created as named variables.
*
* Two examples taken from the standard itself follow. To perform a
* by-element addition of two vectors `a` and `b` containing `double`,
* and put the result in `a`, use
* \code
* transform (a.begin(), a.end(), b.begin(), a.begin(), plus<double>());
* \endcode
* To negate every element in `a`, use
* \code
* transform(a.begin(), a.end(), a.begin(), negate<double>());
* \endcode
* The addition and negation functions will usually be inlined directly.
*
* An _adaptable function object_ is one which provides nested typedefs
* `result_type` and either `argument_type` (for a unary function) or
* `first_argument_type` and `second_argument_type` (for a binary function).
* Those typedefs are used by function object adaptors such as `bind2nd`.
* The standard library provides two class templates, `unary_function` and
* `binary_function`, which define those typedefs and so can be used as
* base classes of adaptable function objects.
*
* Since C++11 the use of function object adaptors has been superseded by
* more powerful tools such as lambda expressions, `function<>`, and more
* powerful type deduction (using `auto` and `decltype`). The helpers for
* defining adaptable function objects are deprecated since C++11, and no
* longer part of the standard library since C++17. However, they are still
* defined and used by libstdc++ after C++17, as a conforming extension.
*
* @{
*/
/**
* Helper for defining adaptable unary function objects.
* @deprecated Deprecated in C++11, no longer in the standard since C++17.
*/
template<typename _Arg, typename _Result>
struct unary_function
{
/// @c argument_type is the type of the argument
typedef _Arg argument_type;
/// @c result_type is the return type
typedef _Result result_type;
} _GLIBCXX11_DEPRECATED;
/**
* Helper for defining adaptable binary function objects.
* @deprecated Deprecated in C++11, no longer in the standard since C++17.
*/
template<typename _Arg1, typename _Arg2, typename _Result>
struct binary_function
{
/// @c first_argument_type is the type of the first argument
typedef _Arg1 first_argument_type;
/// @c second_argument_type is the type of the second argument
typedef _Arg2 second_argument_type;
/// @c result_type is the return type
typedef _Result result_type;
} _GLIBCXX11_DEPRECATED;
/** @} */
// 20.3.2 arithmetic
/** @defgroup arithmetic_functors Arithmetic Function Object Classes
* @ingroup functors
*
* The library provides function objects for basic arithmetic operations.
* See the documentation for @link functors function objects @endlink
* for examples of their use.
*
* @{
*/
#if __glibcxx_transparent_operators // C++ >= 14
struct __is_transparent; // undefined
template<typename _Tp = void>
struct plus;
template<typename _Tp = void>
struct minus;
template<typename _Tp = void>
struct multiplies;
template<typename _Tp = void>
struct divides;
template<typename _Tp = void>
struct modulus;
template<typename _Tp = void>
struct negate;
#endif
// Ignore warnings about unary_function and binary_function.
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
/// One of the @link arithmetic_functors math functors@endlink.
template<typename _Tp>
struct plus : public binary_function<_Tp, _Tp, _Tp>
{
/// Returns the sum
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x + __y; }
};
/// One of the @link arithmetic_functors math functors@endlink.
template<typename _Tp>
struct minus : public binary_function<_Tp, _Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x - __y; }
};
/// One of the @link arithmetic_functors math functors@endlink.
template<typename _Tp>
struct multiplies : public binary_function<_Tp, _Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x * __y; }
};
/// One of the @link arithmetic_functors math functors@endlink.
template<typename _Tp>
struct divides : public binary_function<_Tp, _Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x / __y; }
};
/// One of the @link arithmetic_functors math functors@endlink.
template<typename _Tp>
struct modulus : public binary_function<_Tp, _Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x % __y; }
};
/// One of the @link arithmetic_functors math functors@endlink.
template<typename _Tp>
struct negate : public unary_function<_Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x) const
{ return -__x; }
};
#pragma GCC diagnostic pop
#ifdef __glibcxx_transparent_operators // C++ >= 14
template<>
struct plus<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) + std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) + std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) + std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link arithmetic_functors math functors@endlink.
template<>
struct minus<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) - std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) - std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) - std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link arithmetic_functors math functors@endlink.
template<>
struct multiplies<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) * std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) * std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) * std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link arithmetic_functors math functors@endlink.
template<>
struct divides<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) / std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) / std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) / std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link arithmetic_functors math functors@endlink.
template<>
struct modulus<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) % std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) % std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) % std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link arithmetic_functors math functors@endlink.
template<>
struct negate<void>
{
template <typename _Tp>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t) const
noexcept(noexcept(-std::forward<_Tp>(__t)))
-> decltype(-std::forward<_Tp>(__t))
{ return -std::forward<_Tp>(__t); }
typedef __is_transparent is_transparent;
};
#endif
/** @} */
// 20.3.3 comparisons
/** @defgroup comparison_functors Comparison Classes
* @ingroup functors
*
* The library provides six wrapper functors for all the basic comparisons
* in C++, like @c <.
