llvm-project/libcxx/include/__functional/bind.h

387 lines
12 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___FUNCTIONAL_BIND_H
#define _LIBCPP___FUNCTIONAL_BIND_H
#include <__config>
#include <__functional/weak_result_type.h>
#include <__functional/invoke.h>
#include <cstddef>
#include <tuple>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
template<class _Tp> struct __is_bind_expression : public false_type {};
template<class _Tp> struct _LIBCPP_TEMPLATE_VIS is_bind_expression
: public __is_bind_expression<typename remove_cv<_Tp>::type> {};
#if _LIBCPP_STD_VER > 14
template <class _Tp>
inline constexpr size_t is_bind_expression_v = is_bind_expression<_Tp>::value;
#endif
template<class _Tp> struct __is_placeholder : public integral_constant<int, 0> {};
template<class _Tp> struct _LIBCPP_TEMPLATE_VIS is_placeholder
: public __is_placeholder<typename remove_cv<_Tp>::type> {};
#if _LIBCPP_STD_VER > 14
template <class _Tp>
inline constexpr size_t is_placeholder_v = is_placeholder<_Tp>::value;
#endif
namespace placeholders
{
template <int _Np> struct __ph {};
#if defined(_LIBCPP_CXX03_LANG) || defined(_LIBCPP_BUILDING_LIBRARY)
_LIBCPP_FUNC_VIS extern const __ph<1> _1;
_LIBCPP_FUNC_VIS extern const __ph<2> _2;
_LIBCPP_FUNC_VIS extern const __ph<3> _3;
_LIBCPP_FUNC_VIS extern const __ph<4> _4;
_LIBCPP_FUNC_VIS extern const __ph<5> _5;
_LIBCPP_FUNC_VIS extern const __ph<6> _6;
_LIBCPP_FUNC_VIS extern const __ph<7> _7;
_LIBCPP_FUNC_VIS extern const __ph<8> _8;
_LIBCPP_FUNC_VIS extern const __ph<9> _9;
_LIBCPP_FUNC_VIS extern const __ph<10> _10;
#else
/* inline */ constexpr __ph<1> _1{};
/* inline */ constexpr __ph<2> _2{};
/* inline */ constexpr __ph<3> _3{};
/* inline */ constexpr __ph<4> _4{};
/* inline */ constexpr __ph<5> _5{};
/* inline */ constexpr __ph<6> _6{};
/* inline */ constexpr __ph<7> _7{};
/* inline */ constexpr __ph<8> _8{};
/* inline */ constexpr __ph<9> _9{};
/* inline */ constexpr __ph<10> _10{};
#endif // defined(_LIBCPP_CXX03_LANG) || defined(_LIBCPP_BUILDING_LIBRARY)
} // placeholders
template<int _Np>
struct __is_placeholder<placeholders::__ph<_Np> >
: public integral_constant<int, _Np> {};
#ifndef _LIBCPP_CXX03_LANG
template <class _Tp, class _Uj>
inline _LIBCPP_INLINE_VISIBILITY
_Tp&
__mu(reference_wrapper<_Tp> __t, _Uj&)
{
return __t.get();
}
template <class _Ti, class ..._Uj, size_t ..._Indx>
inline _LIBCPP_INLINE_VISIBILITY
typename __invoke_of<_Ti&, _Uj...>::type
__mu_expand(_Ti& __ti, tuple<_Uj...>& __uj, __tuple_indices<_Indx...>)
{
return __ti(_VSTD::forward<_Uj>(_VSTD::get<_Indx>(__uj))...);
}
template <class _Ti, class ..._Uj>
inline _LIBCPP_INLINE_VISIBILITY
typename __enable_if_t
<
is_bind_expression<_Ti>::value,
__invoke_of<_Ti&, _Uj...>
>::type
__mu(_Ti& __ti, tuple<_Uj...>& __uj)
{
typedef typename __make_tuple_indices<sizeof...(_Uj)>::type __indices;
return _VSTD::__mu_expand(__ti, __uj, __indices());
}
template <bool IsPh, class _Ti, class _Uj>
struct __mu_return2 {};
template <class _Ti, class _Uj>
struct __mu_return2<true, _Ti, _Uj>
{
typedef typename tuple_element<is_placeholder<_Ti>::value - 1, _Uj>::type type;
