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Cleaned up flotsam and jetsam, simplified

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[SVN r795]
This commit is contained in:
Dave Abrahams
2002-12-26 00:22:34 +00:00
parent 751d4831ef
commit 962677e305
1 changed files with 92 additions and 144 deletions
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236
include/boost/iterator/iterator_categories.hpp
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@@ -13,12 +13,13 @@
#include <boost/config.hpp> #include <boost/config.hpp>
#include <boost/type_traits/conversion_traits.hpp> #include <boost/type_traits/conversion_traits.hpp>
#include <boost/type_traits/cv_traits.hpp> #include <boost/type_traits/cv_traits.hpp>
#include <boost/pending/ct_if.hpp>
#include <boost/detail/iterator.hpp> #include <boost/detail/iterator.hpp>
#include <boost/mpl/apply_if.hpp> #include <boost/mpl/apply_if.hpp>
#include <boost/mpl/if.hpp> #include <boost/mpl/if.hpp>
#include <boost/mpl/bool_c.hpp> #include <boost/mpl/bool_c.hpp>
#include <boost/mpl/aux_/has_xxx.hpp> #include <boost/mpl/aux_/has_xxx.hpp>
#include <boost/mpl/logical/or.hpp>
#include <boost/mpl/logical/and.hpp>
#include <iterator> #include <iterator>
namespace boost { namespace boost {
@@ -68,107 +69,59 @@ namespace boost {
// traversal_category. // traversal_category.
struct new_iterator_base { }; struct new_iterator_base { };
namespace detail { namespace detail
{
struct return_category_from_nested_type {
template <typename Iterator> struct bind {
typedef typename Iterator::return_category type;
};
};
struct traversal_category_from_nested_type {
template <typename Iterator> struct bind {
typedef typename Iterator::traversal_category type;
};
};
template <typename ValueType> template <typename ValueType>
struct choose_lvalue_return { struct choose_lvalue_return
typedef typename ct_if<is_const<ValueType>::value, : mpl::if_<
boost::constant_lvalue_iterator_tag, is_const<ValueType>
boost::mutable_lvalue_iterator_tag>::type type; , boost::constant_lvalue_iterator_tag
, boost::mutable_lvalue_iterator_tag>
{
}; };
template <typename Category, typename ValueType> template <typename Category, typename ValueType>
struct iter_category_to_return { struct iter_category_to_return
typedef typename ct_if< : mpl::if_<
is_convertible<Category*, std::forward_iterator_tag*>::value, is_convertible<Category*, std::forward_iterator_tag*>
typename choose_lvalue_return<ValueType>::type, , typename choose_lvalue_return<ValueType>::type
typename ct_if< , typename mpl::if_<
is_convertible<Category*, std::input_iterator_tag*>::value, is_convertible<Category*, std::input_iterator_tag*>
boost::readable_iterator_tag, , boost::readable_iterator_tag
typename ct_if< , typename mpl::if_<
is_convertible<Category*, std::output_iterator_tag*>::value, is_convertible<Category*, std::output_iterator_tag*>
boost::writable_iterator_tag, , boost::writable_iterator_tag
boost::error_iterator_tag , boost::error_iterator_tag
>::type >::type
>::type >::type
>::type type; >
{
}; };
template <typename Category> template <typename Category>
struct iter_category_to_traversal { struct iter_category_to_traversal
typedef typename ct_if< : mpl::if_<
is_convertible<Category*, std::random_access_iterator_tag*>::value, is_convertible<Category*, std::random_access_iterator_tag*>
random_access_traversal_tag, , random_access_traversal_tag
typename ct_if< , typename mpl::if_<
is_convertible<Category*, std::bidirectional_iterator_tag*>::value, is_convertible<Category*, std::bidirectional_iterator_tag*>
bidirectional_traversal_tag, , bidirectional_traversal_tag
typename ct_if< , typename mpl::if_<
is_convertible<Category*, std::forward_iterator_tag*>::value, is_convertible<Category*, std::forward_iterator_tag*>
forward_traversal_tag, , forward_traversal_tag
typename ct_if< , typename mpl::if_<
is_convertible<Category*, std::input_iterator_tag*>::value, is_convertible<Category*, std::input_iterator_tag*>
input_traversal_tag, , input_traversal_tag
output_traversal_tag , output_traversal_tag
>::type >::type
>::type
>::type >::type
>::type >
>::type type; {
}; };
#if 0
struct return_category_from_old_traits {
template <typename Iterator> class bind {
typedef boost::detail::iterator_traits<Iterator> OldTraits;
typedef typename OldTraits::iterator_category Cat;
typedef typename OldTraits::value_type value_type;
public:
typedef typename iter_category_to_return<Cat, value_type>::type type;
};
};
struct traversal_category_from_old_traits {
template <typename Iterator> class bind {
typedef boost::detail::iterator_traits<Iterator> OldTraits;
typedef typename OldTraits::iterator_category Cat;
public:
