feedc0de/boost_iterator
1
0
Fork 0
forked from boostorg/iterator
Code Pull Requests Activity

Added iterator_traits_adaptor.

Browse Source 
Implemented minimum_category.
Removed base class injection facilities.


[SVN r879]
This commit is contained in:
Thomas Witt
2003-01-27 20:41:09 +00:00
parent 7818686c94
commit 4e63c5e8dc
4 changed files with 243 additions and 75 deletions
Download Patch File Download Diff File Expand all files Collapse all files
include/boost/iterator/detail/categories.hpp
+99 -14
View File
@@ -12,7 +12,6 @@
#include <boost/type_traits/conversion_traits.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/bool_c.hpp>
#include <boost/mpl/logical/or.hpp>
#include <iterator>
#if BOOST_WORKAROUND(__MWERKS__, <=0x2407)
@@ -21,6 +20,13 @@
namespace boost {
//
// Categories
//
// !! Fix detection functions if categories
// are changed.
//
// Return Type Categories
struct readable_iterator_tag { };
struct writable_iterator_tag { };
@@ -199,16 +205,39 @@ namespace boost {
//
// Return type
//
// The nested is_category template class are used for
// minimum category detection in iterator_adaptors.
// They are basically a pore mans is_derived replacement.
//
// A implementation may look like this
//
// template <class Cat1, class Cat2>
// struct min_cat
// : mpl::if_< is_return_category< Cat1 >::template is_category< Cat2 >,
// Cat1,
// mpl::if_< is_return_category<Cat2>::template is_category<Cat1>,
// Cat2,
// error_type
// >
// > {};
template <class Category>
struct is_mutable_lvalue_iterator :
mpl::false_c
{};
{
template <class T>
struct is_category
: boost::mpl::false_c {};
};
template <>
struct is_mutable_lvalue_iterator<mutable_lvalue_iterator_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_mutable_lvalue_iterator<Category> {};
};
template <class Category>
struct is_constant_lvalue_iterator :
@@ -218,7 +247,11 @@ namespace boost {
template <>
struct is_constant_lvalue_iterator<constant_lvalue_iterator_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_constant_lvalue_iterator<Category> {};
};
template <class Category>
struct is_swappable_iterator :
@@ -228,18 +261,27 @@ namespace boost {
template <>
struct is_swappable_iterator<swappable_iterator_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_swappable_iterator<Category> {};
};
template <class Category>
struct is_readable_iterator :
mpl::logical_or< is_swappable_iterator<Category>,
is_constant_lvalue_iterator<Category> >
mpl::if_< is_swappable_iterator<Category>,
is_swappable_iterator<Category>,
is_constant_lvalue_iterator<Category> >::type
{};
template <>
struct is_readable_iterator<readable_iterator_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_readable_iterator<Category> {};
};
template <class Category>
struct is_writable_iterator :
@@ -249,7 +291,19 @@ namespace boost {
template <>
struct is_writable_iterator<writable_iterator_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_writable_iterator<Category> {};
};
template <class Category>
struct is_return_category
: mpl::if_< is_writable_iterator<Category>,
is_writable_iterator<Category>,
is_readable_iterator<Category> >::type
{
};
//
// Traversal
@@ -258,12 +312,20 @@ namespace boost {
template <class Category>
struct is_random_access_traversal_iterator :
mpl::false_c
{};
{
template <class T>
struct is_category
: boost::mpl::false_c {};
};
template <>
struct is_random_access_traversal_iterator<random_access_traversal_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_random_access_traversal_iterator<Category> {};
};
template <class Category>
struct is_bidirectional_traversal_iterator :
@@ -273,7 +335,11 @@ namespace boost {
template <>
struct is_bidirectional_traversal_iterator<bidirectional_traversal_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_bidirectional_traversal_iterator<Category> {};
};
template <class Category>
struct is_forward_traversal_iterator :
@@ -283,7 +349,11 @@ namespace boost {
template <>
struct is_forward_traversal_iterator<forward_traversal_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_forward_traversal_iterator<Category> {};
};
template <class Category>
struct is_input_traversal_iterator :
@@ -293,7 +363,11 @@ namespace boost {
template <>
struct is_input_traversal_iterator<input_traversal_tag> :
mpl::true_c
{};
{
template <class Category>
struct is_category
: is_input_traversal_iterator<Category> {};
};
template <class Category>
struct is_output_traversal_iterator :
@@ -303,6 +377,17 @@ namespace boost {
template <>
struct is_output_traversal_iterator<output_traversal_tag> :
mpl::true_c
{
template <class Category>
struct is_category
: is_output_traversal_iterator<Category> {};
};
template <class Category>
struct is_traversal_category
: mpl::if_< is_input_traversal_iterator<Category>,
is_input_traversal_iterator<Category>,
is_output_traversal_iterator<Category> >::type
{};
#endif