};
template <class _Ti, class _Uj>
inline _LIBCPP_INLINE_VISIBILITY
typename enable_if
<
0 < is_placeholder<_Ti>::value,
typename __mu_return2<0 < is_placeholder<_Ti>::value, _Ti, _Uj>::type
>::type
__mu(_Ti&, _Uj& __uj)
{
const size_t _Indx = is_placeholder<_Ti>::value - 1;
return _VSTD::forward<typename tuple_element<_Indx, _Uj>::type>(_VSTD::get<_Indx>(__uj));
}
template <class _Ti, class _Uj>
inline _LIBCPP_INLINE_VISIBILITY
typename enable_if
<
!is_bind_expression<_Ti>::value &&
is_placeholder<_Ti>::value == 0 &&
!__is_reference_wrapper<_Ti>::value,
_Ti&
>::type
__mu(_Ti& __ti, _Uj&)
{
return __ti;
}
template <class _Ti, bool IsReferenceWrapper, bool IsBindEx, bool IsPh,
class _TupleUj>
struct __mu_return_impl;
template <bool _Invokable, class _Ti, class ..._Uj>
struct __mu_return_invokable // false
{
typedef __nat type;
};
template <class _Ti, class ..._Uj>
struct __mu_return_invokable<true, _Ti, _Uj...>
{
typedef typename __invoke_of<_Ti&, _Uj...>::type type;
};
template <class _Ti, class ..._Uj>
struct __mu_return_impl<_Ti, false, true, false, tuple<_Uj...> >
: public __mu_return_invokable<__invokable<_Ti&, _Uj...>::value, _Ti, _Uj...>
{
};
template <class _Ti, class _TupleUj>
struct __mu_return_impl<_Ti, false, false, true, _TupleUj>
{
typedef typename tuple_element<is_placeholder<_Ti>::value - 1,
_TupleUj>::type&& type;
};
template <class _Ti, class _TupleUj>
struct __mu_return_impl<_Ti, true, false, false, _TupleUj>
{
typedef typename _Ti::type& type;
};
template <class _Ti, class _TupleUj>
struct __mu_return_impl<_Ti, false, false, false, _TupleUj>
{
typedef _Ti& type;
};
template <class _Ti, class _TupleUj>
struct __mu_return
: public __mu_return_impl<_Ti,
__is_reference_wrapper<_Ti>::value,
is_bind_expression<_Ti>::value,
0 < is_placeholder<_Ti>::value &&
is_placeholder<_Ti>::value <= tuple_size<_TupleUj>::value,
_TupleUj>
{
};
template <class _Fp, class _BoundArgs, class _TupleUj>
struct __is_valid_bind_return
{
static const bool value = false;
};
template <class _Fp, class ..._BoundArgs, class _TupleUj>
struct __is_valid_bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj>
{
static const bool value = __invokable<_Fp,
typename __mu_return<_BoundArgs, _TupleUj>::type...>::value;
};
template <class _Fp, class ..._BoundArgs, class _TupleUj>
struct __is_valid_bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj>
{
static const bool value = __invokable<_Fp,
typename __mu_return<const _BoundArgs, _TupleUj>::type...>::value;
};
template <class _Fp, class _BoundArgs, class _TupleUj,
bool = __is_valid_bind_return<_Fp, _BoundArgs, _TupleUj>::value>
struct __bind_return;
template <class _Fp, class ..._BoundArgs, class _TupleUj>
struct __bind_return<_Fp, tuple<_BoundArgs...>, _TupleUj, true>
{
typedef typename __invoke_of
<
_Fp&,
typename __mu_return
<
_BoundArgs,
_TupleUj
>::type...
>::type type;
};
template <class _Fp, class ..._BoundArgs, class _TupleUj>
struct __bind_return<_Fp, const tuple<_BoundArgs...>, _TupleUj, true>
{
typedef typename __invoke_of
<
_Fp&,
typename __mu_return
<
const _BoundArgs,
_TupleUj
>::type...
