functional
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// <functional> -*- C++ -*-
// Copyright (C) 2001-2015 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) 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/functional
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_FUNCTIONAL
#define _GLIBCXX_FUNCTIONAL 1
#pragma GCC system_header
#include <bits/c++config.h>
#include <bits/stl_function.h>
#if __cplusplus >= 201103L
#include <typeinfo>
#include <new>
#include <tuple>
#include <type_traits>
#include <bits/functexcept.h>
#include <bits/functional_hash.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _MemberPointer>
class _Mem_fn;
template<typename _Tp, typename _Class>
_Mem_fn<_Tp _Class::*>
mem_fn(_Tp _Class::*) noexcept;
/// If we have found a result_type, extract it.
template<typename _Functor, typename = __void_t<>>
struct _Maybe_get_result_type
{ };
template<typename _Functor>
struct _Maybe_get_result_type<_Functor,
__void_t<typename _Functor::result_type>>
{ typedef typename _Functor::result_type result_type; };
/**
* Base class for any function object that has a weak result type, as
* defined in 20.8.2 [func.require] of C++11.
*/
template<typename _Functor>
struct _Weak_result_type_impl
: _Maybe_get_result_type<_Functor>
{ };
/// Retrieve the result type for a function type.
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...)>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......)>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...) const>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......) const>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...) volatile>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......) volatile>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes...) const volatile>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(_ArgTypes......) const volatile>
{ typedef _Res result_type; };
/// Retrieve the result type for a function reference.
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(&)(_ArgTypes...)>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(&)(_ArgTypes......)>
{ typedef _Res result_type; };
/// Retrieve the result type for a function pointer.
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(*)(_ArgTypes...)>
{ typedef _Res result_type; };
template<typename _Res, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res(*)(_ArgTypes......)>
{ typedef _Res result_type; };
/// Retrieve result type for a member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)>
{ typedef _Res result_type; };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)>
{ typedef _Res result_type; };
/// Retrieve result type for a const member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) const>
{ typedef _Res result_type; };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) const>
{ typedef _Res result_type; };
/// Retrieve result type for a volatile member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...) volatile>
{ typedef _Res result_type; };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......) volatile>
{ typedef _Res result_type; };
/// Retrieve result type for a const volatile member function pointer.
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes...)
const volatile>
{ typedef _Res result_type; };
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Weak_result_type_impl<_Res (_Class::*)(_ArgTypes......)
const volatile>
{ typedef _Res result_type; };
/**
* Strip top-level cv-qualifiers from the function object and let
* _Weak_result_type_impl perform the real work.
*/
template<typename _Functor>
struct _Weak_result_type
: _Weak_result_type_impl<typename remove_cv<_Functor>::type>
{ };
/**
* Invoke a function object, which may be either a member pointer or a
* function object. The first parameter will tell which.
*/
template<typename _Functor, typename... _Args>
inline
typename enable_if<
(!is_member_pointer<_Functor>::value
&& !is_function<_Functor>::value
&& !is_function<typename remove_pointer<_Functor>::type>::value),
typename result_of<_Functor&(_Args&&...)>::type
>::type
__invoke(_Functor& __f, _Args&&... __args)
{
return __f(std::forward<_Args>(__args)...);
}
template<typename _Functor, typename... _Args>
inline
typename enable_if<
(is_member_pointer<_Functor>::value
&& !is_function<_Functor>::value
&& !is_function<typename remove_pointer<_Functor>::type>::value),
typename result_of<_Functor(_Args&&...)>::type
>::type
__invoke(_Functor& __f, _Args&&... __args)
{
return std::mem_fn(__f)(std::forward<_Args>(__args)...);
}
// To pick up function references (that will become function pointers)
template<typename _Functor, typename... _Args>
inline
typename enable_if<
(is_pointer<_Functor>::value
&& is_function<typename remove_pointer<_Functor>::type>::value),
typename result_of<_Functor(_Args&&...)>::type
>::type
__invoke(_Functor __f, _Args&&... __args)
{
return __f(std::forward<_Args>(__args)...);
}
/**
* Knowing which of unary_function and binary_function _Tp derives
* from, derives from the same and ensures that reference_wrapper
* will have a weak result type. See cases below.
*/
template<bool _Unary, bool _Binary, typename _Tp>
struct _Reference_wrapper_base_impl;
// None of the nested argument types.
template<typename _Tp>
struct _Reference_wrapper_base_impl<false, false, _Tp>
: _Weak_result_type<_Tp>
{ };
// Nested argument_type only.
template<typename _Tp>
struct _Reference_wrapper_base_impl<true, false, _Tp>
: _Weak_result_type<_Tp>
{
typedef typename _Tp::argument_type argument_type;
};
// Nested first_argument_type and second_argument_type only.
template<typename _Tp>
struct _Reference_wrapper_base_impl<false, true, _Tp>
: _Weak_result_type<_Tp>
{
typedef typename _Tp::first_argument_type first_argument_type;
typedef typename _Tp::second_argument_type second_argument_type;
};
// All the nested argument types.
template<typename _Tp>
struct _Reference_wrapper_base_impl<true, true, _Tp>
: _Weak_result_type<_Tp>
{
typedef typename _Tp::argument_type argument_type;
typedef typename _Tp::first_argument_type first_argument_type;
typedef typename _Tp::second_argument_type second_argument_type;
};
_GLIBCXX_HAS_NESTED_TYPE(argument_type)
_GLIBCXX_HAS_NESTED_TYPE(first_argument_type)
_GLIBCXX_HAS_NESTED_TYPE(second_argument_type)
/**
* Derives from unary_function or binary_function when it
* can. Specializations handle all of the easy cases. The primary
* template determines what to do with a class type, which may
* derive from both unary_function and binary_function.
*/
template<typename _Tp>
struct _Reference_wrapper_base
: _Reference_wrapper_base_impl<
__has_argument_type<_Tp>::value,
__has_first_argument_type<_Tp>::value
&& __has_second_argument_type<_Tp>::value,
_Tp>
{ };
// - a function type (unary)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(_T1)>
: unary_function<_T1, _Res>
{ };
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(_T1) const>
: unary_function<_T1, _Res>
{ };
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(_T1) volatile>
: unary_function<_T1, _Res>
{ };
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(_T1) const volatile>
: unary_function<_T1, _Res>
{ };
// - a function type (binary)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(_T1, _T2)>
: binary_function<_T1, _T2, _Res>
{ };
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(_T1, _T2) const>
: binary_function<_T1, _T2, _Res>
{ };
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(_T1, _T2) volatile>
: binary_function<_T1, _T2, _Res>
{ };
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(_T1, _T2) const volatile>
: binary_function<_T1, _T2, _Res>
{ };
// - a function pointer type (unary)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res(*)(_T1)>
: unary_function<_T1, _Res>
{ };
// - a function pointer type (binary)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res(*)(_T1, _T2)>
: binary_function<_T1, _T2, _Res>
{ };
// - a pointer to member function type (unary, no qualifiers)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)()>
: unary_function<_T1*, _Res>
{ };
// - a pointer to member function type (binary, no qualifiers)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2)>
: binary_function<_T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, const)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() const>
: unary_function<const _T1*, _Res>
{ };
// - a pointer to member function type (binary, const)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const>
: binary_function<const _T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, volatile)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() volatile>
: unary_function<volatile _T1*, _Res>
{ };
// - a pointer to member function type (binary, volatile)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) volatile>
: binary_function<volatile _T1*, _T2, _Res>
{ };
// - a pointer to member function type (unary, const volatile)
template<typename _Res, typename _T1>
struct _Reference_wrapper_base<_Res (_T1::*)() const volatile>
: unary_function<const volatile _T1*, _Res>
{ };
// - a pointer to member function type (binary, const volatile)
template<typename _Res, typename _T1, typename _T2>
struct _Reference_wrapper_base<_Res (_T1::*)(_T2) const volatile>
: binary_function<const volatile _T1*, _T2, _Res>
{ };
/**
* @brief Primary class template for reference_wrapper.
