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// <tuple> -*- C++ -*-
// Copyright (C) 2007, 2008, 2009, 2010 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/>.
/** @file include/tuple
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_TUPLE
#define _GLIBCXX_TUPLE 1
#pragma GCC system_header
#ifndef __GXX_EXPERIMENTAL_CXX0X__
# include <bits/c++0x_warning.h>
#else
#include <utility>
namespace std
{
// Adds a const reference to a non-reference type.
template<typename _Tp>
struct __add_c_ref
{ typedef const _Tp& type; };
template<typename _Tp>
struct __add_c_ref<_Tp&>
{ typedef _Tp& type; };
// Adds a reference to a non-reference type.
template<typename _Tp>
struct __add_ref
{ typedef _Tp& type; };
template<typename _Tp>
struct __add_ref<_Tp&>
{ typedef _Tp& type; };
template<std::size_t _Idx, typename _Head, bool _IsEmpty>
struct _Head_base;
template<std::size_t _Idx, typename _Head>
struct _Head_base<_Idx, _Head, true>
: public _Head
{
_Head_base()
: _Head() { }
_Head_base(const _Head& __h)
: _Head(__h) { }
template<typename _UHead>
_Head_base(_UHead&& __h)
: _Head(std::forward<_UHead>(__h)) { }
_Head& _M_head() { return *this; }
const _Head& _M_head() const { return *this; }
void _M_swap_impl(_Head&) { /* no-op */ }
};
template<std::size_t _Idx, typename _Head>
struct _Head_base<_Idx, _Head, false>
{
_Head_base()
: _M_head_impl() { }
_Head_base(const _Head& __h)
: _M_head_impl(__h) { }
template<typename _UHead>
_Head_base(_UHead&& __h)
: _M_head_impl(std::forward<_UHead>(__h)) { }
_Head& _M_head() { return _M_head_impl; }
const _Head& _M_head() const { return _M_head_impl; }
void
_M_swap_impl(_Head& __h)
{
using std::swap;
swap(__h, _M_head_impl);
}
_Head _M_head_impl;
};
/**
* Contains the actual implementation of the @c tuple template, stored
* as a recursive inheritance hierarchy from the first element (most
* derived class) to the last (least derived class). The @c Idx
* parameter gives the 0-based index of the element stored at this
* point in the hierarchy; we use it to implement a constant-time
* get() operation.
*/
template<std::size_t _Idx, typename... _Elements>
struct _Tuple_impl;
/**
* Zero-element tuple implementation. This is the basis case for the
* inheritance recursion.
*/
template<std::size_t _Idx>
struct _Tuple_impl<_Idx>
{
protected:
void _M_swap_impl(_Tuple_impl&) { /* no-op */ }
};
/**
* Recursive tuple implementation. Here we store the @c Head element
* and derive from a @c Tuple_impl containing the remaining elements
* (which contains the @c Tail).
