gcc/libstdc++-v3/bits/stl_iterator_base.h

359 lines
12 KiB
C
Raw Normal View History

/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* 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. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996-1998
* 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.
*/
/* NOTE: This is an internal header file, included by other STL headers.
* You should not attempt to use it directly.
*/
#ifndef __SGI_STL_INTERNAL_ITERATOR_BASE_H
#define __SGI_STL_INTERNAL_ITERATOR_BASE_H
// This file contains all of the general iterator-related utilities.
// The internal file stl_iterator.h contains predefined iterators,
// such as front_insert_iterator and istream_iterator.
__STL_BEGIN_NAMESPACE
struct input_iterator_tag {};
struct output_iterator_tag {};
struct forward_iterator_tag : public input_iterator_tag {};
struct bidirectional_iterator_tag : public forward_iterator_tag {};
struct random_access_iterator_tag : public bidirectional_iterator_tag {};
// The base classes input_iterator, output_iterator, forward_iterator,
// bidirectional_iterator, and random_access_iterator are not part of
// the C++ standard. (They have been replaced by struct iterator.)
// They are included for backward compatibility with the HP STL.
template <class _Tp, class _Distance> struct input_iterator {
typedef input_iterator_tag iterator_category;
typedef _Tp value_type;
typedef _Distance difference_type;
typedef _Tp* pointer;
typedef _Tp& reference;
};
struct output_iterator {
typedef output_iterator_tag iterator_category;
typedef void value_type;
typedef void difference_type;
typedef void pointer;
typedef void reference;
};
template <class _Tp, class _Distance> struct forward_iterator {
typedef forward_iterator_tag iterator_category;
typedef _Tp value_type;
typedef _Distance difference_type;
typedef _Tp* pointer;
typedef _Tp& reference;
};
template <class _Tp, class _Distance> struct bidirectional_iterator {
typedef bidirectional_iterator_tag iterator_category;
typedef _Tp value_type;
typedef _Distance difference_type;
typedef _Tp* pointer;
typedef _Tp& reference;
};
template <class _Tp, class _Distance> struct random_access_iterator {
typedef random_access_iterator_tag iterator_category;
typedef _Tp value_type;
typedef _Distance difference_type;
typedef _Tp* pointer;
typedef _Tp& reference;
};
#ifdef __STL_USE_NAMESPACES
template <class _Category, class _Tp, class _Distance = ptrdiff_t,
class _Pointer = _Tp*, class _Reference = _Tp&>
struct iterator {
typedef _Category iterator_category;
typedef _Tp value_type;
typedef _Distance difference_type;
typedef _Pointer pointer;
typedef _Reference reference;
};
#endif /* __STL_USE_NAMESPACES */
#ifdef __STL_CLASS_PARTIAL_SPECIALIZATION
template <class _Iterator>
struct iterator_traits {
typedef typename _Iterator::iterator_category iterator_category;
typedef typename _Iterator::value_type value_type;
typedef typename _Iterator::difference_type difference_type;
typedef typename _Iterator::pointer pointer;
typedef typename _Iterator::reference reference;
};
template <class _Tp>
struct iterator_traits<_Tp*> {
typedef random_access_iterator_tag iterator_category;
typedef _Tp value_type;
typedef ptrdiff_t difference_type;
typedef _Tp* pointer;
typedef _Tp& reference;
};
template <class _Tp>
struct iterator_traits<const _Tp*> {
typedef random_access_iterator_tag iterator_category;
typedef _Tp value_type;
typedef ptrdiff_t difference_type;
typedef const _Tp* pointer;
typedef const _Tp& reference;
};
// The overloaded functions iterator_category, distance_type, and
// value_type are not part of the C++ standard. (They have been
// replaced by struct iterator_traits.) They are included for
// backward compatibility with the HP STL.
// We introduce internal names for these functions.