* @ingroup functors
* @{
*/
template<typename _Tp>
class reference_wrapper
: public _Reference_wrapper_base<typename remove_cv<_Tp>::type>
{
_Tp* _M_data;
public:
typedef _Tp type;
reference_wrapper(_Tp& __indata) noexcept
: _M_data(std::__addressof(__indata))
{ }
reference_wrapper(_Tp&&) = delete;
reference_wrapper(const reference_wrapper&) = default;
reference_wrapper&
operator=(const reference_wrapper&) = default;
operator _Tp&() const noexcept
{ return this->get(); }
_Tp&
get() const noexcept
{ return *_M_data; }
template<typename... _Args>
typename result_of<_Tp&(_Args&&...)>::type
operator()(_Args&&... __args) const
{
return __invoke(get(), std::forward<_Args>(__args)...);
}
};
/// Denotes a reference should be taken to a variable.
template<typename _Tp>
inline reference_wrapper<_Tp>
ref(_Tp& __t) noexcept
{ return reference_wrapper<_Tp>(__t); }
/// Denotes a const reference should be taken to a variable.
template<typename _Tp>
inline reference_wrapper<const _Tp>
cref(const _Tp& __t) noexcept
{ return reference_wrapper<const _Tp>(__t); }
template<typename _Tp>
void ref(const _Tp&&) = delete;
template<typename _Tp>
void cref(const _Tp&&) = delete;
/// std::ref overload to prevent wrapping a reference_wrapper
template<typename _Tp>
inline reference_wrapper<_Tp>
ref(reference_wrapper<_Tp> __t) noexcept
{ return std::ref(__t.get()); }
/// std::cref overload to prevent wrapping a reference_wrapper
template<typename _Tp>
inline reference_wrapper<const _Tp>
cref(reference_wrapper<_Tp> __t) noexcept
{ return std::cref(__t.get()); }
// @} group functors
template<typename... _Types>
struct _Pack : integral_constant<size_t, sizeof...(_Types)>
{ };
template<typename _From, typename _To, bool = _From::value == _To::value>
struct _AllConvertible : false_type
{ };
template<typename... _From, typename... _To>
struct _AllConvertible<_Pack<_From...>, _Pack<_To...>, true>
: __and_<is_convertible<_From, _To>...>
{ };
template<typename _Tp1, typename _Tp2>
using _NotSame = __not_<is_same<typename std::decay<_Tp1>::type,
typename std::decay<_Tp2>::type>>;
/**
* Derives from @c unary_function or @c binary_function, or perhaps
* nothing, depending on the number of arguments provided. The
* primary template is the basis case, which derives nothing.
*/
template<typename _Res, typename... _ArgTypes>
struct _Maybe_unary_or_binary_function { };
/// Derives from @c unary_function, as appropriate.
template<typename _Res, typename _T1>
struct _Maybe_unary_or_binary_function<_Res, _T1>
: std::unary_function<_T1, _Res> { };
/// Derives from @c binary_function, as appropriate.
template<typename _Res, typename _T1, typename _T2>
struct _Maybe_unary_or_binary_function<_Res, _T1, _T2>
: std::binary_function<_T1, _T2, _Res> { };
template<typename _Signature>
struct _Mem_fn_traits;
template<typename _Res, typename _Class, typename... _ArgTypes>
struct _Mem_fn_traits_base
{
using __result_type = _Res;
using __class_type = _Class;
using __arg_types = _Pack<_ArgTypes...>;
using __maybe_type
= _Maybe_unary_or_binary_function<_Res, _Class*, _ArgTypes...>;
using __arity = integral_constant<size_t, sizeof...(_ArgTypes)>;
};
#define _GLIBCXX_MEM_FN_TRAITS2(_CV, _REF, _LVAL, _RVAL) \
template<typename _Res, typename _Class, typename... _ArgTypes> \
struct _Mem_fn_traits<_Res (_Class::*)(_ArgTypes...) _CV _REF> \
: _Mem_fn_traits_base<_Res, _CV _Class, _ArgTypes...> \
{ \
using __pmf_type = _Res (_Class::*)(_ArgTypes...) _CV _REF; \
using __lvalue = _LVAL; \
using __rvalue = _RVAL; \
using __vararg = false_type; \
}; \
template<typename _Res, typename _Class, typename... _ArgTypes> \
struct _Mem_fn_traits<_Res (_Class::*)(_ArgTypes... ...) _CV _REF> \
: _Mem_fn_traits_base<_Res, _CV _Class, _ArgTypes...> \
{ \
using __pmf_type = _Res (_Class::*)(_ArgTypes... ...) _CV _REF; \
using __lvalue = _LVAL; \
using __rvalue = _RVAL; \
using __vararg = true_type; \
};
#define _GLIBCXX_MEM_FN_TRAITS(_REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2( , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(const , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(volatile , _REF, _LVAL, _RVAL) \
_GLIBCXX_MEM_FN_TRAITS2(const volatile, _REF, _LVAL, _RVAL)
_GLIBCXX_MEM_FN_TRAITS( , true_type, true_type)
_GLIBCXX_MEM_FN_TRAITS(&, true_type, false_type)
_GLIBCXX_MEM_FN_TRAITS(&&, false_type, true_type)
#undef _GLIBCXX_MEM_FN_TRAITS
#undef _GLIBCXX_MEM_FN_TRAITS2
template<typename _MemFunPtr,
bool __is_mem_fn = is_member_function_pointer<_MemFunPtr>::value>
class _Mem_fn_base
: public _Mem_fn_traits<_MemFunPtr>::__maybe_type
{
using _Traits = _Mem_fn_traits<_MemFunPtr>;
using _Class = typename _Traits::__class_type;
using _ArgTypes = typename _Traits::__arg_types;
using _Pmf = typename _Traits::__pmf_type;
using _Arity = typename _Traits::__arity;
using _Varargs = typename _Traits::__vararg;
template<typename _Func, typename... _BoundArgs>
friend struct _Bind_check_arity;
// for varargs functions we just check the number of arguments,
// otherwise we also check they are convertible.
template<typename _Args>
using _CheckArgs = typename conditional<_Varargs::value,
__bool_constant<(_Args::value >= _ArgTypes::value)>,
_AllConvertible<_Args, _ArgTypes>
>::type;
public:
using result_type = typename _Traits::__result_type;
explicit _Mem_fn_base(_Pmf __pmf) : _M_pmf(__pmf) { }
// Handle objects
template<typename... _Args, typename _Req
= _Require<typename _Traits::__lvalue,
_CheckArgs<_Pack<_Args...>>>>
result_type
operator()(_Class& __object, _Args&&... __args) const
{ return (__object.*_M_pmf)(std::forward<_Args>(__args)...); }
template<typename... _Args, typename _Req
= _Require<typename _Traits::__rvalue,
_CheckArgs<_Pack<_Args...>>>>
result_type
operator()(_Class&& __object, _Args&&... __args) const
{
return (std::move(__object).*_M_pmf)(std::forward<_Args>(__args)...);
}
// Handle pointers
template<typename... _Args, typename _Req
= _Require<typename _Traits::__lvalue,
_CheckArgs<_Pack<_Args...>>>>
result_type
operator()(_Class* __object, _Args&&... __args) const
{ return (__object->*_M_pmf)(std::forward<_Args>(__args)...); }
// Handle smart pointers, references and pointers to derived
template<typename _Tp, typename... _Args, typename _Req
= _Require<_NotSame<_Class, _Tp>, _NotSame<_Class*, _Tp>,
_CheckArgs<_Pack<_Args...>>>>
result_type
operator()(_Tp&& __object, _Args&&... __args) const
{
return _M_call(std::forward<_Tp>(__object), &__object,
std::forward<_Args>(__args)...);
}
// Handle reference wrappers
template<typename _Tp, typename... _Args, typename _Req
= _Require<is_base_of<_Class, _Tp>, typename _Traits::__lvalue,
_CheckArgs<_Pack<_Args...>>>>
result_type
operator()(reference_wrapper<_Tp> __ref, _Args&&... __args) const
{ return operator()(__ref.get(), std::forward<_Args>(__args)...); }
private:
template<typename _Tp, typename... _Args>
result_type
_M_call(_Tp&& __object, const volatile _Class *,
_Args&&... __args) const
{
return (std::forward<_Tp>(__object).*_M_pmf)
(std::forward<_Args>(__args)...);
}
template<typename _Tp, typename... _Args>
result_type
_M_call(_Tp&& __ptr, const volatile void *, _Args&&... __args) const
{ return ((*__ptr).*_M_pmf)(std::forward<_Args>(__args)...); }
_Pmf _M_pmf;
};
// Partial specialization for member object pointers.
template<typename _Res, typename _Class>
class _Mem_fn_base<_Res _Class::*, false>
{
using __pm_type = _Res _Class::*;
// This bit of genius is due to Peter Dimov, improved slightly by
// Douglas Gregor.