*/
template<std::size_t _Idx, typename _Head, typename... _Tail>
struct _Tuple_impl<_Idx, _Head, _Tail...>
: public _Tuple_impl<_Idx + 1, _Tail...>,
private _Head_base<_Idx, _Head, std::is_empty<_Head>::value>
{
typedef _Tuple_impl<_Idx + 1, _Tail...> _Inherited;
typedef _Head_base<_Idx, _Head, std::is_empty<_Head>::value> _Base;
_Head& _M_head() { return _Base::_M_head(); }
const _Head& _M_head() const { return _Base::_M_head(); }
_Inherited& _M_tail() { return *this; }
const _Inherited& _M_tail() const { return *this; }
_Tuple_impl()
: _Inherited(), _Base() { }
explicit
_Tuple_impl(const _Head& __head, const _Tail&... __tail)
: _Inherited(__tail...), _Base(__head) { }
template<typename _UHead, typename... _UTail>
explicit
_Tuple_impl(_UHead&& __head, _UTail&&... __tail)
: _Inherited(std::forward<_UTail>(__tail)...),
_Base(std::forward<_UHead>(__head)) { }
_Tuple_impl(const _Tuple_impl& __in)
: _Inherited(__in._M_tail()), _Base(__in._M_head()) { }
_Tuple_impl(_Tuple_impl&& __in)
: _Inherited(std::move(__in._M_tail())),
_Base(std::forward<_Head>(__in._M_head())) { }
template<typename... _UElements>
_Tuple_impl(const _Tuple_impl<_Idx, _UElements...>& __in)
: _Inherited(__in._M_tail()), _Base(__in._M_head()) { }
template<typename... _UElements>
_Tuple_impl(_Tuple_impl<_Idx, _UElements...>&& __in)
: _Inherited(std::move(__in._M_tail())),
_Base(std::move(__in._M_head())) { }
_Tuple_impl&
operator=(const _Tuple_impl& __in)
{
_M_head() = __in._M_head();
_M_tail() = __in._M_tail();
return *this;
}
_Tuple_impl&
operator=(_Tuple_impl&& __in)
{
_M_head() = std::move(__in._M_head());
_M_tail() = std::move(__in._M_tail());
return *this;
}
template<typename... _UElements>
_Tuple_impl&
operator=(const _Tuple_impl<_Idx, _UElements...>& __in)
{
_M_head() = __in._M_head();
_M_tail() = __in._M_tail();
return *this;
}
template<typename... _UElements>
_Tuple_impl&
operator=(_Tuple_impl<_Idx, _UElements...>&& __in)
{
_M_head() = std::move(__in._M_head());
_M_tail() = std::move(__in._M_tail());
return *this;
}
protected:
void
_M_swap_impl(_Tuple_impl& __in)
{
_Base::_M_swap_impl(__in._M_head());
_Inherited::_M_swap_impl(__in._M_tail());
}
};
/// tuple
template<typename... _Elements>
class tuple : public _Tuple_impl<0, _Elements...>
{
typedef _Tuple_impl<0, _Elements...> _Inherited;
public:
tuple()
: _Inherited() { }
explicit
tuple(const _Elements&... __elements)
: _Inherited(__elements...) { }
template<typename... _UElements>
explicit
tuple(_UElements&&... __elements)
: _Inherited(std::forward<_UElements>(__elements)...) { }
tuple(const tuple& __in)
: _Inherited(static_cast<const _Inherited&>(__in)) { }
tuple(tuple&& __in)
: _Inherited(static_cast<_Inherited&&>(__in)) { }
template<typename... _UElements>
tuple(const tuple<_UElements...>& __in)
: _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
{ }
template<typename... _UElements>
tuple(tuple<_UElements...>&& __in)
: _Inherited(static_cast<_Tuple_impl<0, _UElements...>&&>(__in)) { }
// XXX http://gcc.gnu.org/ml/libstdc++/2008-02/msg00047.html
template<typename... _UElements>
tuple(tuple<_UElements...>& __in)
: _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
{ }
tuple&
operator=(const tuple& __in)
{
static_cast<_Inherited&>(*this) = __in;
return *this;
}
tuple&
operator=(tuple&& __in)
{
static_cast<_Inherited&>(*this) = std::move(__in);
return *this;
}
template<typename... _UElements>
tuple&
operator=(const tuple<_UElements...>& __in)
{
static_cast<_Inherited&>(*this) = __in;
return *this;
}
template<typename... _UElements>
tuple&
operator=(tuple<_UElements...>&& __in)
{
static_cast<_Inherited&>(*this) = std::move(__in);
return *this;
}
void
swap(tuple& __in)
{ _Inherited::_M_swap_impl(__in); }
};
template<>
class tuple<>
{
public:
void swap(tuple&) { /* no-op */ }
};
/// tuple (2-element), with construction and assignment from a pair.