*
* @{
*/
#if __glibcxx_transparent_operators // C++ >= 14
template<typename _Tp = void>
struct equal_to;
template<typename _Tp = void>
struct not_equal_to;
template<typename _Tp = void>
struct greater;
template<typename _Tp = void>
struct less;
template<typename _Tp = void>
struct greater_equal;
template<typename _Tp = void>
struct less_equal;
#endif
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
/// One of the @link comparison_functors comparison functors@endlink.
template<typename _Tp>
struct equal_to : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x == __y; }
};
/// One of the @link comparison_functors comparison functors@endlink.
template<typename _Tp>
struct not_equal_to : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x != __y; }
};
/// One of the @link comparison_functors comparison functors@endlink.
template<typename _Tp>
struct greater : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x > __y; }
};
/// One of the @link comparison_functors comparison functors@endlink.
template<typename _Tp>
struct less : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x < __y; }
};
/// One of the @link comparison_functors comparison functors@endlink.
template<typename _Tp>
struct greater_equal : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x >= __y; }
};
/// One of the @link comparison_functors comparison functors@endlink.
template<typename _Tp>
struct less_equal : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x <= __y; }
};
// Partial specialization of std::greater for pointers.
template<typename _Tp>
struct greater<_Tp*> : public binary_function<_Tp*, _Tp*, bool>
{
_GLIBCXX14_CONSTEXPR bool
operator()(_Tp* __x, _Tp* __y) const _GLIBCXX_NOTHROW
{
#if __cplusplus >= 201402L
if (std::__is_constant_evaluated())
return __x > __y;
#endif
return (__UINTPTR_TYPE__)__x > (__UINTPTR_TYPE__)__y;
}
};
// Partial specialization of std::less for pointers.
template<typename _Tp>
struct less<_Tp*> : public binary_function<_Tp*, _Tp*, bool>
{
_GLIBCXX14_CONSTEXPR bool
operator()(_Tp* __x, _Tp* __y) const _GLIBCXX_NOTHROW
{
#if __cplusplus >= 201402L
if (std::__is_constant_evaluated())
return __x < __y;
#endif
return (__UINTPTR_TYPE__)__x < (__UINTPTR_TYPE__)__y;
}
};
// Partial specialization of std::greater_equal for pointers.
template<typename _Tp>
struct greater_equal<_Tp*> : public binary_function<_Tp*, _Tp*, bool>
{
_GLIBCXX14_CONSTEXPR bool
operator()(_Tp* __x, _Tp* __y) const _GLIBCXX_NOTHROW
{
#if __cplusplus >= 201402L
if (std::__is_constant_evaluated())
return __x >= __y;
#endif
return (__UINTPTR_TYPE__)__x >= (__UINTPTR_TYPE__)__y;
}
};
// Partial specialization of std::less_equal for pointers.
template<typename _Tp>
struct less_equal<_Tp*> : public binary_function<_Tp*, _Tp*, bool>
{
_GLIBCXX14_CONSTEXPR bool
operator()(_Tp* __x, _Tp* __y) const _GLIBCXX_NOTHROW
{
#if __cplusplus >= 201402L
if (std::__is_constant_evaluated())
return __x <= __y;
#endif
return (__UINTPTR_TYPE__)__x <= (__UINTPTR_TYPE__)__y;
}
};
#pragma GCC diagnostic pop
#ifdef __glibcxx_transparent_operators // C++ >= 14
/// One of the @link comparison_functors comparison functors@endlink.
template<>
struct equal_to<void>
{
template <typename _Tp, typename _Up>
constexpr auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) == std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) == std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) == std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link comparison_functors comparison functors@endlink.
template<>
struct not_equal_to<void>
{
template <typename _Tp, typename _Up>
constexpr auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) != std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) != std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) != std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link comparison_functors comparison functors@endlink.
template<>
struct greater<void>
{
template <typename _Tp, typename _Up>
constexpr auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) > std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) > std::forward<_Up>(__u))
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
if constexpr (__ptr_cmp<_Tp, _Up>)
return greater<const volatile void*>{}(
static_cast<const volatile void*>(std::forward<_Tp>(__t)),
static_cast<const volatile void*>(std::forward<_Up>(__u)));
else
return std::forward<_Tp>(__t) > std::forward<_Up>(__u);
#pragma GCC diagnostic pop
}
template<typename _Tp, typename _Up>
constexpr bool
operator()(_Tp* __t, _Up* __u) const noexcept
{ return greater<common_type_t<_Tp*, _Up*>>{}(__t, __u); }
typedef __is_transparent is_transparent;
private:
#if __cplusplus >= 202002L
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = requires
{
requires
! requires
{ operator>(std::declval<_Tp>(), std::declval<_Up>()); }
&& ! requires
{ std::declval<_Tp>().operator>(std::declval<_Up>()); }
&& __detail::__not_overloaded_spaceship<_Tp, _Up>
&& is_convertible_v<_Tp, const volatile void*>
&& is_convertible_v<_Up, const volatile void*>;
};
#else
// True if there is no viable operator> member function.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded2 : true_type { };
// False if we can call T.operator>(U)
template<typename _Tp, typename _Up>
struct __not_overloaded2<_Tp, _Up, __void_t<
decltype(std::declval<_Tp>().operator>(std::declval<_Up>()))>>
: false_type { };
// True if there is no overloaded operator> for these operands.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded : __not_overloaded2<_Tp, _Up> { };
// False if we can call operator>(T,U)
template<typename _Tp, typename _Up>
struct __not_overloaded<_Tp, _Up, __void_t<
decltype(operator>(std::declval<_Tp>(), std::declval<_Up>()))>>
: false_type { };
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = __and_<
__not_overloaded<_Tp, _Up>,
is_convertible<_Tp, const volatile void*>,
is_convertible<_Up, const volatile void*>>::value;
#endif
};
/// One of the @link comparison_functors comparison functors@endlink.