// Made less elegant to support perfect forwarding and noexcept.
template<typename _Tp>
auto
_M_call(_Tp&& __object, const _Class *) const noexcept
-> decltype(std::forward<_Tp>(__object).*std::declval<__pm_type&>())
{ return std::forward<_Tp>(__object).*_M_pm; }
template<typename _Tp, typename _Up>
auto
_M_call(_Tp&& __object, _Up * const *) const noexcept
-> decltype((*std::forward<_Tp>(__object)).*std::declval<__pm_type&>())
{ return (*std::forward<_Tp>(__object)).*_M_pm; }
template<typename _Tp>
auto
_M_call(_Tp&& __ptr, const volatile void*) const
noexcept(noexcept((*__ptr).*std::declval<__pm_type&>()))
-> decltype((*__ptr).*std::declval<__pm_type&>())
{ return (*__ptr).*_M_pm; }
using _Arity = integral_constant<size_t, 0>;
using _Varargs = false_type;
template<typename _Func, typename... _BoundArgs>
friend struct _Bind_check_arity;
public:
explicit
_Mem_fn_base(_Res _Class::*__pm) noexcept : _M_pm(__pm) { }
// Handle objects
_Res&
operator()(_Class& __object) const noexcept
{ return __object.*_M_pm; }
const _Res&
operator()(const _Class& __object) const noexcept
{ return __object.*_M_pm; }
_Res&&
operator()(_Class&& __object) const noexcept
{ return std::forward<_Class>(__object).*_M_pm; }
const _Res&&
operator()(const _Class&& __object) const noexcept
{ return std::forward<const _Class>(__object).*_M_pm; }
// Handle pointers
_Res&
operator()(_Class* __object) const noexcept
{ return __object->*_M_pm; }
const _Res&
operator()(const _Class* __object) const noexcept
{ return __object->*_M_pm; }
// Handle smart pointers and derived
template<typename _Tp, typename _Req = _Require<_NotSame<_Class*, _Tp>>>
auto
operator()(_Tp&& __unknown) const
noexcept(noexcept(std::declval<_Mem_fn_base*>()->_M_call
(std::forward<_Tp>(__unknown), &__unknown)))
-> decltype(this->_M_call(std::forward<_Tp>(__unknown), &__unknown))
{ return _M_call(std::forward<_Tp>(__unknown), &__unknown); }
template<typename _Tp, typename _Req = _Require<is_base_of<_Class, _Tp>>>
auto
operator()(reference_wrapper<_Tp> __ref) const
noexcept(noexcept(std::declval<_Mem_fn_base&>()(__ref.get())))
-> decltype((*this)(__ref.get()))
{ return (*this)(__ref.get()); }
private:
_Res _Class::*_M_pm;
};
template<typename _Res, typename _Class>
struct _Mem_fn<_Res _Class::*>
: _Mem_fn_base<_Res _Class::*>
{
using _Mem_fn_base<_Res _Class::*>::_Mem_fn_base;
};
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2048. Unnecessary mem_fn overloads
/**
* @brief Returns a function object that forwards to the member
* pointer @a pm.
* @ingroup functors
*/
template<typename _Tp, typename _Class>
inline _Mem_fn<_Tp _Class::*>
mem_fn(_Tp _Class::* __pm) noexcept
{
return _Mem_fn<_Tp _Class::*>(__pm);
}
/**
* @brief Determines if the given type _Tp is a function object
* should be treated as a subexpression when evaluating calls to
* function objects returned by bind(). [TR1 3.6.1]
* @ingroup binders
*/
template<typename _Tp>
struct is_bind_expression
: public false_type { };
/**
* @brief Determines if the given type _Tp is a placeholder in a
* bind() expression and, if so, which placeholder it is. [TR1 3.6.2]
* @ingroup binders
*/
template<typename _Tp>
struct is_placeholder
: public integral_constant<int, 0>
{ };
/** @brief The type of placeholder objects defined by libstdc++.
* @ingroup binders
*/
template<int _Num> struct _Placeholder { };
_GLIBCXX_END_NAMESPACE_VERSION
/** @namespace std::placeholders
* @brief ISO C++11 entities sub-namespace for functional.
* @ingroup binders
*/
namespace placeholders
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/* Define a large number of placeholders. There is no way to
* simplify this with variadic templates, because we're introducing
* unique names for each.
*/
extern const _Placeholder<1> _1;
extern const _Placeholder<2> _2;
extern const _Placeholder<3> _3;
extern const _Placeholder<4> _4;
extern const _Placeholder<5> _5;
extern const _Placeholder<6> _6;
extern const _Placeholder<7> _7;
extern const _Placeholder<8> _8;
extern const _Placeholder<9> _9;
extern const _Placeholder<10> _10;
extern const _Placeholder<11> _11;
extern const _Placeholder<12> _12;
extern const _Placeholder<13> _13;
extern const _Placeholder<14> _14;
extern const _Placeholder<15> _15;
extern const _Placeholder<16> _16;
extern const _Placeholder<17> _17;
extern const _Placeholder<18> _18;
extern const _Placeholder<19> _19;
extern const _Placeholder<20> _20;
extern const _Placeholder<21> _21;
extern const _Placeholder<22> _22;
extern const _Placeholder<23> _23;
extern const _Placeholder<24> _24;
extern const _Placeholder<25> _25;
extern const _Placeholder<26> _26;
extern const _Placeholder<27> _27;
extern const _Placeholder<28> _28;
extern const _Placeholder<29> _29;
_GLIBCXX_END_NAMESPACE_VERSION
}
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* Partial specialization of is_placeholder that provides the placeholder
* number for the placeholder objects defined by libstdc++.
* @ingroup binders
*/
template<int _Num>
struct is_placeholder<_Placeholder<_Num> >
: public integral_constant<int, _Num>
{ };
template<int _Num>
struct is_placeholder<const _Placeholder<_Num> >
: public integral_constant<int, _Num>
{ };
/**
* Used by _Safe_tuple_element to indicate that there is no tuple
* element at this position.
*/
struct _No_tuple_element;
/**
* Implementation helper for _Safe_tuple_element. This primary
* template handles the case where it is safe to use @c
* tuple_element.
*/
template<std::size_t __i, typename _Tuple, bool _IsSafe>
struct _Safe_tuple_element_impl
: tuple_element<__i, _Tuple> { };
/**
* Implementation helper for _Safe_tuple_element. This partial
* specialization handles the case where it is not safe to use @c
* tuple_element. We just return @c _No_tuple_element.
*/
template<std::size_t __i, typename _Tuple>
struct _Safe_tuple_element_impl<__i, _Tuple, false>
{
typedef _No_tuple_element type;
};
/**
* Like tuple_element, but returns @c _No_tuple_element when
* tuple_element would return an error.
*/
template<std::size_t __i, typename _Tuple>
struct _Safe_tuple_element
: _Safe_tuple_element_impl<__i, _Tuple,
(__i < tuple_size<_Tuple>::value)>
{ };
/**
* Maps an argument to bind() into an actual argument to the bound
* function object [TR1 3.6.3/5]. Only the first parameter should
* be specified: the rest are used to determine among the various
* implementations. Note that, although this class is a function
* object, it isn't entirely normal because it takes only two
* parameters regardless of the number of parameters passed to the
* bind expression. The first parameter is the bound argument and
* the second parameter is a tuple containing references to the
* rest of the arguments.
*/
template<typename _Arg,
bool _IsBindExp = is_bind_expression<_Arg>::value,
bool _IsPlaceholder = (is_placeholder<_Arg>::value > 0)>
class _Mu;
/**
* If the argument is reference_wrapper<_Tp>, returns the
* underlying reference. [TR1 3.6.3/5 bullet 1]
*/
template<typename _Tp>
class _Mu<reference_wrapper<_Tp>, false, false>
{
public:
typedef _Tp& result_type;
/* Note: This won't actually work for const volatile
* reference_wrappers, because reference_wrapper::get() is const
* but not volatile-qualified. This might be a defect in the TR.
