_iterator.h

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#ifndef _RWSTD_RW_ITERATOR_H_INCLUDED
#define _RWSTD_RW_ITERATOR_H_INCLUDED
 
#ifndef _RWSTD_RW_ITERBASE_H_INCLUDED
#  include <rw/_iterbase.h>
#endif   // _RWSTD_RW_ITERBASE_H_INCLUDED
 
 
_RWSTD_NAMESPACE (std) { 
 
 
// Reverse iterator.     
 
//
//  Macros for reverse iterators to accomodate non-standard compilers
//
#ifndef _RWSTD_NO_CLASS_PARTIAL_SPEC 
#  define _RWSTD_ITER_TEMPLATE template <class _Iterator>
#  define _RWSTD_ITER_ID(i)    i <_Iterator>
#  define _RWSTD_ITER_DIFF_TYPE(i, ignore)                             \
          typename iterator_traits<_Iterator>::difference_type
#else
#  define _RWSTD_ITER_TEMPLATE                                         \
          template <class _Iterator, class _Category, class _TypeT,    \
                    class _Reference, class _Pointer, class _Distance>
#  define _RWSTD_ITER_ID(i)                                            \
          i <_Iterator, _Category, _TypeT, _Reference, _Pointer, _Distance>
#  define _RWSTD_ITER_DIFF_TYPE(ignore, distance) distance          
#endif   // _RWSTD_NO_CLASS_PARTIAL_SPEC 
 
 
#ifndef _RWSTD_NO_CLASS_PARTIAL_SPEC 
 
template <class _Iterator>
class reverse_iterator
    : public iterator<typename iterator_traits<_Iterator>::iterator_category, 
                      typename iterator_traits<_Iterator>::value_type, 
                      typename iterator_traits<_Iterator>::difference_type,
                      typename iterator_traits<_Iterator>::pointer, 
                      typename iterator_traits<_Iterator>::reference>
{
    typedef iterator_traits<_Iterator>             traits_type;
public:
    typedef typename traits_type::difference_type difference_type;
    typedef typename traits_type::value_type      value_type;
    typedef typename traits_type::pointer         pointer;
    typedef typename traits_type::reference       reference;
 
#else   // if defined (_RWSTD_NO_CLASS_PARTIAL_SPEC)
 
template <class _Iterator, class _Category, class _TypeT,
          class _Reference = _TypeT&, 
          class _Pointer = _TypeT*,
          class _Distance = _RWSTD_PTRDIFF_T>
class reverse_iterator
    : public iterator<_Category, _TypeT, _Distance, _Pointer, _Reference>
 
{
public:
    typedef _Distance  difference_type;
    typedef _TypeT     value_type;
    typedef _Reference reference;
    typedef _Pointer   pointer;
 
#endif   // _RWSTD_NO_CLASS_PARTIAL_SPEC
 
    typedef _Iterator iterator_type;
 
    reverse_iterator () { }
 
    // 24.4.1.3.1, p1
    explicit reverse_iterator (iterator_type __rhs) : current (__rhs) { }
 
 
#ifndef _RWSTD_NO_CLASS_PARTIAL_SPEC 
 
    // 24.4.1.3.1, p2
    template <class _TypeU>
    reverse_iterator (const reverse_iterator<_TypeU>& __rhs)
        : current (__rhs.base ()) { }
 
#else   // if defined (_RWSTD_NO_CLASS_PARTIAL_SPEC)
 
    // 24.4.1.3.1, p2
    template <class _Iterator2, class _Category2, class _TypeU,
              class _Reference2, class _Pointer2, class _Distance2>
    reverse_iterator (const reverse_iterator<_Iterator2, _Category2, _TypeU,
                      _Reference2, _Pointer2, _Distance2>& __rhs)
        : current (__rhs.base ()) { }
 
#endif   // _RWSTD_NO_CLASS_PARTIAL_SPEC 
 
 
    // 24.4.1.3.2, p1
    iterator_type base () const {
        return current;
    }
 
    // 24.4.1.3.3, p1
    reference operator* () const {
        iterator_type __tmp (base ());
        return *--__tmp;
    }
 
    // 24.4.1.3.4, p1
    _RWSTD_OPERATOR_ARROW (pointer operator->() const);
 
    // 24.4.1.3.5, p1
    reverse_iterator& operator++ () {
        return --current, *this;
    }
 
    // 24.4.1.3.5, p3
    reverse_iterator operator++ (int) {
        reverse_iterator __tmp (*this);
        return ++*this, __tmp;
    }
 
    // 24.4.1.3.6, p1
    reverse_iterator& operator-- () {
        return ++current, *this;
    }
 
    // 24.4.1.3.6, p3
    reverse_iterator operator-- (int) {
        reverse_iterator __tmp (*this);
        return --*this, __tmp;
    }
 
    // 24.4.1.3.8, p1
    reverse_iterator& operator+= (difference_type __n) {
        return current -= __n, *this;
    }
 
    // 24.4.1.3.10, p1
    reverse_iterator& operator-= (difference_type __n) {
        return *this += -__n;
    }
 
    // 24.4.1.3.7, p1
    reverse_iterator operator+ (difference_type __n) const {
        return reverse_iterator (*this) += __n;
    }
 
    // 24.4.1.3.9, p1
    reverse_iterator operator- (difference_type __n) const {
        return reverse_iterator (*this) -= __n;
    }
 
    // 24.4.1.3.11, p1
    reference operator[] (difference_type __n) const {
        return *(*this + __n);
    }
 
protected:
 
    iterator_type current;
};
 
 
// 24.4.1.3.12
_RWSTD_ITER_TEMPLATE
inline bool operator== (const _RWSTD_ITER_ID (reverse_iterator)& __x,
                        const _RWSTD_ITER_ID (reverse_iterator)& __y)
{
    return __x.base () == __y.base ();
}
 
 
// 24.4.1.3.13
_RWSTD_ITER_TEMPLATE
inline bool operator< (const _RWSTD_ITER_ID (reverse_iterator)& __x,
                       const _RWSTD_ITER_ID (reverse_iterator)& __y)
{
    return __y.base() < __x.base();
}
 
 
// 24.4.1.3.14
_RWSTD_ITER_TEMPLATE
inline bool operator!= (const _RWSTD_ITER_ID (reverse_iterator)& __x, 
                        const _RWSTD_ITER_ID (reverse_iterator)& __y)
{
    return !(__x == __y);
}
 
 
// 24.4.1.3.15
_RWSTD_ITER_TEMPLATE
inline bool operator> (const _RWSTD_ITER_ID (reverse_iterator)& __x, 
                       const _RWSTD_ITER_ID (reverse_iterator)& __y)
{
    return __y < __x;
}
 
 
// 24.4.1.3.16
_RWSTD_ITER_TEMPLATE
inline bool operator>= (const _RWSTD_ITER_ID (reverse_iterator)& __x, 
                        const _RWSTD_ITER_ID (reverse_iterator)& __y)
{
    return !(__x < __y);
}
 
 
// 24.4.1.3.17
_RWSTD_ITER_TEMPLATE
inline bool operator<= (const _RWSTD_ITER_ID (reverse_iterator)& __x,
                        const _RWSTD_ITER_ID (reverse_iterator)& __y)
{
    return !(__y < __x);
}
 
 
// 24.4.1.3.18
_RWSTD_ITER_TEMPLATE
inline _RWSTD_ITER_DIFF_TYPE (_Iterator, _Distance)
operator- (const _RWSTD_ITER_ID (reverse_iterator)& __x, 
           const _RWSTD_ITER_ID (reverse_iterator)& __y)
{
    return __y.base () - __x.base ();
}
 
 
// 24.4.1.3.19
_RWSTD_ITER_TEMPLATE
inline _RWSTD_ITER_ID (reverse_iterator)
operator+ (_RWSTD_ITER_DIFF_TYPE (_Iterator, _Distance) __n, 
           const _RWSTD_ITER_ID (reverse_iterator)&     __x)
{
    return __x + __n;
}
 
#undef _RWSTD_ITER_DIFF_TYPE
 
#ifdef _RWSTD_NO_CLASS_PARTIAL_SPEC
 
}   // namespace std
 
_RWSTD_NAMESPACE (__rw) { 
 
// Reverse bidirectional iterator.       
// This is needed to get around non-standard compilers that insist
// on instantiating all members of a class whether they're used 
// or not.
 
template <class _Iterator, class _Category, class _TypeT, 
          class _Reference = _TypeT&, 
          class _Pointer = _TypeT*, 
          class _Distance = _RWSTD_PTRDIFF_T>
class __reverse_bi_iterator
    : public _STD::iterator<_Category, _TypeT, _Distance, _Pointer, _Reference>
{
public:
    typedef _Distance  difference_type;
    typedef _TypeT     value_type;
    typedef _Reference reference;
    typedef _Pointer   pointer;
    typedef _Iterator  iterator_type;
 
    __reverse_bi_iterator () { }
 
    explicit __reverse_bi_iterator (const iterator_type &__rhs) 
        : current (__rhs) { }
 
 
#ifndef _RWSTD_NO_CLASS_PARTIAL_SPEC 
 
      template <class _TypeU>
      __reverse_bi_iterator (const __reverse_bi_iterator<_TypeU>& __rhs)
          : current (__rhs.base ()) { }
 
#else   // if defined (_RWSTD_NO_CLASS_PARTIAL_SPEC )
 
      template <class _Iterator2, class _Category2, class _TypeU,
                class _Reference2, class _Pointer2, class _Distance2>
      __reverse_bi_iterator (const __reverse_bi_iterator<_Iterator2,
                                                         _Category2,
                                                         _TypeU,
                                                         _Reference2,
                                                         _Pointer2,
                                                         _Distance2>& __rhs)
          : current (__rhs.base ()) { }
#endif
 
 
    iterator_type base () const {
        return current;
    }
 
    reference operator* () const {
        iterator_type __tmp = base ();
        return *--__tmp;
    }
 