template<>
struct less<void>
{
template <typename _Tp, typename _Up>
constexpr auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) < std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) < std::forward<_Up>(__u))
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
if constexpr (__ptr_cmp<_Tp, _Up>)
return less<const volatile void*>{}(
static_cast<const volatile void*>(std::forward<_Tp>(__t)),
static_cast<const volatile void*>(std::forward<_Up>(__u)));
else
return std::forward<_Tp>(__t) < std::forward<_Up>(__u);
#pragma GCC diagnostic pop
}
template<typename _Tp, typename _Up>
constexpr bool
operator()(_Tp* __t, _Up* __u) const noexcept
{ return less<common_type_t<_Tp*, _Up*>>{}(__t, __u); }
typedef __is_transparent is_transparent;
private:
#if __cplusplus >= 202002L
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = requires
{
requires
! requires
{ operator<(std::declval<_Tp>(), std::declval<_Up>()); }
&& ! requires
{ std::declval<_Tp>().operator<(std::declval<_Up>()); }
&& __detail::__not_overloaded_spaceship<_Tp, _Up>
&& is_convertible_v<_Tp, const volatile void*>
&& is_convertible_v<_Up, const volatile void*>;
};
#else
// True if there is no viable operator< member function.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded2 : true_type { };
// False if we can call T.operator<(U)
template<typename _Tp, typename _Up>
struct __not_overloaded2<_Tp, _Up, __void_t<
decltype(std::declval<_Tp>().operator<(std::declval<_Up>()))>>
: false_type { };
// True if there is no overloaded operator< for these operands.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded : __not_overloaded2<_Tp, _Up> { };
// False if we can call operator<(T,U)
template<typename _Tp, typename _Up>
struct __not_overloaded<_Tp, _Up, __void_t<
decltype(operator<(std::declval<_Tp>(), std::declval<_Up>()))>>
: false_type { };
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = __and_<
__not_overloaded<_Tp, _Up>,
is_convertible<_Tp, const volatile void*>,
is_convertible<_Up, const volatile void*>>::value;
#endif
};
/// One of the @link comparison_functors comparison functors@endlink.
template<>
struct greater_equal<void>
{
template <typename _Tp, typename _Up>
constexpr auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) >= std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) >= std::forward<_Up>(__u))
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
if constexpr (__ptr_cmp<_Tp, _Up>)
return greater_equal<const volatile void*>{}(
static_cast<const volatile void*>(std::forward<_Tp>(__t)),
static_cast<const volatile void*>(std::forward<_Up>(__u)));
else
return std::forward<_Tp>(__t) >= std::forward<_Up>(__u);
#pragma GCC diagnostic pop
}
template<typename _Tp, typename _Up>
constexpr bool
operator()(_Tp* __t, _Up* __u) const noexcept
{ return greater_equal<common_type_t<_Tp*, _Up*>>{}(__t, __u); }
typedef __is_transparent is_transparent;
private:
#if __cplusplus >= 202002L
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = requires
{
requires
! requires
{ operator>=(std::declval<_Tp>(), std::declval<_Up>()); }
&& ! requires
{ std::declval<_Tp>().operator>=(std::declval<_Up>()); }
&& __detail::__not_overloaded_spaceship<_Tp, _Up>
&& is_convertible_v<_Tp, const volatile void*>
&& is_convertible_v<_Up, const volatile void*>;
};
#else
// True if there is no viable operator>= member function.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded2 : true_type { };
// False if we can call T.operator>=(U)
template<typename _Tp, typename _Up>
struct __not_overloaded2<_Tp, _Up, __void_t<
decltype(std::declval<_Tp>().operator>=(std::declval<_Up>()))>>
: false_type { };
// True if there is no overloaded operator>= for these operands.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded : __not_overloaded2<_Tp, _Up> { };
// False if we can call operator>=(T,U)
template<typename _Tp, typename _Up>
struct __not_overloaded<_Tp, _Up, __void_t<
decltype(operator>=(std::declval<_Tp>(), std::declval<_Up>()))>>
: false_type { };
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = __and_<
__not_overloaded<_Tp, _Up>,
is_convertible<_Tp, const volatile void*>,
is_convertible<_Up, const volatile void*>>::value;
#endif
};
/// One of the @link comparison_functors comparison functors@endlink.
template<>
struct less_equal<void>
{
template <typename _Tp, typename _Up>
constexpr auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) <= std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) <= std::forward<_Up>(__u))
{
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
if constexpr (__ptr_cmp<_Tp, _Up>)
return less_equal<const volatile void*>{}(
static_cast<const volatile void*>(std::forward<_Tp>(__t)),
static_cast<const volatile void*>(std::forward<_Up>(__u)));
else
return std::forward<_Tp>(__t) <= std::forward<_Up>(__u);
#pragma GCC diagnostic pop
}
template<typename _Tp, typename _Up>
constexpr bool
operator()(_Tp* __t, _Up* __u) const noexcept
{ return less_equal<common_type_t<_Tp*, _Up*>>{}(__t, __u); }
typedef __is_transparent is_transparent;
private:
#if __cplusplus >= 202002L
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = requires
{
requires
! requires
{ operator<=(std::declval<_Tp>(), std::declval<_Up>()); }
&& ! requires
{ std::declval<_Tp>().operator<=(std::declval<_Up>()); }
&& __detail::__not_overloaded_spaceship<_Tp, _Up>
&& is_convertible_v<_Tp, const volatile void*>
&& is_convertible_v<_Up, const volatile void*>;
};
#else
// True if there is no viable operator<= member function.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded2 : true_type { };
// False if we can call T.operator<=(U)
template<typename _Tp, typename _Up>
struct __not_overloaded2<_Tp, _Up, __void_t<
decltype(std::declval<_Tp>().operator<=(std::declval<_Up>()))>>
: false_type { };
// True if there is no overloaded operator<= for these operands.