*/
template<typename _CVRef, typename _Tuple>
result_type
operator()(_CVRef& __arg, _Tuple&) const volatile
{ return __arg.get(); }
};
/**
* If the argument is a bind expression, we invoke the underlying
* function object with the same cv-qualifiers as we are given and
* pass along all of our arguments (unwrapped). [TR1 3.6.3/5 bullet 2]
*/
template<typename _Arg>
class _Mu<_Arg, true, false>
{
public:
template<typename _CVArg, typename... _Args>
auto
operator()(_CVArg& __arg,
tuple<_Args...>& __tuple) const volatile
-> decltype(__arg(declval<_Args>()...))
{
// Construct an index tuple and forward to __call
typedef typename _Build_index_tuple<sizeof...(_Args)>::__type
_Indexes;
return this->__call(__arg, __tuple, _Indexes());
}
private:
// Invokes the underlying function object __arg by unpacking all
// of the arguments in the tuple.
template<typename _CVArg, typename... _Args, std::size_t... _Indexes>
auto
__call(_CVArg& __arg, tuple<_Args...>& __tuple,
const _Index_tuple<_Indexes...>&) const volatile
-> decltype(__arg(declval<_Args>()...))
{
return __arg(std::forward<_Args>(std::get<_Indexes>(__tuple))...);
}
};
/**
* If the argument is a placeholder for the Nth argument, returns
* a reference to the Nth argument to the bind function object.
* [TR1 3.6.3/5 bullet 3]
*/
template<typename _Arg>
class _Mu<_Arg, false, true>
{
public:
template<typename _Signature> class result;
template<typename _CVMu, typename _CVArg, typename _Tuple>
class result<_CVMu(_CVArg, _Tuple)>
{
// Add a reference, if it hasn't already been done for us.
// This allows us to be a little bit sloppy in constructing
// the tuple that we pass to result_of<...>.
typedef typename _Safe_tuple_element<(is_placeholder<_Arg>::value
- 1), _Tuple>::type
__base_type;
public:
typedef typename add_rvalue_reference<__base_type>::type type;
};
template<typename _Tuple>
typename result<_Mu(_Arg, _Tuple)>::type
operator()(const volatile _Arg&, _Tuple& __tuple) const volatile
{
return std::forward<typename result<_Mu(_Arg, _Tuple)>::type>(
::std::get<(is_placeholder<_Arg>::value - 1)>(__tuple));
}
};
/**
* If the argument is just a value, returns a reference to that
* value. The cv-qualifiers on the reference are the same as the
* cv-qualifiers on the _Mu object. [TR1 3.6.3/5 bullet 4]
*/
template<typename _Arg>
class _Mu<_Arg, false, false>
{
public:
template<typename _Signature> struct result;
template<typename _CVMu, typename _CVArg, typename _Tuple>
struct result<_CVMu(_CVArg, _Tuple)>
{
typedef typename add_lvalue_reference<_CVArg>::type type;
};
// Pick up the cv-qualifiers of the argument
template<typename _CVArg, typename _Tuple>
_CVArg&&
operator()(_CVArg&& __arg, _Tuple&) const volatile
{ return std::forward<_CVArg>(__arg); }
};
/**
* Maps member pointers into instances of _Mem_fn but leaves all
* other function objects untouched. Used by std::bind(). The
* primary template handles the non-member-pointer case.
*/
template<typename _Tp>
struct _Maybe_wrap_member_pointer
{
typedef _Tp type;
static const _Tp&
__do_wrap(const _Tp& __x)
{ return __x; }
static _Tp&&
__do_wrap(_Tp&& __x)
{ return static_cast<_Tp&&>(__x); }
};
/**
* Maps member pointers into instances of _Mem_fn but leaves all
* other function objects untouched. Used by std::bind(). This
* partial specialization handles the member pointer case.
*/
template<typename _Tp, typename _Class>
struct _Maybe_wrap_member_pointer<_Tp _Class::*>
{
typedef _Mem_fn<_Tp _Class::*> type;
static type
__do_wrap(_Tp _Class::* __pm)
{ return type(__pm); }
};
// Specialization needed to prevent "forming reference to void" errors when
// bind<void>() is called, because argument deduction instantiates
// _Maybe_wrap_member_pointer<void> outside the immediate context where
// SFINAE applies.
template<>
struct _Maybe_wrap_member_pointer<void>
{
typedef void type;
};
// std::get<I> for volatile-qualified tuples
template<std::size_t _Ind, typename... _Tp>
inline auto
__volget(volatile tuple<_Tp...>& __tuple)
-> __tuple_element_t<_Ind, tuple<_Tp...>> volatile&
{ return std::get<_Ind>(const_cast<tuple<_Tp...>&>(__tuple)); }
// std::get<I> for const-volatile-qualified tuples
template<std::size_t _Ind, typename... _Tp>
inline auto
__volget(const volatile tuple<_Tp...>& __tuple)
-> __tuple_element_t<_Ind, tuple<_Tp...>> const volatile&
{ return std::get<_Ind>(const_cast<const tuple<_Tp...>&>(__tuple)); }
/// Type of the function object returned from bind().
template<typename _Signature>
struct _Bind;
template<typename _Functor, typename... _Bound_args>
class _Bind<_Functor(_Bound_args...)>
: public _Weak_result_type<_Functor>
{
typedef _Bind __self_type;
typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
_Bound_indexes;
_Functor _M_f;
tuple<_Bound_args...> _M_bound_args;
// Call unqualified
template<typename _Result, typename... _Args, std::size_t... _Indexes>
_Result
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>)
{
return _M_f(_Mu<_Bound_args>()
(std::get<_Indexes>(_M_bound_args), __args)...);
}
// Call as const
template<typename _Result, typename... _Args, std::size_t... _Indexes>
_Result
__call_c(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>) const
{
return _M_f(_Mu<_Bound_args>()
(std::get<_Indexes>(_M_bound_args), __args)...);
}
// Call as volatile
template<typename _Result, typename... _Args, std::size_t... _Indexes>
_Result
__call_v(tuple<_Args...>&& __args,
_Index_tuple<_Indexes...>) volatile
{
return _M_f(_Mu<_Bound_args>()
(__volget<_Indexes>(_M_bound_args), __args)...);
}
// Call as const volatile
template<typename _Result, typename... _Args, std::size_t... _Indexes>
_Result
__call_c_v(tuple<_Args...>&& __args,
_Index_tuple<_Indexes...>) const volatile
{
return _M_f(_Mu<_Bound_args>()
(__volget<_Indexes>(_M_bound_args), __args)...);
}
public:
template<typename... _Args>
explicit _Bind(const _Functor& __f, _Args&&... __args)
: _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
{ }
template<typename... _Args>
explicit _Bind(_Functor&& __f, _Args&&... __args)
: _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
{ }
_Bind(const _Bind&) = default;
_Bind(_Bind&& __b)
: _M_f(std::move(__b._M_f)), _M_bound_args(std::move(__b._M_bound_args))
{ }
// Call unqualified
template<typename... _Args, typename _Result
= decltype( std::declval<_Functor&>()(
_Mu<_Bound_args>()( std::declval<_Bound_args&>(),
std::declval<tuple<_Args...>&>() )... ) )>
_Result
operator()(_Args&&... __args)
{
return this->__call<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
// Call as const
template<typename... _Args, typename _Result
= decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
typename add_const<_Functor>::type&>::type>()(
_Mu<_Bound_args>()( std::declval<const _Bound_args&>(),
std::declval<tuple<_Args...>&>() )... ) )>
_Result
operator()(_Args&&... __args) const
{
return this->__call_c<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
// Call as volatile
template<typename... _Args, typename _Result
= decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
typename add_volatile<_Functor>::type&>::type>()(
_Mu<_Bound_args>()( std::declval<volatile _Bound_args&>(),
std::declval<tuple<_Args...>&>() )... ) )>
_Result
operator()(_Args&&... __args) volatile
{
return this->__call_v<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
// Call as const volatile
template<typename... _Args, typename _Result
= decltype( std::declval<typename enable_if<(sizeof...(_Args) >= 0),
typename add_cv<_Functor>::type&>::type>()(
_Mu<_Bound_args>()( std::declval<const volatile _Bound_args&>(),
std::declval<tuple<_Args...>&>() )... ) )>
_Result
operator()(_Args&&... __args) const volatile
{
return this->__call_c_v<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
};
/// Type of the function object returned from bind<R>().
