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removed inheritance, specified member types explicitly

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[SVN r21471]
This commit is contained in:
Jeremy Siek
2004-01-04 04:29:50 +00:00
parent f0248daa1e
commit 5cc31f6539
1 changed files with 60 additions and 40 deletions
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100
doc/indirect_iterator_ref.rst
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@ -8,17 +8,14 @@
, class Difference = use_default
>
class indirect_iterator
: public iterator_adaptor<
indirect_iterator<Iterator, Value, Access, Traversal,
Reference, Difference>,
Iterator,
/* Value = see below */,
CategoryOrTraversal,
Reference,
Difference>
{
friend class iterator_core_access;
public:
typedef /* see below */ value_type;
typedef /* see below */ reference;
typedef /* see below */ pointer;
typedef /* see below */ difference_type;
typedef /* see below */ iterator_category;
indirect_iterator();
indirect_iterator(Iterator x);
@ -32,39 +29,62 @@
> const& y
, typename enable_if_convertible<Iterator2, Iterator>::type* = 0 // exposition
);
private: // as-if specification
typename indirect_iterator::reference dereference() const
{
return **this->base();
}
};
template <class Dereferenceable>
struct referent {
typedef /* see below */ type;
/* see below */
};
If ``Value`` is not ``use_default`` then the the argument for the
``iterator_adaptor`` base class' ``Value`` parameter is ``Value`` with
cv-qualifiers removed. If ``Value`` is ``use_default``, then the
argument for the ``iterator_adaptor`` base class' ``Value`` parameter
is computed as follows. We use the abbreviation
The member types of ``indirect_iterator`` are defined according to the
following pseudo-code. We use the abbreviation
``V=iterator_traits<Iterator>::value_type`` and ``v`` is an object of
type ``V``.::
if (*v returns a constant lvalue or an rvalue) then
referent<V>::type
else
add_const<referent<V>::type>::type
if (Value is use_default) then
if (referent<V> has member type) then
typedef remove_const<referent<V>::type> value_type;
else
typedef iterator_traits<V>::value_type value_type;
else
typedef remove_const<Value>::type value_type;
The algorithm for the ``type`` member of ``referent`` traits class is
as follows::
if (Reference is use_default) then
if (Value is use_default) then
if (referent<V> has member type) then
typedef referent<V>::type& reference;
else
typedef iterator_traits<V>::value_type& reference;
else
typedef Value& reference;
else
typedef Reference reference;
if (Dereferenceable is a class and has member element_type)
Dereferenceable::element_type
else
iterator_traits<Dereferenceable>::value_type
if (Value is use_default) then
if (referent<V> has member type) then
typedef referent<V>::type* pointer;
else
typedef iterator_traits<V>::value_type* pointer;
else
typedef Value* pointer;
if (Difference is use_default)
typedef iterator_traits<Iterator>::difference_type difference_type;
else
typedef Difference difference_type;
The member ``indirect_iterator::iterator_category`` is a type that
satisfies the requirements of the concepts modeled by the indirect
iterator as specified in the following requirements section.
(Should replace this with detailed description. -JGS)
If the ``Dereferenceable`` template argument to ``referent`` is a
class and has member ``element_type`` then ``referent``
contains the following typedef::
typedef Dereferenceable::element_type type;
``indirect_iterator`` requirements
@ -72,23 +92,23 @@ as follows::
The ``CategoryOrTraversal`` argument shall be one of the standard
iterator tags or ``use_default``. If ``CategoryOrTraversal`` is an
iterator tag, ``indirect_iterator`` satisfies the requirements
corresponding to the iterator tag. The template parameter
``Iterator`` argument shall meet the traversal requirements
corresponding to the iterator tag and the requirements of Readable
Iterator. If ``CategoryOrTraversal`` is ``use_default`` then
iterator tag, the template parameter ``Iterator`` argument shall meet
the traversal requirements corresponding to the iterator tag and the
requirements of Readable Iterator and ``indirect_iterator`` satisfies
the requirements corresponding to the iterator tag. If
``CategoryOrTraversal`` is ``use_default`` then the ``Iterator``
argument shall meet the requirements of Readable Iterator and
``indirect_iterator`` satisfies the requirements of the most refined
standard traversal concept that is satisfied by the ``Iterator``
argument. In this case the ``Iterator`` argument shall meet the
requirements of Readable Iterator.
argument. In this case
The expression ``*v``, where ``v`` is an object of type
``iterator_traits<Iterator>::value_type``, must be a valid expression
and must be convertible to ``iterator_adaptor::reference`` Also, there
are further requirements on the
and must be convertible to ``iterator_adaptor::reference``. Also,
there are further requirements on the
``iterator_traits<Iterator>::value_type`` if the ``Value`` parameter
is not ``use_default``, as implied by the algorithm for deducing the
default.
default for the ``value_type`` member.