template<typename _Tp, typename _Up, typename = void>
struct __not_overloaded : __not_overloaded2<_Tp, _Up> { };
// False if we can call operator<=(T,U)
template<typename _Tp, typename _Up>
struct __not_overloaded<_Tp, _Up, __void_t<
decltype(operator<=(std::declval<_Tp>(), std::declval<_Up>()))>>
: false_type { };
template<typename _Tp, typename _Up>
static constexpr bool __ptr_cmp = __and_<
__not_overloaded<_Tp, _Up>,
is_convertible<_Tp, const volatile void*>,
is_convertible<_Up, const volatile void*>>::value;
#endif
};
#else // < C++14
// We need less<void> and equal_to<void> for <bits/predefined_ops.h>
template<>
struct equal_to<void>
{
#ifdef __cpp_rvalue_references
template<typename _Tp, typename _Up>
bool
operator()(_Tp&& __t, _Up&& __u) const
{ return __t == __u; }
#else // C++98
template<typename _Tp, typename _Up>
bool
operator()(_Tp& __t, _Up& __u) const { return __t == __u; }
template<typename _Tp, typename _Up>
bool
operator()(const _Tp& __t, _Up& __u) const { return __t == __u; }
template<typename _Tp, typename _Up>
bool
operator()(_Tp& __t, const _Up& __u) const { return __t == __u; }
template<typename _Tp, typename _Up>
bool
operator()(const _Tp& __t, const _Up& __u) const { return __t == __u; }
#endif
};
template<>
struct less<void>
{
#ifdef __cpp_rvalue_references
template<typename _Tp, typename _Up>
bool
operator()(_Tp&& __t, _Up&& __u) const
{ return __t < __u; }
#else // C++98
template<typename _Tp, typename _Up>
bool
operator()(_Tp& __t, _Up& __u) const { return __t < __u; }
template<typename _Tp, typename _Up>
bool
operator()(const _Tp& __t, _Up& __u) const { return __t < __u; }
template<typename _Tp, typename _Up>
bool
operator()(_Tp& __t, const _Up& __u) const { return __t < __u; }
template<typename _Tp, typename _Up>
bool
operator()(const _Tp& __t, const _Up& __u) const { return __t < __u; }
#endif
};
#endif // __glibcxx_transparent_operators
/** @} */
// 20.3.4 logical operations
/** @defgroup logical_functors Boolean Operations Classes
* @ingroup functors
*
* The library provides function objects for the logical operations:
* `&&`, `||`, and `!`.
*
* @{
*/
#ifdef __glibcxx_transparent_operators // C++ >= 14
template<typename _Tp = void>
struct logical_and;
template<typename _Tp = void>
struct logical_or;
template<typename _Tp = void>
struct logical_not;
#endif
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
/// One of the @link logical_functors Boolean operations functors@endlink.
template<typename _Tp>
struct logical_and : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x && __y; }
};
/// One of the @link logical_functors Boolean operations functors@endlink.
template<typename _Tp>
struct logical_or : public binary_function<_Tp, _Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x || __y; }
};
/// One of the @link logical_functors Boolean operations functors@endlink.
template<typename _Tp>
struct logical_not : public unary_function<_Tp, bool>
{
_GLIBCXX14_CONSTEXPR
bool
operator()(const _Tp& __x) const
{ return !__x; }
};
#pragma GCC diagnostic pop
#ifdef __glibcxx_transparent_operators // C++ >= 14
/// One of the @link logical_functors Boolean operations functors@endlink.
template<>
struct logical_and<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) && std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) && std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) && std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link logical_functors Boolean operations functors@endlink.
template<>
struct logical_or<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) || std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) || std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) || std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
/// One of the @link logical_functors Boolean operations functors@endlink.
template<>
struct logical_not<void>
{
template <typename _Tp>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t) const
noexcept(noexcept(!std::forward<_Tp>(__t)))
-> decltype(!std::forward<_Tp>(__t))
{ return !std::forward<_Tp>(__t); }
typedef __is_transparent is_transparent;
};
#endif // __glibcxx_transparent_operators
/** @} */
#ifdef __glibcxx_transparent_operators // C++ >= 14
template<typename _Tp = void>
struct bit_and;
template<typename _Tp = void>
struct bit_or;
template<typename _Tp = void>
struct bit_xor;
template<typename _Tp = void>
struct bit_not;
#endif
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 660. Missing Bitwise Operations.