template<typename _Result, typename _Signature>
struct _Bind_result;
template<typename _Result, typename _Functor, typename... _Bound_args>
class _Bind_result<_Result, _Functor(_Bound_args...)>
{
typedef _Bind_result __self_type;
typedef typename _Build_index_tuple<sizeof...(_Bound_args)>::__type
_Bound_indexes;
_Functor _M_f;
tuple<_Bound_args...> _M_bound_args;
// sfinae types
template<typename _Res>
struct __enable_if_void : enable_if<is_void<_Res>::value, int> { };
template<typename _Res>
struct __disable_if_void : enable_if<!is_void<_Res>::value, int> { };
// Call unqualified
template<typename _Res, typename... _Args, std::size_t... _Indexes>
_Result
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
typename __disable_if_void<_Res>::type = 0)
{
return _M_f(_Mu<_Bound_args>()
(std::get<_Indexes>(_M_bound_args), __args)...);
}
// Call unqualified, return void
template<typename _Res, typename... _Args, std::size_t... _Indexes>
void
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
typename __enable_if_void<_Res>::type = 0)
{
_M_f(_Mu<_Bound_args>()
(std::get<_Indexes>(_M_bound_args), __args)...);
}
// Call as const
template<typename _Res, typename... _Args, std::size_t... _Indexes>
_Result
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
typename __disable_if_void<_Res>::type = 0) const
{
return _M_f(_Mu<_Bound_args>()
(std::get<_Indexes>(_M_bound_args), __args)...);
}
// Call as const, return void
template<typename _Res, typename... _Args, std::size_t... _Indexes>
void
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
typename __enable_if_void<_Res>::type = 0) const
{
_M_f(_Mu<_Bound_args>()
(std::get<_Indexes>(_M_bound_args), __args)...);
}
// Call as volatile
template<typename _Res, typename... _Args, std::size_t... _Indexes>
_Result
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
typename __disable_if_void<_Res>::type = 0) volatile
{
return _M_f(_Mu<_Bound_args>()
(__volget<_Indexes>(_M_bound_args), __args)...);
}
// Call as volatile, return void
template<typename _Res, typename... _Args, std::size_t... _Indexes>
void
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
typename __enable_if_void<_Res>::type = 0) volatile
{
_M_f(_Mu<_Bound_args>()
(__volget<_Indexes>(_M_bound_args), __args)...);
}
// Call as const volatile
template<typename _Res, typename... _Args, std::size_t... _Indexes>
_Result
__call(tuple<_Args...>&& __args, _Index_tuple<_Indexes...>,
typename __disable_if_void<_Res>::type = 0) const volatile
{
return _M_f(_Mu<_Bound_args>()
(__volget<_Indexes>(_M_bound_args), __args)...);
}
// Call as const volatile, return void
template<typename _Res, typename... _Args, std::size_t... _Indexes>
void
__call(tuple<_Args...>&& __args,
_Index_tuple<_Indexes...>,
typename __enable_if_void<_Res>::type = 0) const volatile
{
_M_f(_Mu<_Bound_args>()
(__volget<_Indexes>(_M_bound_args), __args)...);
}
public:
typedef _Result result_type;
template<typename... _Args>
explicit _Bind_result(const _Functor& __f, _Args&&... __args)
: _M_f(__f), _M_bound_args(std::forward<_Args>(__args)...)
{ }
template<typename... _Args>
explicit _Bind_result(_Functor&& __f, _Args&&... __args)
: _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
{ }
_Bind_result(const _Bind_result&) = default;
_Bind_result(_Bind_result&& __b)
: _M_f(std::move(__b._M_f)), _M_bound_args(std::move(__b._M_bound_args))
{ }
// Call unqualified
template<typename... _Args>
result_type
operator()(_Args&&... __args)
{
return this->__call<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
// Call as const
template<typename... _Args>
result_type
operator()(_Args&&... __args) const
{
return this->__call<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
// Call as volatile
template<typename... _Args>
result_type
operator()(_Args&&... __args) volatile
{
return this->__call<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
// Call as const volatile
template<typename... _Args>
result_type
operator()(_Args&&... __args) const volatile
{
return this->__call<_Result>(
std::forward_as_tuple(std::forward<_Args>(__args)...),
_Bound_indexes());
}
};
/**
* @brief Class template _Bind is always a bind expression.
* @ingroup binders
*/
template<typename _Signature>
struct is_bind_expression<_Bind<_Signature> >
: public true_type { };
/**
* @brief Class template _Bind is always a bind expression.
* @ingroup binders
*/
template<typename _Signature>
struct is_bind_expression<const _Bind<_Signature> >
: public true_type { };
/**
* @brief Class template _Bind is always a bind expression.
* @ingroup binders
*/
template<typename _Signature>
struct is_bind_expression<volatile _Bind<_Signature> >
: public true_type { };
/**
* @brief Class template _Bind is always a bind expression.
* @ingroup binders
*/
template<typename _Signature>
struct is_bind_expression<const volatile _Bind<_Signature>>
: public true_type { };
/**
* @brief Class template _Bind_result is always a bind expression.
* @ingroup binders
*/
template<typename _Result, typename _Signature>
struct is_bind_expression<_Bind_result<_Result, _Signature>>
: public true_type { };
/**
* @brief Class template _Bind_result is always a bind expression.
* @ingroup binders
*/
template<typename _Result, typename _Signature>
struct is_bind_expression<const _Bind_result<_Result, _Signature>>
: public true_type { };
/**
* @brief Class template _Bind_result is always a bind expression.
* @ingroup binders
*/
template<typename _Result, typename _Signature>
struct is_bind_expression<volatile _Bind_result<_Result, _Signature>>
: public true_type { };
/**
* @brief Class template _Bind_result is always a bind expression.
* @ingroup binders
*/
template<typename _Result, typename _Signature>
struct is_bind_expression<const volatile _Bind_result<_Result, _Signature>>
: public true_type { };
template<typename _Func, typename... _BoundArgs>
struct _Bind_check_arity { };
template<typename _Ret, typename... _Args, typename... _BoundArgs>
struct _Bind_check_arity<_Ret (*)(_Args...), _BoundArgs...>
{
static_assert(sizeof...(_BoundArgs) == sizeof...(_Args),
"Wrong number of arguments for function");
};
template<typename _Ret, typename... _Args, typename... _BoundArgs>
struct _Bind_check_arity<_Ret (*)(_Args......), _BoundArgs...>
{
static_assert(sizeof...(_BoundArgs) >= sizeof...(_Args),
"Wrong number of arguments for function");
};
template<typename _Tp, typename _Class, typename... _BoundArgs>
struct _Bind_check_arity<_Tp _Class::*, _BoundArgs...>
{
using _Arity = typename _Mem_fn<_Tp _Class::*>::_Arity;
using _Varargs = typename _Mem_fn<_Tp _Class::*>::_Varargs;
static_assert(_Varargs::value
? sizeof...(_BoundArgs) >= _Arity::value + 1
: sizeof...(_BoundArgs) == _Arity::value + 1,
"Wrong number of arguments for pointer-to-member");
};
// Trait type used to remove std::bind() from overload set via SFINAE
// when first argument has integer type, so that std::bind() will
// not be a better match than ::bind() from the BSD Sockets API.
template<typename _Tp, typename _Tp2 = typename decay<_Tp>::type>
using __is_socketlike = __or_<is_integral<_Tp2>, is_enum<_Tp2>>;
template<bool _SocketLike, typename _Func, typename... _BoundArgs>
struct _Bind_helper
: _Bind_check_arity<typename decay<_Func>::type, _BoundArgs...>
{
typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
__maybe_type;
typedef typename __maybe_type::type __func_type;
typedef _Bind<__func_type(typename decay<_BoundArgs>::type...)> type;
};
// Partial specialization for is_socketlike == true, does not define
// nested type so std::bind() will not participate in overload resolution
// when the first argument might be a socket file descriptor.
template<typename _Func, typename... _BoundArgs>
struct _Bind_helper<true, _Func, _BoundArgs...>
{ };
/**
* @brief Function template for std::bind.
* @ingroup binders
*/
template<typename _Func, typename... _BoundArgs>
inline typename
_Bind_helper<__is_socketlike<_Func>::value, _Func, _BoundArgs...>::type
bind(_Func&& __f, _BoundArgs&&... __args)
{
typedef _Bind_helper<false, _Func, _BoundArgs...> __helper_type;
typedef typename __helper_type::__maybe_type __maybe_type;
typedef typename __helper_type::type __result_type;
return __result_type(__maybe_type::__do_wrap(std::forward<_Func>(__f)),
std::forward<_BoundArgs>(__args)...);
}
template<typename _Result, typename _Func, typename... _BoundArgs>
struct _Bindres_helper
: _Bind_check_arity<typename decay<_Func>::type, _BoundArgs...>
{
typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
__maybe_type;
typedef typename __maybe_type::type __functor_type;
typedef _Bind_result<_Result,
__functor_type(typename decay<_BoundArgs>::type...)>
type;
};
/**
* @brief Function template for std::bind<R>.