template <class _Iter>
inline typename iterator_traits<_Iter>::iterator_category
__iterator_category(const _Iter&)
{
typedef typename iterator_traits<_Iter>::iterator_category _Category;
return _Category();
}
template <class _Iter>
inline typename iterator_traits<_Iter>::difference_type*
__distance_type(const _Iter&)
{
return static_cast<typename iterator_traits<_Iter>::difference_type*>(0);
}
template <class _Iter>
inline typename iterator_traits<_Iter>::value_type*
__value_type(const _Iter&)
{
return static_cast<typename iterator_traits<_Iter>::value_type*>(0);
}
template <class _Iter>
inline typename iterator_traits<_Iter>::iterator_category
iterator_category(const _Iter& __i) { return __iterator_category(__i); }
template <class _Iter>
inline typename iterator_traits<_Iter>::difference_type*
distance_type(const _Iter& __i) { return __distance_type(__i); }
template <class _Iter>
inline typename iterator_traits<_Iter>::value_type*
value_type(const _Iter& __i) { return __value_type(__i); }
#define __ITERATOR_CATEGORY(__i) __iterator_category(__i)
#define __DISTANCE_TYPE(__i) __distance_type(__i)
#define __VALUE_TYPE(__i) __value_type(__i)
#else /* __STL_CLASS_PARTIAL_SPECIALIZATION */
template <class _Tp, class _Distance>
inline input_iterator_tag
iterator_category(const input_iterator<_Tp, _Distance>&)
{ return input_iterator_tag(); }
inline output_iterator_tag iterator_category(const output_iterator&)
{ return output_iterator_tag(); }
template <class _Tp, class _Distance>
inline forward_iterator_tag
iterator_category(const forward_iterator<_Tp, _Distance>&)
{ return forward_iterator_tag(); }
template <class _Tp, class _Distance>
inline bidirectional_iterator_tag
iterator_category(const bidirectional_iterator<_Tp, _Distance>&)
{ return bidirectional_iterator_tag(); }
template <class _Tp, class _Distance>
inline random_access_iterator_tag
iterator_category(const random_access_iterator<_Tp, _Distance>&)
{ return random_access_iterator_tag(); }
template <class _Tp>
inline random_access_iterator_tag iterator_category(const _Tp*)
{ return random_access_iterator_tag(); }
template <class _Tp, class _Distance>
inline _Tp* value_type(const input_iterator<_Tp, _Distance>&)
{ return (_Tp*)(0); }
template <class _Tp, class _Distance>
inline _Tp* value_type(const forward_iterator<_Tp, _Distance>&)
{ return (_Tp*)(0); }
template <class _Tp, class _Distance>
inline _Tp* value_type(const bidirectional_iterator<_Tp, _Distance>&)
{ return (_Tp*)(0); }
template <class _Tp, class _Distance>
inline _Tp* value_type(const random_access_iterator<_Tp, _Distance>&)
{ return (_Tp*)(0); }
template <class _Tp>
inline _Tp* value_type(const _Tp*) { return (_Tp*)(0); }
template <class _Tp, class _Distance>
inline _Distance* distance_type(const input_iterator<_Tp, _Distance>&)
{
return (_Distance*)(0);
}
template <class _Tp, class _Distance>
inline _Distance* distance_type(const forward_iterator<_Tp, _Distance>&)
{
return (_Distance*)(0);
}
template <class _Tp, class _Distance>
inline _Distance*
distance_type(const bidirectional_iterator<_Tp, _Distance>&)
{
return (_Distance*)(0);
}
template <class _Tp, class _Distance>
inline _Distance*
distance_type(const random_access_iterator<_Tp, _Distance>&)
{
return (_Distance*)(0);
}
template <class _Tp>
inline ptrdiff_t* distance_type(const _Tp*) { return (ptrdiff_t*)(0); }
// Without partial specialization we can't use iterator_traits, so
// we must keep the old iterator query functions around.
#define __ITERATOR_CATEGORY(__i) iterator_category(__i)
#define __DISTANCE_TYPE(__i) distance_type(__i)
#define __VALUE_TYPE(__i) value_type(__i)
#endif /* __STL_CLASS_PARTIAL_SPECIALIZATION */
template <class _InputIterator, class _Distance>
inline void __distance(_InputIterator __first, _InputIterator __last,
_Distance& __n, input_iterator_tag)
{
while (__first != __last) { ++__first; ++__n; }
}
template <class _RandomAccessIterator, class _Distance>
inline void __distance(_RandomAccessIterator __first,
_RandomAccessIterator __last,
_Distance& __n, random_access_iterator_tag)
{
__n += __last - __first;
}
template <class _InputIterator, class _Distance>
inline void distance(_InputIterator __first,
_InputIterator __last, _Distance& __n)
{
__distance(__first, __last, __n, iterator_category(__first));
}
#ifdef __STL_CLASS_PARTIAL_SPECIALIZATION
template <class _InputIterator>
inline typename iterator_traits<_InputIterator>::difference_type
__distance(_InputIterator __first, _InputIterator __last, input_iterator_tag)
{
typename iterator_traits<_InputIterator>::difference_type __n = 0;
while (__first != __last) {
++__first; ++__n;
}
return __n;
}
template <class _RandomAccessIterator>
inline typename iterator_traits<_RandomAccessIterator>::difference_type
__distance(_RandomAccessIterator __first, _RandomAccessIterator __last,
random_access_iterator_tag) {
return __last - __first;
}
template <class _InputIterator>
inline typename iterator_traits<_InputIterator>::difference_type
distance(_InputIterator __first, _InputIterator __last) {
typedef typename iterator_traits<_InputIterator>::iterator_category
_Category;
return __distance(__first, __last, _Category());
}
#endif /* __STL_CLASS_PARTIAL_SPECIALIZATION */
template <class _InputIter, class _Distance>
inline void __advance(_InputIter& __i, _Distance __n, input_iterator_tag) {
while (__n--) ++__i;
}
#if defined(__sgi) && !defined(__GNUC__) && (_MIPS_SIM != _MIPS_SIM_ABI32)
#pragma set woff 1183
#endif
template <class _BidirectionalIterator, class _Distance>
inline void __advance(_BidirectionalIterator& __i, _Distance __n,
bidirectional_iterator_tag) {
if (__n >= 0)
while (__n--) ++__i;
else
while (__n++) --__i;
}
#if defined(__sgi) && !defined(__GNUC__) && (_MIPS_SIM != _MIPS_SIM_ABI32)
#pragma reset woff 1183
#endif
template <class _RandomAccessIterator, class _Distance>
inline void __advance(_RandomAccessIterator& __i, _Distance __n,
random_access_iterator_tag) {
__i += __n;
}
template <class _InputIterator, class _Distance>
inline void advance(_InputIterator& __i, _Distance __n) {
__advance(__i, __n, iterator_category(__i));
}
__STL_END_NAMESPACE
#endif /* __SGI_STL_INTERNAL_ITERATOR_BASE_H */
// Local Variables:
// mode:C++
// End: