_pair.h

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// -*- C++ -*-
 
#ifndef _RWSTD_RW_PAIR_H_INCLUDED
#define _RWSTD_RW_PAIR_H_INCLUDED
 
#ifndef _RWSTD_RW_FUNCBASE_H_INCLUDED
#  include <rw/_funcbase.h>   // for less
#endif   // _RWSTD_RW_FUNCBASE_H_INCLUDED
 
 
_RWSTD_NAMESPACE (std) { 
 
 
// 20.2.2
template <class _TypeT, class _TypeU>
struct pair
{
    typedef _TypeT first_type;
    typedef _TypeU second_type;
 
    first_type  first;
    second_type second;
 
    // 20.2.2, p2
    pair ()
#ifndef _RWSTD_NO_EMPTY_MEM_INITIALIZER
        : first (/* lwg issue 265 */), second () { }
#else
        // assumes types satisfy the CopyConstructible requirements
        : first (first_type ()), second (second_type ()) { }
#endif   // _RWSTD_NO_EMPTY_MEM_INITIALIZER
 
    // 20.2.2, p3
    pair (const first_type &__x, const second_type &__y)
        : first (__x), second (__y) { }
 
    // 20.2.2, p4
    template <class _TypeX, class _TypeY>
    pair (const pair <_TypeX, _TypeY> &__rhs) 
        : first (__rhs.first), second (__rhs.second) { }
 
    // lwg issue 353
    template <class _TypeX, class _TypeY>
    pair<_TypeT, _TypeU>& operator= (const pair <_TypeX, _TypeY> &__rhs) {
        return first = __rhs.first, second = __rhs.second, *this;
    }
 
};
 
 
// 20.2.2, p5
template <class _TypeT, class _TypeU>
inline bool
operator== (const pair<_TypeT, _TypeU>& __x, const pair<_TypeT, _TypeU>& __y)
{ 
    return __x.first == __y.first && __x.second == __y.second; 
}
 
 
template <class _TypeT, class _TypeU>
inline bool
operator!= (const pair<_TypeT, _TypeU>& __x, const pair<_TypeT, _TypeU>& __y)
{ 
    return !(__x == __y);
}
 
 
// 20.2.2, p6
template <class _TypeT, class _TypeU>
inline bool
operator< (const pair<_TypeT, _TypeU>& __x, const pair<_TypeT, _TypeU>& __y)
{
    _STD::less<_TypeT> __lessT;
 
    // follows resolution of lwg issue 348
    return    __lessT (__x.first, __y.first)
           || (   !__lessT (__y.first, __x.first)
               &&  _STD::less<_TypeU>()(__x.second, __y.second));
}
 
 
template <class _TypeT, class _TypeU>
inline bool
operator> (const pair<_TypeT, _TypeU>& __x, const pair<_TypeT, _TypeU>& __y)
{ 
    return __y < __x;
}
 
 
template <class _TypeT, class _TypeU>
inline bool
operator>= (const pair<_TypeT, _TypeU>& __x, const pair<_TypeT, _TypeU>& __y)
{ 
    return !(__x < __y);
}
 
 
template <class _TypeT, class _TypeU>
inline bool
operator<= (const pair<_TypeT, _TypeU>& __x, const pair<_TypeT, _TypeU>& __y)
{ 
    return !(__y < __x);
}
 
 
// 20.2.2, p7, signature follows lwg issue 181
template <class _TypeT, class _TypeU>
inline pair<_TypeT, _TypeU>
make_pair (_TypeT __x, _TypeU __y)
{
    return pair<_TypeT, _TypeU>(__x, __y);
}
 
 
}   // namespace std
 
 
#endif   // _RWSTD_RW_PAIR_H_INCLUDED