* @ingroup binders
*/
template<typename _Result, typename _Func, typename... _BoundArgs>
inline
typename _Bindres_helper<_Result, _Func, _BoundArgs...>::type
bind(_Func&& __f, _BoundArgs&&... __args)
{
typedef _Bindres_helper<_Result, _Func, _BoundArgs...> __helper_type;
typedef typename __helper_type::__maybe_type __maybe_type;
typedef typename __helper_type::type __result_type;
return __result_type(__maybe_type::__do_wrap(std::forward<_Func>(__f)),
std::forward<_BoundArgs>(__args)...);
}
template<typename _Signature>
struct _Bind_simple;
template<typename _Callable, typename... _Args>
struct _Bind_simple<_Callable(_Args...)>
{
typedef typename result_of<_Callable(_Args...)>::type result_type;
template<typename _Tp, typename... _Up>
explicit
_Bind_simple(_Tp&& __f, _Up&&... __args)
: _M_bound(std::forward<_Tp>(__f), std::forward<_Up>(__args)...)
{ }
_Bind_simple(const _Bind_simple&) = default;
_Bind_simple(_Bind_simple&&) = default;
result_type
operator()()
{
typedef typename _Build_index_tuple<sizeof...(_Args)>::__type _Indices;
return _M_invoke(_Indices());
}
private:
template<std::size_t... _Indices>
typename result_of<_Callable(_Args...)>::type
_M_invoke(_Index_tuple<_Indices...>)
{
// std::bind always forwards bound arguments as lvalues,
// but this type can call functions which only accept rvalues.
return std::forward<_Callable>(std::get<0>(_M_bound))(
std::forward<_Args>(std::get<_Indices+1>(_M_bound))...);
}
std::tuple<_Callable, _Args...> _M_bound;
};
template<typename _Func, typename... _BoundArgs>
struct _Bind_simple_helper
: _Bind_check_arity<typename decay<_Func>::type, _BoundArgs...>
{
typedef _Maybe_wrap_member_pointer<typename decay<_Func>::type>
__maybe_type;
typedef typename __maybe_type::type __func_type;
typedef _Bind_simple<__func_type(typename decay<_BoundArgs>::type...)>
__type;
};
// Simplified version of std::bind for internal use, without support for
// unbound arguments, placeholders or nested bind expressions.
template<typename _Callable, typename... _Args>
typename _Bind_simple_helper<_Callable, _Args...>::__type
__bind_simple(_Callable&& __callable, _Args&&... __args)
{
typedef _Bind_simple_helper<_Callable, _Args...> __helper_type;
typedef typename __helper_type::__maybe_type __maybe_type;
typedef typename __helper_type::__type __result_type;
return __result_type(
__maybe_type::__do_wrap( std::forward<_Callable>(__callable)),
std::forward<_Args>(__args)...);
}
/**
* @brief Exception class thrown when class template function's
* operator() is called with an empty target.
* @ingroup exceptions
*/
class bad_function_call : public std::exception
{
public:
virtual ~bad_function_call() noexcept;
const char* what() const noexcept;
};
/**
* Trait identifying "location-invariant" types, meaning that the
* address of the object (or any of its members) will not escape.
* Trivially copyable types are location-invariant and users can
* specialize this trait for other types.
*/
template<typename _Tp>
struct __is_location_invariant
: is_trivially_copyable<_Tp>::type
{ };
class _Undefined_class;
union _Nocopy_types
{
void* _M_object;
const void* _M_const_object;
void (*_M_function_pointer)();
void (_Undefined_class::*_M_member_pointer)();
};
union [[gnu::may_alias]] _Any_data
{
void* _M_access() { return &_M_pod_data[0]; }
const void* _M_access() const { return &_M_pod_data[0]; }
template<typename _Tp>
_Tp&
_M_access()
{ return *static_cast<_Tp*>(_M_access()); }
template<typename _Tp>
const _Tp&
_M_access() const
{ return *static_cast<const _Tp*>(_M_access()); }
_Nocopy_types _M_unused;
char _M_pod_data[sizeof(_Nocopy_types)];
};
enum _Manager_operation
{
__get_type_info,
__get_functor_ptr,
__clone_functor,
__destroy_functor
};
// Simple type wrapper that helps avoid annoying const problems
// when casting between void pointers and pointers-to-pointers.
template<typename _Tp>
struct _Simple_type_wrapper
{
_Simple_type_wrapper(_Tp __value) : __value(__value) { }
_Tp __value;
};
template<typename _Tp>
struct __is_location_invariant<_Simple_type_wrapper<_Tp> >
: __is_location_invariant<_Tp>
{ };
// Converts a reference to a function object into a callable
// function object.
template<typename _Functor>
inline _Functor&
__callable_functor(_Functor& __f)
{ return __f; }
template<typename _Member, typename _Class>
inline _Mem_fn<_Member _Class::*>
__callable_functor(_Member _Class::* &__p)
{ return std::mem_fn(__p); }
template<typename _Member, typename _Class>
inline _Mem_fn<_Member _Class::*>
__callable_functor(_Member _Class::* const &__p)
{ return std::mem_fn(__p); }
template<typename _Member, typename _Class>
inline _Mem_fn<_Member _Class::*>
__callable_functor(_Member _Class::* volatile &__p)
{ return std::mem_fn(__p); }
template<typename _Member, typename _Class>
inline _Mem_fn<_Member _Class::*>
__callable_functor(_Member _Class::* const volatile &__p)
{ return std::mem_fn(__p); }
template<typename _Signature>
class function;
/// Base class of all polymorphic function object wrappers.
class _Function_base
{
public:
static const std::size_t _M_max_size = sizeof(_Nocopy_types);
static const std::size_t _M_max_align = __alignof__(_Nocopy_types);
template<typename _Functor>
class _Base_manager
{
protected:
static const bool __stored_locally =
(__is_location_invariant<_Functor>::value
&& sizeof(_Functor) <= _M_max_size
&& __alignof__(_Functor) <= _M_max_align
&& (_M_max_align % __alignof__(_Functor) == 0));
typedef integral_constant<bool, __stored_locally> _Local_storage;
// Retrieve a pointer to the function object
static _Functor*
_M_get_pointer(const _Any_data& __source)
{
const _Functor* __ptr =
__stored_locally? std::__addressof(__source._M_access<_Functor>())
/* have stored a pointer */ : __source._M_access<_Functor*>();
return const_cast<_Functor*>(__ptr);
}
// Clone a location-invariant function object that fits within
// an _Any_data structure.
static void
_M_clone(_Any_data& __dest, const _Any_data& __source, true_type)
{
::new (__dest._M_access()) _Functor(__source._M_access<_Functor>());
}
// Clone a function object that is not location-invariant or
// that cannot fit into an _Any_data structure.
static void
_M_clone(_Any_data& __dest, const _Any_data& __source, false_type)
{
__dest._M_access<_Functor*>() =
new _Functor(*__source._M_access<_Functor*>());
}
// Destroying a location-invariant object may still require
// destruction.
static void
_M_destroy(_Any_data& __victim, true_type)
{
__victim._M_access<_Functor>().~_Functor();
}
// Destroying an object located on the heap.