    _RWSTD_OPERATOR_ARROW (pointer operator->() const);
 
    __reverse_bi_iterator& operator++ () {
        return --current, *this;
    }
 
    __reverse_bi_iterator  operator++ (int) {
        __reverse_bi_iterator __tmp (*this);
        ++*this;
        return __tmp;
    }
 
    __reverse_bi_iterator& operator-- () {
        return ++current, *this;
    }
 
    __reverse_bi_iterator operator-- (int) {
        __reverse_bi_iterator __tmp (*this);
        --*this;
        return __tmp;
    }
 
protected:
 
    iterator_type current;
};
 
 
_RWSTD_ITER_TEMPLATE
inline bool operator== (const _RWSTD_ITER_ID (__reverse_bi_iterator)& __x, 
                        const _RWSTD_ITER_ID (__reverse_bi_iterator)& __y)
{
    return __x.base () == __y.base ();
}
 
 
_RWSTD_ITER_TEMPLATE
inline bool operator!= (const _RWSTD_ITER_ID (__reverse_bi_iterator)& __x,
                        const _RWSTD_ITER_ID (__reverse_bi_iterator)& __y)
{
    return !(__x == __y);
}
 
#undef _RWSTD_ITER_TEMPLATE
#undef _RWSTD_ITER_ID
 
}   // namespace __rw
 
_RWSTD_NAMESPACE (std) { 
 
#endif   // _RWSTD_NO_CLASS_PARTIAL_SPEC
 
 
#ifndef _RWSTD_NO_CLASS_PARTIAL_SPEC
#  define _RWSTD_INSERT_ITERATOR_BASE(ignore)       \
          iterator<output_iterator_tag, void, void, void, void>
#else
   // necessary to allow __iterator_category, __value_type, etc. to work
#  define _RWSTD_INSERT_ITERATOR_BASE(cont)         \
          iterator<output_iterator_tag,             \
                   typename cont::value_type,      \
                   typename cont::difference_type, \
                   typename cont::pointer,         \
                   typename cont::reference>
#endif   // _RWSTD_NO_CLASS_PARTIAL_SPEC
 
 
template <class _Container>
class back_insert_iterator: public _RWSTD_INSERT_ITERATOR_BASE (_Container)
{
public:
    typedef _Container container_type;
 
    explicit back_insert_iterator (container_type& __rhs)
        : container (&__rhs) { }
 
    back_insert_iterator&
    operator= (typename container_type::const_reference __x) {
        return container->push_back (__x), *this;
    }
 
    back_insert_iterator& operator*  () {
        return *this;
    }
 
    back_insert_iterator& operator++ () {
        return *this;
    }
 
    back_insert_iterator operator++ (int) {
        return *this;
    }
 
protected:
 
    container_type* container;
};
 
 
template <class _Container>
inline back_insert_iterator<_Container> back_inserter (_Container& __x)
{
    return back_insert_iterator<_Container>(__x);
}
 
 
template <class _Container>
class front_insert_iterator: public _RWSTD_INSERT_ITERATOR_BASE (_Container)
{
public:
    typedef _Container container_type;
 
    explicit front_insert_iterator (container_type& __rhs)
        : container (&__rhs) { }
 
    front_insert_iterator&
    operator= (typename container_type::const_reference __x) { 
        return container->push_front (__x), *this;
    }
 
    front_insert_iterator& operator* () {
        return *this;
    }
 
    front_insert_iterator& operator++ () {
        return *this;
    }
 
    front_insert_iterator operator++ (int) {
        return *this;
    }
 
protected:
 
    container_type* container;
};
 
 
template <class _Container>
inline front_insert_iterator<_Container> front_inserter (_Container& __x)
{
    return front_insert_iterator<_Container>(__x);
}
 
 
template <class _Container>
class insert_iterator: public _RWSTD_INSERT_ITERATOR_BASE (_Container)
{
public:
    typedef _Container container_type;
 
    insert_iterator (container_type                    &__x,
                     typename container_type::iterator __it)
      : iter (__it), container (&__x) { }
 
    insert_iterator&
    operator= (typename container_type::const_reference __x) { 
        iter = container->insert (iter, __x);
        return ++iter, *this;
    }
 
    insert_iterator& operator* () {
        return *this;
    }
 
    insert_iterator& operator++ () {
        return *this;
    }
 
    insert_iterator& operator++ (int) {
        return *this;
    }
 
protected:
 
    typename container_type::iterator iter;
    container_type*                    container;
};
 
 
template <class _Container, class _Iterator>
inline insert_iterator<_Container> inserter (_Container& __x, _Iterator __it)
{
    typedef typename _Container::iterator _Iter;
 
    return insert_iterator<_Container> (__x, _Iter (__it));
}
 
 
}   // namespace std
 
#endif   // _RWSTD_RW_ITERATOR_H_INCLUDED