template<typename _T1, typename _T2>
class tuple<_T1, _T2> : public _Tuple_impl<0, _T1, _T2>
{
typedef _Tuple_impl<0, _T1, _T2> _Inherited;
public:
tuple()
: _Inherited() { }
explicit
tuple(const _T1& __a1, const _T2& __a2)
: _Inherited(__a1, __a2) { }
template<typename _U1, typename _U2>
explicit
tuple(_U1&& __a1, _U2&& __a2)
: _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { }
tuple(const tuple& __in)
: _Inherited(static_cast<const _Inherited&>(__in)) { }
tuple(tuple&& __in)
: _Inherited(static_cast<_Inherited&&>(__in)) { }
template<typename _U1, typename _U2>
tuple(const tuple<_U1, _U2>& __in)
: _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { }
template<typename _U1, typename _U2>
tuple(tuple<_U1, _U2>&& __in)
: _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { }
template<typename _U1, typename _U2>
tuple(const pair<_U1, _U2>& __in)
: _Inherited(__in.first, __in.second) { }
template<typename _U1, typename _U2>
tuple(pair<_U1, _U2>&& __in)
: _Inherited(std::forward<_U1>(__in.first),
std::forward<_U2>(__in.second)) { }
tuple&
operator=(const tuple& __in)
{
static_cast<_Inherited&>(*this) = __in;
return *this;
}
tuple&
operator=(tuple&& __in)
{
static_cast<_Inherited&>(*this) = std::move(__in);
return *this;
}
template<typename _U1, typename _U2>
tuple&
operator=(const tuple<_U1, _U2>& __in)
{
static_cast<_Inherited&>(*this) = __in;
return *this;
}
template<typename _U1, typename _U2>
tuple&
operator=(tuple<_U1, _U2>&& __in)
{
static_cast<_Inherited&>(*this) = std::move(__in);
return *this;
}
template<typename _U1, typename _U2>
tuple&
operator=(const pair<_U1, _U2>& __in)
{
this->_M_head() = __in.first;
this->_M_tail()._M_head() = __in.second;
return *this;
}
template<typename _U1, typename _U2>
tuple&
operator=(pair<_U1, _U2>&& __in)
{
this->_M_head() = std::move(__in.first);
this->_M_tail()._M_head() = std::move(__in.second);
return *this;
}
void
swap(tuple& __in)
{
using std::swap;
swap(this->_M_head(), __in._M_head());
swap(this->_M_tail()._M_head(), __in._M_tail()._M_head());
}
};
/// Gives the type of the ith element of a given tuple type.
template<std::size_t __i, typename _Tp>
struct tuple_element;
/**
* Recursive case for tuple_element: strip off the first element in
* the tuple and retrieve the (i-1)th element of the remaining tuple.
*/
template<std::size_t __i, typename _Head, typename... _Tail>
struct tuple_element<__i, tuple<_Head, _Tail...> >
: tuple_element<__i - 1, tuple<_Tail...> > { };
/**
* Basis case for tuple_element: The first element is the one we're seeking.
*/
template<typename _Head, typename... _Tail>
struct tuple_element<0, tuple<_Head, _Tail...> >
{
typedef _Head type;
};
/// Finds the size of a given tuple type.
template<typename _Tp>
struct tuple_size;
/// class tuple_size
template<typename... _Elements>
struct tuple_size<tuple<_Elements...> >
{
static const std::size_t value = sizeof...(_Elements);
};
template<typename... _Elements>
const std::size_t tuple_size<tuple<_Elements...> >::value;
template<std::size_t __i, typename _Head, typename... _Tail>
inline typename __add_ref<_Head>::type
__get_helper(_Tuple_impl<__i, _Head, _Tail...>& __t)
{ return __t._M_head(); }
template<std::size_t __i, typename _Head, typename... _Tail>
inline typename __add_c_ref<_Head>::type
__get_helper(const _Tuple_impl<__i, _Head, _Tail...>& __t)
{ return __t._M_head(); }
// Return a reference (const reference) to the ith element of a tuple.