static void
_M_destroy(_Any_data& __victim, false_type)
{
delete __victim._M_access<_Functor*>();
}
public:
static bool
_M_manager(_Any_data& __dest, const _Any_data& __source,
_Manager_operation __op)
{
switch (__op)
{
#if __cpp_rtti
case __get_type_info:
__dest._M_access<const type_info*>() = &typeid(_Functor);
break;
#endif
case __get_functor_ptr:
__dest._M_access<_Functor*>() = _M_get_pointer(__source);
break;
case __clone_functor:
_M_clone(__dest, __source, _Local_storage());
break;
case __destroy_functor:
_M_destroy(__dest, _Local_storage());
break;
}
return false;
}
static void
_M_init_functor(_Any_data& __functor, _Functor&& __f)
{ _M_init_functor(__functor, std::move(__f), _Local_storage()); }
template<typename _Signature>
static bool
_M_not_empty_function(const function<_Signature>& __f)
{ return static_cast<bool>(__f); }
template<typename _Tp>
static bool
_M_not_empty_function(_Tp* __fp)
{ return __fp != nullptr; }
template<typename _Class, typename _Tp>
static bool
_M_not_empty_function(_Tp _Class::* __mp)
{ return __mp != nullptr; }
template<typename _Tp>
static bool
_M_not_empty_function(const _Tp&)
{ return true; }
private:
static void
_M_init_functor(_Any_data& __functor, _Functor&& __f, true_type)
{ ::new (__functor._M_access()) _Functor(std::move(__f)); }
static void
_M_init_functor(_Any_data& __functor, _Functor&& __f, false_type)
{ __functor._M_access<_Functor*>() = new _Functor(std::move(__f)); }
};
template<typename _Functor>
class _Ref_manager : public _Base_manager<_Functor*>
{
typedef _Function_base::_Base_manager<_Functor*> _Base;
public:
static bool
_M_manager(_Any_data& __dest, const _Any_data& __source,
_Manager_operation __op)
{
switch (__op)
{
#if __cpp_rtti
case __get_type_info:
__dest._M_access<const type_info*>() = &typeid(_Functor);
break;
#endif
case __get_functor_ptr:
__dest._M_access<_Functor*>() = *_Base::_M_get_pointer(__source);
return is_const<_Functor>::value;
break;
default:
_Base::_M_manager(__dest, __source, __op);
}
return false;
}
static void
_M_init_functor(_Any_data& __functor, reference_wrapper<_Functor> __f)
{
_Base::_M_init_functor(__functor, std::__addressof(__f.get()));
}
};
_Function_base() : _M_manager(nullptr) { }
~_Function_base()
{
if (_M_manager)
_M_manager(_M_functor, _M_functor, __destroy_functor);
}
bool _M_empty() const { return !_M_manager; }
typedef bool (*_Manager_type)(_Any_data&, const _Any_data&,
_Manager_operation);
_Any_data _M_functor;
_Manager_type _M_manager;
};
template<typename _Signature, typename _Functor>
class _Function_handler;
template<typename _Res, typename _Functor, typename... _ArgTypes>
class _Function_handler<_Res(_ArgTypes...), _Functor>
: public _Function_base::_Base_manager<_Functor>
{
typedef _Function_base::_Base_manager<_Functor> _Base;
public:
static _Res
_M_invoke(const _Any_data& __functor, _ArgTypes&&... __args)
{
return (*_Base::_M_get_pointer(__functor))(
std::forward<_ArgTypes>(__args)...);
}
};
template<typename _Functor, typename... _ArgTypes>
class _Function_handler<void(_ArgTypes...), _Functor>
: public _Function_base::_Base_manager<_Functor>
{
typedef _Function_base::_Base_manager<_Functor> _Base;
public:
static void
_M_invoke(const _Any_data& __functor, _ArgTypes&&... __args)
{
(*_Base::_M_get_pointer(__functor))(
std::forward<_ArgTypes>(__args)...);
}
};
template<typename _Res, typename _Functor, typename... _ArgTypes>
class _Function_handler<_Res(_ArgTypes...), reference_wrapper<_Functor> >
: public _Function_base::_Ref_manager<_Functor>
{
typedef _Function_base::_Ref_manager<_Functor> _Base;
public:
static _Res
_M_invoke(const _Any_data& __functor, _ArgTypes&&... __args)
{
return std::__callable_functor(**_Base::_M_get_pointer(__functor))(
std::forward<_ArgTypes>(__args)...);
}
};
template<typename _Functor, typename... _ArgTypes>
class _Function_handler<void(_ArgTypes...), reference_wrapper<_Functor> >
: public _Function_base::_Ref_manager<_Functor>
{
typedef _Function_base::_Ref_manager<_Functor> _Base;
public:
static void
_M_invoke(const _Any_data& __functor, _ArgTypes&&... __args)
{
std::__callable_functor(**_Base::_M_get_pointer(__functor))(
std::forward<_ArgTypes>(__args)...);
}
};
template<typename _Class, typename _Member, typename _Res,
typename... _ArgTypes>
class _Function_handler<_Res(_ArgTypes...), _Member _Class::*>
: public _Function_handler<void(_ArgTypes...), _Member _Class::*>
{
typedef _Function_handler<void(_ArgTypes...), _Member _Class::*>
_Base;
public:
static _Res
_M_invoke(const _Any_data& __functor, _ArgTypes&&... __args)
{
return std::mem_fn(_Base::_M_get_pointer(__functor)->__value)(
std::forward<_ArgTypes>(__args)...);
}
};
template<typename _Class, typename _Member, typename... _ArgTypes>
class _Function_handler<void(_ArgTypes...), _Member _Class::*>
: public _Function_base::_Base_manager<
_Simple_type_wrapper< _Member _Class::* > >
{
typedef _Member _Class::* _Functor;
typedef _Simple_type_wrapper<_Functor> _Wrapper;
typedef _Function_base::_Base_manager<_Wrapper> _Base;
public:
static bool
_M_manager(_Any_data& __dest, const _Any_data& __source,
_Manager_operation __op)
{
switch (__op)
{
#if __cpp_rtti
case __get_type_info:
__dest._M_access<const type_info*>() = &typeid(_Functor);
break;
#endif
case __get_functor_ptr:
__dest._M_access<_Functor*>() =
&_Base::_M_get_pointer(__source)->__value;
break;
default:
_Base::_M_manager(__dest, __source, __op);
}
return false;
}
static void
_M_invoke(const _Any_data& __functor, _ArgTypes&&... __args)
{
std::mem_fn(_Base::_M_get_pointer(__functor)->__value)(
std::forward<_ArgTypes>(__args)...);
}
};
template<typename _From, typename _To>
using __check_func_return_type
= __or_<is_void<_To>, is_convertible<_From, _To>>;
/**
* @brief Primary class template for std::function.
* @ingroup functors
*
* Polymorphic function wrapper.
*/
template<typename _Res, typename... _ArgTypes>
class function<_Res(_ArgTypes...)>
: public _Maybe_unary_or_binary_function<_Res, _ArgTypes...>,
private _Function_base
{
typedef _Res _Signature_type(_ArgTypes...);
template<typename _Func,
typename _Res2 = typename result_of<_Func&(_ArgTypes...)>::type>
struct _Callable : __check_func_return_type<_Res2, _Res> { };
// Used so the return type convertibility checks aren't done when
// performing overload resolution for copy construction/assignment.
template<typename _Tp>
struct _Callable<function, _Tp> : false_type { };
template<typename _Cond, typename _Tp>
using _Requires = typename enable_if<_Cond::value, _Tp>::type;
public:
typedef _Res result_type;
// [3.7.2.1] construct/copy/destroy
/**
* @brief Default construct creates an empty function call wrapper.
* @post @c !(bool)*this
*/
function() noexcept
: _Function_base() { }
/**
* @brief Creates an empty function call wrapper.
* @post @c !(bool)*this
*/
function(nullptr_t) noexcept
: _Function_base() { }
/**
* @brief %Function copy constructor.
* @param __x A %function object with identical call signature.
* @post @c bool(*this) == bool(__x)
*
* The newly-created %function contains a copy of the target of @a
* __x (if it has one).
*/
function(const function& __x);
/**
* @brief %Function move constructor.
* @param __x A %function object rvalue with identical call signature.
*
* The newly-created %function contains the target of @a __x
* (if it has one).
*/
function(function&& __x) noexcept : _Function_base()
{
__x.swap(*this);
}
// TODO: needs allocator_arg_t
/**
* @brief Builds a %function that targets a copy of the incoming
* function object.
* @param __f A %function object that is callable with parameters of
* type @c T1, @c T2, ..., @c TN and returns a value convertible
* to @c Res.
*
* The newly-created %function object will target a copy of
* @a __f. If @a __f is @c reference_wrapper<F>, then this function
* object will contain a reference to the function object @c
* __f.get(). If @a __f is a NULL function pointer or NULL
* pointer-to-member, the newly-created object will be empty.
*
* If @a __f is a non-NULL function pointer or an object of type @c
* reference_wrapper<F>, this function will not throw.
*/
template<typename _Functor,
typename = _Requires<__not_<is_same<_Functor, function>>, void>,
typename = _Requires<_Callable<_Functor>, void>>
function(_Functor);
/**
* @brief %Function assignment operator.