template<typename _Tp>
struct bit_and : public binary_function<_Tp, _Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x & __y; }
};
template<typename _Tp>
struct bit_or : public binary_function<_Tp, _Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x | __y; }
};
template<typename _Tp>
struct bit_xor : public binary_function<_Tp, _Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x, const _Tp& __y) const
{ return __x ^ __y; }
};
template<typename _Tp>
struct bit_not : public unary_function<_Tp, _Tp>
{
_GLIBCXX14_CONSTEXPR
_Tp
operator()(const _Tp& __x) const
{ return ~__x; }
};
#pragma GCC diagnostic pop
#ifdef __glibcxx_transparent_operators // C++ >= 14
template <>
struct bit_and<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) & std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) & std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) & std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
template <>
struct bit_or<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) | std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) | std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) | std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
template <>
struct bit_xor<void>
{
template <typename _Tp, typename _Up>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t, _Up&& __u) const
noexcept(noexcept(std::forward<_Tp>(__t) ^ std::forward<_Up>(__u)))
-> decltype(std::forward<_Tp>(__t) ^ std::forward<_Up>(__u))
{ return std::forward<_Tp>(__t) ^ std::forward<_Up>(__u); }
typedef __is_transparent is_transparent;
};
template <>
struct bit_not<void>
{
template <typename _Tp>
_GLIBCXX14_CONSTEXPR
auto
operator()(_Tp&& __t) const
noexcept(noexcept(~std::forward<_Tp>(__t)))
-> decltype(~std::forward<_Tp>(__t))
{ return ~std::forward<_Tp>(__t); }
typedef __is_transparent is_transparent;
};
#endif // C++14
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
// 20.3.5 negators
/** @defgroup negators Negators
* @ingroup functors
*
* The function templates `not1` and `not2` are function object adaptors,
* which each take a predicate functor and wrap it in an instance of
* `unary_negate` or `binary_negate`, respectively. Those classes are
* functors whose `operator()` evaluates the wrapped predicate function
* and then returns the negation of the result.
*
* For example, given a vector of integers and a trivial predicate,
* \code
* struct IntGreaterThanThree
* : public std::unary_function<int, bool>
* {
* bool operator() (int x) const { return x > 3; }
* };
*
* std::find_if (v.begin(), v.end(), not1(IntGreaterThanThree()));
* \endcode
* The call to `find_if` will locate the first index (i) of `v` for which
* `!(v[i] > 3)` is true.
*
* The not1/unary_negate combination works on predicates taking a single
* argument. The not2/binary_negate combination works on predicates taking
* two arguments.
*
* @deprecated Deprecated in C++17, no longer in the standard since C++20.
* Use `not_fn` instead.
*
* @{
*/
/// One of the @link negators negation functors@endlink.
template<typename _Predicate>
class _GLIBCXX17_DEPRECATED unary_negate
: public unary_function<typename _Predicate::argument_type, bool>
{
protected:
_Predicate _M_pred;
public:
_GLIBCXX14_CONSTEXPR
explicit
unary_negate(const _Predicate& __x) : _M_pred(__x) { }
_GLIBCXX14_CONSTEXPR
bool
operator()(const typename _Predicate::argument_type& __x) const
{ return !_M_pred(__x); }
};
/// One of the @link negators negation functors@endlink.
template<typename _Predicate>
_GLIBCXX17_DEPRECATED_SUGGEST("std::not_fn")
_GLIBCXX14_CONSTEXPR
inline unary_negate<_Predicate>
not1(const _Predicate& __pred)
{ return unary_negate<_Predicate>(__pred); }
/// One of the @link negators negation functors@endlink.
template<typename _Predicate>
class _GLIBCXX17_DEPRECATED binary_negate
: public binary_function<typename _Predicate::first_argument_type,
typename _Predicate::second_argument_type, bool>
{
protected:
_Predicate _M_pred;
public:
_GLIBCXX14_CONSTEXPR
explicit
binary_negate(const _Predicate& __x) : _M_pred(__x) { }
_GLIBCXX14_CONSTEXPR
bool
operator()(const typename _Predicate::first_argument_type& __x,
const typename _Predicate::second_argument_type& __y) const
{ return !_M_pred(__x, __y); }
};
/// One of the @link negators negation functors@endlink.
template<typename _Predicate>
_GLIBCXX17_DEPRECATED_SUGGEST("std::not_fn")
_GLIBCXX14_CONSTEXPR
inline binary_negate<_Predicate>
not2(const _Predicate& __pred)
{ return binary_negate<_Predicate>(__pred); }
/** @} */
// 20.3.7 adaptors pointers functions
/** @defgroup pointer_adaptors Adaptors for pointers to functions
* @ingroup functors
*
* The advantage of function objects over pointers to functions is that
* the objects in the standard library declare nested typedefs describing
* their argument and result types with uniform names (e.g., `result_type`
* from the base classes `unary_function` and `binary_function`).
* Sometimes those typedefs are required, not just optional.
*
* Adaptors are provided to turn pointers to unary (single-argument) and
* binary (double-argument) functions into function objects. The
* long-winded functor `pointer_to_unary_function` is constructed with a
* function pointer `f`, and its `operator()` called with argument `x`
* returns `f(x)`. The functor `pointer_to_binary_function` does the same
* thing, but with a double-argument `f` and `operator()`.
*
* The function `ptr_fun` takes a pointer-to-function `f` and constructs
* an instance of the appropriate functor.
*
* @deprecated Deprecated in C++11, no longer in the standard since C++17.