typedef typename iter_category_to_traversal<Cat>::type type;
};
};
template <typename Iterator>
class choose_return_category {
typedef typename ct_if<is_convertible<Iterator*,
new_iterator_base*>::value,
return_category_from_nested_type,
return_category_from_old_traits>::type Choice;
public:
typedef typename Choice:: template bind<Iterator>::type type;
};
template <typename Iterator>
class choose_traversal_category {
typedef typename ct_if<is_convertible<Iterator*,
new_iterator_base*>::value,
traversal_category_from_nested_type,
traversal_category_from_old_traits>::type Choice;
public:
typedef typename Choice:: template bind<Iterator>::type type;
};
#else
BOOST_MPL_HAS_XXX_TRAIT_DEF(traversal) BOOST_MPL_HAS_XXX_TRAIT_DEF(traversal)
template <class Tag> template <class Tag>
@@ -180,23 +133,8 @@ namespace boost {
, mpl::bool_c<false> >::type , mpl::bool_c<false> >::type
{ {
}; };
#endif
} // namespace detail } // namespace detail
#if 0
template <class Iterator>
struct return_category {
typedef typename detail::choose_return_category<Iterator>::type type;
};
template <class Iterator>
struct traversal_category {
typedef typename detail::choose_traversal_category<Iterator>::type type;
};
#else
namespace detail { namespace detail {
template <class NewCategoryTag> template <class NewCategoryTag>
@@ -231,28 +169,29 @@ namespace boost {
} // namespace detail } // namespace detail
template <class Iterator> template <class Iterator>
struct return_category { struct return_category
typedef typename detail::return_category_tag< : detail::return_category_tag<
typename detail::iterator_traits<Iterator>::iterator_category typename detail::iterator_traits<Iterator>::iterator_category
, typename detail::iterator_traits<Iterator>::value_type>::type type; , typename detail::iterator_traits<Iterator>::value_type>
}; {};
template <class Iterator> template <class Iterator>
struct traversal_category { struct traversal_category
typedef typename detail::traversal_category_tag< : detail::traversal_category_tag<
typename detail::iterator_traits<Iterator>::iterator_category typename detail::iterator_traits<Iterator>::iterator_category
, typename detail::iterator_traits<Iterator>::value_type>::type type; , typename detail::iterator_traits<Iterator>::value_type>
{
}; };
#endif
#if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
template <typename T> template <typename T>
struct return_category<T*> struct return_category<T*>
: mpl::if_<
is_const<T>
, constant_lvalue_iterator_tag
, mutable_lvalue_iterator_tag>
{ {
typedef typename ct_if<is_const<T>::value,
constant_lvalue_iterator_tag,
mutable_lvalue_iterator_tag>::type type;
}; };
template <typename T> template <typename T>
@@ -264,34 +203,43 @@ namespace boost {
#endif #endif
template <class RC, class TC> template <class RC, class TC>
struct cvt_iterator_category { struct cvt_iterator_category
typedef : mpl::if_<
typename mpl::if_c< mpl::logical_or<
(is_convertible<RC*, mutable_lvalue_iterator_tag*>::value || is_convertible<RC*, constant_lvalue_iterator_tag*>::value) is_convertible<RC*, mutable_lvalue_iterator_tag*>
, typename mpl::if_c< , is_convertible<RC*, constant_lvalue_iterator_tag*>
is_convertible<TC*, random_access_traversal_tag*>::value >
, std::random_access_iterator_tag , typename mpl::if_<
, typename mpl::if_< is_convertible<TC*, random_access_traversal_tag*>
is_convertible<TC*, bidirectional_traversal_tag*> , std::random_access_iterator_tag
, std::bidirectional_iterator_tag , typename mpl::if_<
, typename mpl::if_< is_convertible<TC*, bidirectional_traversal_tag*>
is_convertible<TC*, forward_traversal_tag*> , std::bidirectional_iterator_tag
, std::forward_iterator_tag , typename mpl::if_<
, error_iterator_tag is_convertible<TC*, forward_traversal_tag*>
, std::forward_iterator_tag
, error_iterator_tag
>::type
>::type >::type
>::type >::type
>::type,
typename mpl::if_c< , typename mpl::if_<
(is_convertible<RC*, readable_iterator_tag*>::value && is_convertible<TC*, input_traversal_tag*>::value) mpl::logical_and<
, std::input_iterator_tag is_convertible<RC*, readable_iterator_tag*>
, typename mpl::if_c< , is_convertible<TC*, input_traversal_tag*>
(is_convertible<RC*, writable_iterator_tag*>::value >
&& is_convertible<TC*, output_traversal_tag*>::value) , std::input_iterator_tag
, std::output_iterator_tag , typename mpl::if_<
, error_iterator_tag mpl::logical_and<
>::type is_convertible<RC*, writable_iterator_tag*>
>::type , is_convertible<TC*, output_traversal_tag*>
>::type type; >
, std::output_iterator_tag
, error_iterator_tag
>::type
>::type
>
{
}; };
template <class ReturnTag, class TraversalTag> template <class ReturnTag, class TraversalTag>