// Any const or non-const ref elements are returned with their original type.
template<std::size_t __i, typename... _Elements>
inline typename __add_ref<
typename tuple_element<__i, tuple<_Elements...> >::type
>::type
get(tuple<_Elements...>& __t)
{ return __get_helper<__i>(__t); }
template<std::size_t __i, typename... _Elements>
inline typename __add_c_ref<
typename tuple_element<__i, tuple<_Elements...> >::type
>::type
get(const tuple<_Elements...>& __t)
{ return __get_helper<__i>(__t); }
// This class helps construct the various comparison operations on tuples
template<std::size_t __check_equal_size, std::size_t __i, std::size_t __j,
typename _Tp, typename _Up>
struct __tuple_compare;
template<std::size_t __i, std::size_t __j, typename _Tp, typename _Up>
struct __tuple_compare<0, __i, __j, _Tp, _Up>
{
static bool __eq(const _Tp& __t, const _Up& __u)
{
return (get<__i>(__t) == get<__i>(__u) &&
__tuple_compare<0, __i + 1, __j, _Tp, _Up>::__eq(__t, __u));
}
static bool __less(const _Tp& __t, const _Up& __u)
{
return ((get<__i>(__t) < get<__i>(__u))
|| !(get<__i>(__u) < get<__i>(__t)) &&
__tuple_compare<0, __i + 1, __j, _Tp, _Up>::__less(__t, __u));
}
};
template<std::size_t __i, typename _Tp, typename _Up>
struct __tuple_compare<0, __i, __i, _Tp, _Up>
{
static bool __eq(const _Tp&, const _Up&)
{ return true; }
static bool __less(const _Tp&, const _Up&)
{ return false; }
};
template<typename... _TElements, typename... _UElements>
bool
operator==(const tuple<_TElements...>& __t,
const tuple<_UElements...>& __u)
{
typedef tuple<_TElements...> _Tp;
typedef tuple<_UElements...> _Up;
return (__tuple_compare<tuple_size<_Tp>::value - tuple_size<_Up>::value,
0, tuple_size<_Tp>::value, _Tp, _Up>::__eq(__t, __u));
}
template<typename... _TElements, typename... _UElements>
bool
operator<(const tuple<_TElements...>& __t,
const tuple<_UElements...>& __u)
{
typedef tuple<_TElements...> _Tp;
typedef tuple<_UElements...> _Up;
return (__tuple_compare<tuple_size<_Tp>::value - tuple_size<_Up>::value,
0, tuple_size<_Tp>::value, _Tp, _Up>::__less(__t, __u));
}
template<typename... _TElements, typename... _UElements>
inline bool
operator!=(const tuple<_TElements...>& __t,
const tuple<_UElements...>& __u)
{ return !(__t == __u); }
template<typename... _TElements, typename... _UElements>
inline bool
operator>(const tuple<_TElements...>& __t,
const tuple<_UElements...>& __u)
{ return __u < __t; }
template<typename... _TElements, typename... _UElements>
inline bool
operator<=(const tuple<_TElements...>& __t,
const tuple<_UElements...>& __u)
{ return !(__u < __t); }
template<typename... _TElements, typename... _UElements>
inline bool
operator>=(const tuple<_TElements...>& __t,
const tuple<_UElements...>& __u)
{ return !(__t < __u); }
// NB: DR 705.