* @param __x A %function with identical call signature.
* @post @c (bool)*this == (bool)x
* @returns @c *this
*
* The target of @a __x is copied to @c *this. If @a __x has no
* target, then @c *this will be empty.
*
* If @a __x targets a function pointer or a reference to a function
* object, then this operation will not throw an %exception.
*/
function&
operator=(const function& __x)
{
function(__x).swap(*this);
return *this;
}
/**
* @brief %Function move-assignment operator.
* @param __x A %function rvalue with identical call signature.
* @returns @c *this
*
* The target of @a __x is moved to @c *this. If @a __x has no
* target, then @c *this will be empty.
*
* If @a __x targets a function pointer or a reference to a function
* object, then this operation will not throw an %exception.
*/
function&
operator=(function&& __x) noexcept
{
function(std::move(__x)).swap(*this);
return *this;
}
/**
* @brief %Function assignment to zero.
* @post @c !(bool)*this
* @returns @c *this
*
* The target of @c *this is deallocated, leaving it empty.
*/
function&
operator=(nullptr_t) noexcept
{
if (_M_manager)
{
_M_manager(_M_functor, _M_functor, __destroy_functor);
_M_manager = nullptr;
_M_invoker = nullptr;
}
return *this;
}
/**
* @brief %Function assignment to a new target.
* @param __f A %function object that is callable with parameters of
* type @c T1, @c T2, ..., @c TN and returns a value convertible
* to @c Res.
* @return @c *this
*
* This %function object wrapper will target a copy of @a
* __f. If @a __f is @c reference_wrapper<F>, then this function
* object will contain a reference to the function object @c
* __f.get(). If @a __f is a NULL function pointer or NULL
* pointer-to-member, @c this object will be empty.
*
* If @a __f is a non-NULL function pointer or an object of type @c
* reference_wrapper<F>, this function will not throw.
*/
template<typename _Functor>
_Requires<_Callable<typename decay<_Functor>::type>, function&>
operator=(_Functor&& __f)
{
function(std::forward<_Functor>(__f)).swap(*this);
return *this;
}
/// @overload
template<typename _Functor>
function&
operator=(reference_wrapper<_Functor> __f) noexcept
{
function(__f).swap(*this);
return *this;
}
// [3.7.2.2] function modifiers
/**
* @brief Swap the targets of two %function objects.
* @param __x A %function with identical call signature.
*
* Swap the targets of @c this function object and @a __f. This
* function will not throw an %exception.
*/
void swap(function& __x) noexcept
{
std::swap(_M_functor, __x._M_functor);
std::swap(_M_manager, __x._M_manager);
std::swap(_M_invoker, __x._M_invoker);
}
// TODO: needs allocator_arg_t
/*
template<typename _Functor, typename _Alloc>
void
assign(_Functor&& __f, const _Alloc& __a)
{
function(allocator_arg, __a,
std::forward<_Functor>(__f)).swap(*this);
}
*/
// [3.7.2.3] function capacity
/**
* @brief Determine if the %function wrapper has a target.
*
* @return @c true when this %function object contains a target,
* or @c false when it is empty.
*
* This function will not throw an %exception.
*/
explicit operator bool() const noexcept
{ return !_M_empty(); }
// [3.7.2.4] function invocation
/**
* @brief Invokes the function targeted by @c *this.
* @returns the result of the target.
* @throws bad_function_call when @c !(bool)*this
*
* The function call operator invokes the target function object
* stored by @c this.
*/
_Res operator()(_ArgTypes... __args) const;
#if __cpp_rtti
// [3.7.2.5] function target access
/**
* @brief Determine the type of the target of this function object
* wrapper.
*
* @returns the type identifier of the target function object, or
* @c typeid(void) if @c !(bool)*this.
*
* This function will not throw an %exception.
*/
const type_info& target_type() const noexcept;
/**
* @brief Access the stored target function object.
*
* @return Returns a pointer to the stored target function object,
* if @c typeid(Functor).equals(target_type()); otherwise, a NULL
* pointer.
*
* This function will not throw an %exception.
*/
template<typename _Functor> _Functor* target() noexcept;
/// @overload
template<typename _Functor> const _Functor* target() const noexcept;
#endif
private:
using _Invoker_type = _Res (*)(const _Any_data&, _ArgTypes&&...);
_Invoker_type _M_invoker;
};
// Out-of-line member definitions.
template<typename _Res, typename... _ArgTypes>
function<_Res(_ArgTypes...)>::
function(const function& __x)
: _Function_base()
{
if (static_cast<bool>(__x))
{
__x._M_manager(_M_functor, __x._M_functor, __clone_functor);
_M_invoker = __x._M_invoker;
_M_manager = __x._M_manager;
}
}
template<typename _Res, typename... _ArgTypes>
template<typename _Functor, typename, typename>
function<_Res(_ArgTypes...)>::
function(_Functor __f)
: _Function_base()
{
typedef _Function_handler<_Signature_type, _Functor> _My_handler;
if (_My_handler::_M_not_empty_function(__f))
{
_My_handler::_M_init_functor(_M_functor, std::move(__f));
_M_invoker = &_My_handler::_M_invoke;
_M_manager = &_My_handler::_M_manager;
}
}
template<typename _Res, typename... _ArgTypes>
_Res
function<_Res(_ArgTypes...)>::
operator()(_ArgTypes... __args) const
{
if (_M_empty())
__throw_bad_function_call();
return _M_invoker(_M_functor, std::forward<_ArgTypes>(__args)...);
}
#if __cpp_rtti
template<typename _Res, typename... _ArgTypes>
const type_info&
function<_Res(_ArgTypes...)>::
target_type() const noexcept
{
if (_M_manager)
{
_Any_data __typeinfo_result;
_M_manager(__typeinfo_result, _M_functor, __get_type_info);
return *__typeinfo_result._M_access<const type_info*>();
}
else
return typeid(void);
}
template<typename _Res, typename... _ArgTypes>
template<typename _Functor>
_Functor*
function<_Res(_ArgTypes...)>::
target() noexcept
{
if (typeid(_Functor) == target_type() && _M_manager)
{
_Any_data __ptr;
if (_M_manager(__ptr, _M_functor, __get_functor_ptr)
&& !is_const<_Functor>::value)
return 0;
else
return __ptr._M_access<_Functor*>();
}
else
return 0;
}
template<typename _Res, typename... _ArgTypes>
template<typename _Functor>
const _Functor*
function<_Res(_ArgTypes...)>::
target() const noexcept
{
if (typeid(_Functor) == target_type() && _M_manager)
{
_Any_data __ptr;
_M_manager(__ptr, _M_functor, __get_functor_ptr);
return __ptr._M_access<const _Functor*>();
}
else
return 0;
}
#endif
// [20.7.15.2.6] null pointer comparisons
/**
* @brief Compares a polymorphic function object wrapper against 0
* (the NULL pointer).
* @returns @c true if the wrapper has no target, @c false otherwise
*
* This function will not throw an %exception.
*/
template<typename _Res, typename... _Args>
inline bool
operator==(const function<_Res(_Args...)>& __f, nullptr_t) noexcept
{ return !static_cast<bool>(__f); }
/// @overload
template<typename _Res, typename... _Args>
inline bool
operator==(nullptr_t, const function<_Res(_Args...)>& __f) noexcept
{ return !static_cast<bool>(__f); }
/**
* @brief Compares a polymorphic function object wrapper against 0
* (the NULL pointer).
* @returns @c false if the wrapper has no target, @c true otherwise
*
* This function will not throw an %exception.
*/
template<typename _Res, typename... _Args>
inline bool
operator!=(const function<_Res(_Args...)>& __f, nullptr_t) noexcept
{ return static_cast<bool>(__f); }
/// @overload
template<typename _Res, typename... _Args>
inline bool
operator!=(nullptr_t, const function<_Res(_Args...)>& __f) noexcept
{ return static_cast<bool>(__f); }
// [20.7.15.2.7] specialized algorithms
/**
* @brief Swap the targets of two polymorphic function object wrappers.
*
* This function will not throw an %exception.
*/
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 2062. Effect contradictions w/o no-throw guarantee of std::function swaps
template<typename _Res, typename... _Args>
inline void
swap(function<_Res(_Args...)>& __x, function<_Res(_Args...)>& __y) noexcept
{ __x.swap(__y); }
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // C++11
#endif // _GLIBCXX_FUNCTIONAL