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Separate access and traversal for iterator_adaptor

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[SVN r20162]
This commit is contained in:
Dave Abrahams
2003-09-22 19:55:01 +00:00
parent 50fe1b062b
commit ebb09db44e
12 changed files with 485 additions and 170 deletions
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85
doc/iterator_adaptor_ref.rst
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@ -1,10 +1,12 @@
.. parsed-literal::
bool
template <
class Derived
, class Base
, class Value = use_default
, class Category = use_default
, unsigned Access = use_default_access
, class Traversal = use_default
, class Reference = use_default
, class Difference = use_default
>
@ -60,55 +62,46 @@ traits types for ``iterator_adaptor``.
::
if (Value == use_default)
value_type = iterator_traits<Base>::value_type;
else
if (Value != use_default)
value_type = remove_cv<Value>::type;
if (Reference == use_default) {
if (Value == use_default)
reference = iterator_traits<Base>::reference;
else
reference = Value&;
} else
reference = Reference;
if (Distance == use_default)
difference_type = iterator_traits<Base>::difference_type;
else
difference_type = Distance;
if (Category == use_default)
iterator_category = iterator_tag<
access_category< Base >,
traversal_category< Base >
>
else if (Category is convertible to a standard access tag)
iterator_category = iterator_tag<
Category
else if (Category has a nested traversal type)
if (reference is not a reference-to-const)
Category::access
else
if (Category
else if (Category is convertable to a standard traversal tag)
...
else
iterator_category = Category;
// Actually the above is wrong. See the use of
// access_category_tag and
// new_category_to_access/iter_category_to_access.
else
value_type = iterator_traits<Base>::value_type;
.. Replaced with new semantics --thw
if (Category == use_default)
iterator_category = iterator_traits<Base>::iterator_category;
else
iterator_category = Category;
if (Traversal != use_default)
traversal_category = Traversal
else
traversal_category = traversal_category< Base >::type
Fix this up!!
iterator_category = iterator_tag<
access_category
, traversal_category
>
if (Access != use_default)
{
access_category = Access
}
else
{
access_category
= access_category< Base >::value
if (is_const<Value>)
access_category &= ~writable_iterator;
}
iterator_category = iterator_tag<
access_category
, traversal_category
>
if (Reference != use_default)
reference = Reference
else if (Value != use_default)
reference = Value&
else
reference = iterator_traits<Base>::reference
``iterator_adaptor`` public operations