*
* @{
*/
/// One of the @link pointer_adaptors adaptors for function pointers@endlink.
template<typename _Arg, typename _Result>
class pointer_to_unary_function : public unary_function<_Arg, _Result>
{
protected:
_Result (*_M_ptr)(_Arg);
public:
pointer_to_unary_function() { }
explicit
pointer_to_unary_function(_Result (*__x)(_Arg))
: _M_ptr(__x) { }
_Result
operator()(_Arg __x) const
{ return _M_ptr(__x); }
} _GLIBCXX11_DEPRECATED;
/// One of the @link pointer_adaptors adaptors for function pointers@endlink.
template<typename _Arg, typename _Result>
_GLIBCXX11_DEPRECATED_SUGGEST("std::function")
inline pointer_to_unary_function<_Arg, _Result>
ptr_fun(_Result (*__x)(_Arg))
{ return pointer_to_unary_function<_Arg, _Result>(__x); }
/// One of the @link pointer_adaptors adaptors for function pointers@endlink.
template<typename _Arg1, typename _Arg2, typename _Result>
class pointer_to_binary_function
: public binary_function<_Arg1, _Arg2, _Result>
{
protected:
_Result (*_M_ptr)(_Arg1, _Arg2);
public:
pointer_to_binary_function() { }
explicit
pointer_to_binary_function(_Result (*__x)(_Arg1, _Arg2))
: _M_ptr(__x) { }
_Result
operator()(_Arg1 __x, _Arg2 __y) const
{ return _M_ptr(__x, __y); }
} _GLIBCXX11_DEPRECATED;
/// One of the @link pointer_adaptors adaptors for function pointers@endlink.
template<typename _Arg1, typename _Arg2, typename _Result>
_GLIBCXX11_DEPRECATED_SUGGEST("std::function")
inline pointer_to_binary_function<_Arg1, _Arg2, _Result>
ptr_fun(_Result (*__x)(_Arg1, _Arg2))
{ return pointer_to_binary_function<_Arg1, _Arg2, _Result>(__x); }
/** @} */
template<typename _Tp>
struct _Identity
: public unary_function<_Tp, _Tp>
{
_Tp&
operator()(_Tp& __x) const
{ return __x; }
const _Tp&
operator()(const _Tp& __x) const
{ return __x; }
};
// Partial specialization, avoids confusing errors in e.g. std::set<const T>.
template<typename _Tp> struct _Identity<const _Tp> : _Identity<_Tp> { };
template<typename _Pair>
struct _Select1st
: public unary_function<_Pair, typename _Pair::first_type>
{
typename _Pair::first_type&
operator()(_Pair& __x) const
{ return __x.first; }
const typename _Pair::first_type&
operator()(const _Pair& __x) const
{ return __x.first; }
#if __cplusplus >= 201103L
template<typename _Pair2>
typename _Pair2::first_type&
operator()(_Pair2& __x) const
{ return __x.first; }
template<typename _Pair2>
const typename _Pair2::first_type&
operator()(const _Pair2& __x) const
{ return __x.first; }
#endif
};
template<typename _Pair>
struct _Select2nd
: public unary_function<_Pair, typename _Pair::second_type>
{
typename _Pair::second_type&
operator()(_Pair& __x) const
{ return __x.second; }
const typename _Pair::second_type&
operator()(const _Pair& __x) const
{ return __x.second; }
};
// 20.3.8 adaptors pointers members
/** @defgroup ptrmem_adaptors Adaptors for pointers to members
* @ingroup functors
*
* There are a total of 8 = 2^3 function objects in this family.
* (1) Member functions taking no arguments vs member functions taking
* one argument.
* (2) Call through pointer vs call through reference.
* (3) Const vs non-const member function.
*
* All of this complexity is in the function objects themselves. You can
* ignore it by using the helper function `mem_fun` and `mem_fun_ref`,
* which create whichever type of adaptor is appropriate.
*
* @deprecated Deprecated in C++11, no longer in the standard since C++17.
* Use `mem_fn` instead.
*
* @{
*/
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp>
class mem_fun_t : public unary_function<_Tp*, _Ret>
{
public:
explicit
mem_fun_t(_Ret (_Tp::*__pf)())
: _M_f(__pf) { }
_Ret
operator()(_Tp* __p) const
{ return (__p->*_M_f)(); }
private:
_Ret (_Tp::*_M_f)();
} _GLIBCXX11_DEPRECATED;
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp>
class const_mem_fun_t : public unary_function<const _Tp*, _Ret>
{
public:
explicit
const_mem_fun_t(_Ret (_Tp::*__pf)() const)
: _M_f(__pf) { }
_Ret
operator()(const _Tp* __p) const
{ return (__p->*_M_f)(); }
private:
_Ret (_Tp::*_M_f)() const;
} _GLIBCXX11_DEPRECATED;
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp>
class mem_fun_ref_t : public unary_function<_Tp, _Ret>
{
public:
explicit
mem_fun_ref_t(_Ret (_Tp::*__pf)())
: _M_f(__pf) { }
_Ret
operator()(_Tp& __r) const
{ return (__r.*_M_f)(); }
private:
_Ret (_Tp::*_M_f)();
} _GLIBCXX11_DEPRECATED;
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp>
class const_mem_fun_ref_t : public unary_function<_Tp, _Ret>
{
public:
explicit
const_mem_fun_ref_t(_Ret (_Tp::*__pf)() const)
: _M_f(__pf) { }
_Ret
operator()(const _Tp& __r) const
{ return (__r.*_M_f)(); }
private:
_Ret (_Tp::*_M_f)() const;
} _GLIBCXX11_DEPRECATED;
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp, typename _Arg>
class mem_fun1_t : public binary_function<_Tp*, _Arg, _Ret>
{
public:
explicit
mem_fun1_t(_Ret (_Tp::*__pf)(_Arg))
: _M_f(__pf) { }
_Ret
operator()(_Tp* __p, _Arg __x) const
{ return (__p->*_M_f)(__x); }
private:
_Ret (_Tp::*_M_f)(_Arg);
} _GLIBCXX11_DEPRECATED;
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp, typename _Arg>
class const_mem_fun1_t : public binary_function<const _Tp*, _Arg, _Ret>
{
public:
explicit
const_mem_fun1_t(_Ret (_Tp::*__pf)(_Arg) const)
: _M_f(__pf) { }
_Ret
operator()(const _Tp* __p, _Arg __x) const
{ return (__p->*_M_f)(__x); }
private:
_Ret (_Tp::*_M_f)(_Arg) const;
} _GLIBCXX11_DEPRECATED;
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp, typename _Arg>
class mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
{
public:
explicit
mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg))
: _M_f(__pf) { }
_Ret
operator()(_Tp& __r, _Arg __x) const
{ return (__r.*_M_f)(__x); }
private:
_Ret (_Tp::*_M_f)(_Arg);
} _GLIBCXX11_DEPRECATED;
/// One of the @link ptrmem_adaptors adaptors for member pointers@endlink.