>::type type;
};
template <class _Fp, class _BoundArgs, size_t ..._Indx, class _Args>
inline _LIBCPP_INLINE_VISIBILITY
typename __bind_return<_Fp, _BoundArgs, _Args>::type
__apply_functor(_Fp& __f, _BoundArgs& __bound_args, __tuple_indices<_Indx...>,
_Args&& __args)
{
return _VSTD::__invoke(__f, _VSTD::__mu(_VSTD::get<_Indx>(__bound_args), __args)...);
}
template<class _Fp, class ..._BoundArgs>
class __bind
#if _LIBCPP_STD_VER <= 17 || !defined(_LIBCPP_ABI_NO_BINDER_BASES)
: public __weak_result_type<typename decay<_Fp>::type>
#endif
{
protected:
typedef typename decay<_Fp>::type _Fd;
typedef tuple<typename decay<_BoundArgs>::type...> _Td;
private:
_Fd __f_;
_Td __bound_args_;
typedef typename __make_tuple_indices<sizeof...(_BoundArgs)>::type __indices;
public:
template <class _Gp, class ..._BA,
class = typename enable_if
<
is_constructible<_Fd, _Gp>::value &&
!is_same<typename remove_reference<_Gp>::type,
__bind>::value
>::type>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
explicit __bind(_Gp&& __f, _BA&& ...__bound_args)
: __f_(_VSTD::forward<_Gp>(__f)),
__bound_args_(_VSTD::forward<_BA>(__bound_args)...) {}
template <class ..._Args>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type
operator()(_Args&& ...__args)
{
return _VSTD::__apply_functor(__f_, __bound_args_, __indices(),
tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
}
template <class ..._Args>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type
operator()(_Args&& ...__args) const
{
return _VSTD::__apply_functor(__f_, __bound_args_, __indices(),
tuple<_Args&&...>(_VSTD::forward<_Args>(__args)...));
}
};
template<class _Fp, class ..._BoundArgs>
struct __is_bind_expression<__bind<_Fp, _BoundArgs...> > : public true_type {};
template<class _Rp, class _Fp, class ..._BoundArgs>
class __bind_r
: public __bind<_Fp, _BoundArgs...>
{
typedef __bind<_Fp, _BoundArgs...> base;
typedef typename base::_Fd _Fd;
typedef typename base::_Td _Td;
public:
typedef _Rp result_type;
template <class _Gp, class ..._BA,
class = typename enable_if
<
is_constructible<_Fd, _Gp>::value &&
!is_same<typename remove_reference<_Gp>::type,
__bind_r>::value
>::type>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
explicit __bind_r(_Gp&& __f, _BA&& ...__bound_args)
: base(_VSTD::forward<_Gp>(__f),
_VSTD::forward<_BA>(__bound_args)...) {}
template <class ..._Args>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
typename enable_if
<
is_convertible<typename __bind_return<_Fd, _Td, tuple<_Args&&...> >::type,
result_type>::value || is_void<_Rp>::value,
result_type
>::type
operator()(_Args&& ...__args)
{
typedef __invoke_void_return_wrapper<_Rp> _Invoker;
return _Invoker::__call(static_cast<base&>(*this), _VSTD::forward<_Args>(__args)...);
}
template <class ..._Args>
_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
typename enable_if
<
is_convertible<typename __bind_return<const _Fd, const _Td, tuple<_Args&&...> >::type,
result_type>::value || is_void<_Rp>::value,
result_type
>::type
operator()(_Args&& ...__args) const
{
typedef __invoke_void_return_wrapper<_Rp> _Invoker;
return _Invoker::__call(static_cast<base const&>(*this), _VSTD::forward<_Args>(__args)...);
}
};
template<class _Rp, class _Fp, class ..._BoundArgs>
struct __is_bind_expression<__bind_r<_Rp, _Fp, _BoundArgs...> > : public true_type {};
template<class _Fp, class ..._BoundArgs>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
__bind<_Fp, _BoundArgs...>
bind(_Fp&& __f, _BoundArgs&&... __bound_args)
{
typedef __bind<_Fp, _BoundArgs...> type;
return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
}
template<class _Rp, class _Fp, class ..._BoundArgs>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
__bind_r<_Rp, _Fp, _BoundArgs...>
bind(_Fp&& __f, _BoundArgs&&... __bound_args)
{
typedef __bind_r<_Rp, _Fp, _BoundArgs...> type;
return type(_VSTD::forward<_Fp>(__f), _VSTD::forward<_BoundArgs>(__bound_args)...);
}
#endif // _LIBCPP_CXX03_LANG
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___FUNCTIONAL_BIND_H