template<typename... _Elements>
inline tuple<typename __decay_and_strip<_Elements>::__type...>
make_tuple(_Elements&&... __args)
{
typedef tuple<typename __decay_and_strip<_Elements>::__type...>
__result_type;
return __result_type(std::forward<_Elements>(__args)...);
}
template<std::size_t...> struct __index_holder { };
template<std::size_t __i, typename _IdxHolder, typename... _Elements>
struct __index_holder_impl;
template<std::size_t __i, std::size_t... _Indexes, typename _IdxHolder,
typename... _Elements>
struct __index_holder_impl<__i, __index_holder<_Indexes...>,
_IdxHolder, _Elements...>
{
typedef typename __index_holder_impl<__i + 1,
__index_holder<_Indexes..., __i>,
_Elements...>::type type;
};
template<std::size_t __i, std::size_t... _Indexes>
struct __index_holder_impl<__i, __index_holder<_Indexes...> >
{ typedef __index_holder<_Indexes...> type; };
template<typename... _Elements>
struct __make_index_holder
: __index_holder_impl<0, __index_holder<>, _Elements...> { };
template<typename... _TElements, std::size_t... _TIdx,
typename... _UElements, std::size_t... _UIdx>
inline tuple<_TElements..., _UElements...>
__tuple_cat_helper(const tuple<_TElements...>& __t,
const __index_holder<_TIdx...>&,
const tuple<_UElements...>& __u,
const __index_holder<_UIdx...>&)
{ return tuple<_TElements..., _UElements...>(get<_TIdx>(__t)...,
get<_UIdx>(__u)...); }
template<typename... _TElements, std::size_t... _TIdx,
typename... _UElements, std::size_t... _UIdx>
inline tuple<_TElements..., _UElements...>
__tuple_cat_helper(tuple<_TElements...>&& __t,
const __index_holder<_TIdx...>&,
const tuple<_UElements...>& __u,
const __index_holder<_UIdx...>&)
{ return tuple<_TElements..., _UElements...>
(std::move(get<_TIdx>(__t))..., get<_UIdx>(__u)...); }
template<typename... _TElements, std::size_t... _TIdx,
typename... _UElements, std::size_t... _UIdx>
inline tuple<_TElements..., _UElements...>
__tuple_cat_helper(const tuple<_TElements...>& __t,
const __index_holder<_TIdx...>&,
tuple<_UElements...>&& __u,
const __index_holder<_UIdx...>&)
{ return tuple<_TElements..., _UElements...>
(get<_TIdx>(__t)..., std::move(get<_UIdx>(__u))...); }
template<typename... _TElements, std::size_t... _TIdx,
typename... _UElements, std::size_t... _UIdx>
inline tuple<_TElements..., _UElements...>
__tuple_cat_helper(tuple<_TElements...>&& __t,
const __index_holder<_TIdx...>&,
tuple<_UElements...>&& __u,
const __index_holder<_UIdx...>&)
{ return tuple<_TElements..., _UElements...>
(std::move(get<_TIdx>(__t))..., std::move(get<_UIdx>(__u))...); }
template<typename... _TElements, typename... _UElements>
inline tuple<_TElements..., _UElements...>
tuple_cat(const tuple<_TElements...>& __t, const tuple<_UElements...>& __u)
{
return __tuple_cat_helper(__t, typename
__make_index_holder<_TElements...>::type(),
__u, typename
__make_index_holder<_UElements...>::type());
}
template<typename... _TElements, typename... _UElements>
inline tuple<_TElements..., _UElements...>
tuple_cat(tuple<_TElements...>&& __t, const tuple<_UElements...>& __u)
{
return __tuple_cat_helper(std::move(__t), typename
__make_index_holder<_TElements...>::type(),
__u, typename
__make_index_holder<_UElements...>::type());
}
template<typename... _TElements, typename... _UElements>
inline tuple<_TElements..., _UElements...>
tuple_cat(const tuple<_TElements...>& __t, tuple<_UElements...>&& __u)
{
return __tuple_cat_helper(__t, typename
__make_index_holder<_TElements...>::type(),
std::move(__u), typename
__make_index_holder<_UElements...>::type());
}
template<typename... _TElements, typename... _UElements>
inline tuple<_TElements..., _UElements...>
tuple_cat(tuple<_TElements...>&& __t, tuple<_UElements...>&& __u)
{
return __tuple_cat_helper(std::move(__t), typename
__make_index_holder<_TElements...>::type(),
std::move(__u), typename
__make_index_holder<_UElements...>::type());
}
template<typename... _Elements>
inline tuple<_Elements&...>
tie(_Elements&... __args)
{ return tuple<_Elements&...>(__args...); }
template<typename... _Elements>
inline void
swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y)
{ __x.swap(__y); }
// A class (and instance) which can be used in 'tie' when an element
// of a tuple is not required
struct _Swallow_assign
{
template<class _Tp>
_Swallow_assign&
operator=(const _Tp&)
{ return *this; }
};
// TODO: Put this in some kind of shared file.
namespace
{
_Swallow_assign ignore;
}; // anonymous namespace
}
#endif // __GXX_EXPERIMENTAL_CXX0X__
#endif // _GLIBCXX_TUPLE