template<typename _Ret, typename _Tp, typename _Arg>
class const_mem_fun1_ref_t : public binary_function<_Tp, _Arg, _Ret>
{
public:
explicit
const_mem_fun1_ref_t(_Ret (_Tp::*__pf)(_Arg) const)
: _M_f(__pf) { }
_Ret
operator()(const _Tp& __r, _Arg __x) const
{ return (__r.*_M_f)(__x); }
private:
_Ret (_Tp::*_M_f)(_Arg) const;
} _GLIBCXX11_DEPRECATED;
// Mem_fun adaptor helper functions. There are only two:
// mem_fun and mem_fun_ref.
template<typename _Ret, typename _Tp>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline mem_fun_t<_Ret, _Tp>
mem_fun(_Ret (_Tp::*__f)())
{ return mem_fun_t<_Ret, _Tp>(__f); }
template<typename _Ret, typename _Tp>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline const_mem_fun_t<_Ret, _Tp>
mem_fun(_Ret (_Tp::*__f)() const)
{ return const_mem_fun_t<_Ret, _Tp>(__f); }
template<typename _Ret, typename _Tp>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline mem_fun_ref_t<_Ret, _Tp>
mem_fun_ref(_Ret (_Tp::*__f)())
{ return mem_fun_ref_t<_Ret, _Tp>(__f); }
template<typename _Ret, typename _Tp>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline const_mem_fun_ref_t<_Ret, _Tp>
mem_fun_ref(_Ret (_Tp::*__f)() const)
{ return const_mem_fun_ref_t<_Ret, _Tp>(__f); }
template<typename _Ret, typename _Tp, typename _Arg>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline mem_fun1_t<_Ret, _Tp, _Arg>
mem_fun(_Ret (_Tp::*__f)(_Arg))
{ return mem_fun1_t<_Ret, _Tp, _Arg>(__f); }
template<typename _Ret, typename _Tp, typename _Arg>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline const_mem_fun1_t<_Ret, _Tp, _Arg>
mem_fun(_Ret (_Tp::*__f)(_Arg) const)
{ return const_mem_fun1_t<_Ret, _Tp, _Arg>(__f); }
template<typename _Ret, typename _Tp, typename _Arg>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline mem_fun1_ref_t<_Ret, _Tp, _Arg>
mem_fun_ref(_Ret (_Tp::*__f)(_Arg))
{ return mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); }
template<typename _Ret, typename _Tp, typename _Arg>
_GLIBCXX11_DEPRECATED_SUGGEST("std::mem_fn")
inline const_mem_fun1_ref_t<_Ret, _Tp, _Arg>
mem_fun_ref(_Ret (_Tp::*__f)(_Arg) const)
{ return const_mem_fun1_ref_t<_Ret, _Tp, _Arg>(__f); }
#pragma GCC diagnostic pop
/** @} */
#ifdef __glibcxx_transparent_operators // C++ >= 14
template<typename _Func, typename _SfinaeType, typename = __void_t<>>
struct __has_is_transparent
{ };
template<typename _Func, typename _SfinaeType>
struct __has_is_transparent<_Func, _SfinaeType,
__void_t<typename _Func::is_transparent>>
{ typedef void type; };
template<typename _Func, typename _SfinaeType>
using __has_is_transparent_t
= typename __has_is_transparent<_Func, _SfinaeType>::type;
#if __cpp_concepts
template<typename _Func>
concept __transparent_comparator
= requires { typename _Func::is_transparent; };
#endif
#endif
#ifdef __glibcxx_associative_heterogeneous_erasure // C++ >= 23
template <typename _Kt, typename _Container>
concept __not_container_iterator =
(!is_convertible_v<_Kt&&, typename _Container::iterator> &&
!is_convertible_v<_Kt&&, typename _Container::const_iterator>);
template <typename _Kt, typename _Container>
concept __heterogeneous_key =
(!is_same_v<typename _Container::key_type, remove_cvref_t<_Kt>>) &&
__not_container_iterator<_Kt, _Container>;
#endif
#if __cplusplus > 201703L
template<template<typename> class>
constexpr bool __is_std_op_template = false;
template<>
inline constexpr bool __is_std_op_template<std::equal_to> = true;
template<>
inline constexpr bool __is_std_op_template<std::not_equal_to> = true;
template<>
inline constexpr bool __is_std_op_template<std::greater> = true;
template<>
inline constexpr bool __is_std_op_template<std::less> = true;
template<>
inline constexpr bool __is_std_op_template<std::greater_equal> = true;
template<>
inline constexpr bool __is_std_op_template<std::less_equal> = true;
template<>
inline constexpr bool __is_std_op_template<std::plus> = true;
template<>
inline constexpr bool __is_std_op_template<std::minus> = true;
template<>
inline constexpr bool __is_std_op_template<std::multiplies> = true;
template<>
inline constexpr bool __is_std_op_template<std::divides> = true;
template<>
inline constexpr bool __is_std_op_template<std::modulus> = true;
template<>
inline constexpr bool __is_std_op_template<std::negate> = true;
template<>
inline constexpr bool __is_std_op_template<std::logical_and> = true;
template<>
inline constexpr bool __is_std_op_template<std::logical_or> = true;
template<>
inline constexpr bool __is_std_op_template<std::logical_not> = true;
template<>
inline constexpr bool __is_std_op_template<std::bit_and> = true;
template<>
inline constexpr bool __is_std_op_template<std::bit_or> = true;
template<>
inline constexpr bool __is_std_op_template<std::bit_xor> = true;
template<>
inline constexpr bool __is_std_op_template<std::bit_not> = true;
template<typename _Fn>
constexpr bool __is_std_op_wrapper = false;
template<template<typename> class _Ft, typename _Tp>
constexpr bool __is_std_op_wrapper<_Ft<_Tp>>
= __is_std_op_template<_Ft>;
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#if (__cplusplus < 201103L) || _GLIBCXX_USE_DEPRECATED
# include <backward/binders.h>
#endif
#endif /* _STL_FUNCTION_H */
concepts
move.h
std::true_type
__bool_constant< true > true_type
The type used as a compile-time boolean with true value.
Definition type_traits:119
std::false_type
__bool_constant< false > false_type
The type used as a compile-time boolean with false value.
Definition type_traits:122
std::declval
auto declval() noexcept -> decltype(__declval< _Tp >(0))
Definition type_traits:2718
std::forward
constexpr _Tp && forward(typename std::remove_reference< _Tp >::type &__t) noexcept
Forward an lvalue.
Definition move.h:72
std::not2
constexpr binary_negate< _Predicate > not2(const _Predicate &__pred)
One of the negation functors.
Definition stl_function.h:1163
std::not1
constexpr unary_negate< _Predicate > not1(const _Predicate &__pred)
One of the negation functors.
Definition stl_function.h:1134
std::ptr_fun
pointer_to_unary_function< _Arg, _Result > ptr_fun(_Result(*__x)(_Arg))
One of the adaptors for function pointers.
Definition stl_function.h:1214
std
ISO C++ entities toplevel namespace is std.
std::unary_function
Definition stl_function.h:121
std::unary_function::argument_type
_Arg argument_type
argument_type is the type of the argument
Definition stl_function.h:123
std::unary_function::result_type
_Result result_type
result_type is the return type
Definition stl_function.h:126
std::binary_function
Definition stl_function.h:135
std::binary_function::result_type
_Result result_type
result_type is the return type
Definition stl_function.h:143
std::binary_function::second_argument_type
_Arg2 second_argument_type
second_argument_type is the type of the second argument
Definition stl_function.h:140
std::binary_function::first_argument_type
_Arg1 first_argument_type
first_argument_type is the type of the first argument
Definition stl_function.h:137
std::plus
One of the math functors.
Definition stl_function.h:188
std::plus::operator()
constexpr _Tp operator()(const _Tp &__x, const _Tp &__y) const
Returns the sum.
Definition stl_function.h:192
std::minus
One of the math functors.
Definition stl_function.h:199
std::multiplies
One of the math functors.
Definition stl_function.h:209
std::divides
One of the math functors.
Definition stl_function.h:219
std::modulus
One of the math functors.
Definition stl_function.h:229
std::negate
One of the math functors.
Definition stl_function.h:239
std::equal_to
One of the comparison functors.
Definition stl_function.h:374
std::not_equal_to
One of the comparison functors.
Definition stl_function.h:384
std::greater
One of the comparison functors.
Definition stl_function.h:394
std::less
One of the comparison functors.
Definition stl_function.h:404
std::greater_equal
One of the comparison functors.
Definition stl_function.h:414
std::less_equal
One of the comparison functors.
Definition stl_function.h:424
std::logical_and
One of the Boolean operations functors.
Definition stl_function.h:885
std::logical_or
One of the Boolean operations functors.
Definition stl_function.h:895
std::logical_not
One of the Boolean operations functors.
Definition stl_function.h:905
std::unary_negate
One of the negation functors.
Definition stl_function.h:1114
std::binary_negate
One of the negation functors.
Definition stl_function.h:1142
std::pointer_to_unary_function
One of the adaptors for function pointers.
Definition stl_function.h:1194
std::pointer_to_binary_function
One of the adaptors for function pointers.
Definition stl_function.h:1221
std::mem_fun_t
One of the adaptors for member pointers.
Definition stl_function.h:1321
std::mem_fun_ref_t
One of the adaptors for member pointers.
Definition stl_function.h:1355
std::const_mem_fun_ref_t
One of the adaptors for member pointers.
Definition stl_function.h:1372
std::mem_fun1_t
One of the adaptors for member pointers.
Definition stl_function.h:1389
std::const_mem_fun1_t
One of the adaptors for member pointers.
Definition stl_function.h:1406
std::mem_fun1_ref_t
One of the adaptors for member pointers.
Definition stl_function.h:1423
std::const_mem_fun1_ref_t
One of the adaptors for member pointers.
Definition stl_function.h:1440
binders.h