template <
    class Iterator
  , class Value = use_default
  , class CategoryOrTraversal = use_default
  , class Reference = use_default
  , class Difference = use_default
>
class indirect_iterator
{
 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);

    template <
        class Iterator2, class Value2, class Category2
      , class Reference2, class Difference2
    >
    indirect_iterator(
        indirect_iterator<
             Iterator2, Value2, Category2, Reference2, Difference2
        > const& y
      , typename enable_if_convertible<Iterator2, Iterator>::type* = 0 // exposition
    );

    Iterator const& base() const;
    reference operator*() const;
    indirect_iterator& operator++();
    indirect_iterator& operator--();
private:
   Iterator m_iterator; // exposition
};

The member types of indirect_iterator are defined according to the following pseudo-code, where V is iterator_traits<Iterator>::value_type

if (Value is use_default) then
    typedef remove_const<pointee<V>::type>::type value_type;
else
    typedef remove_const<Value>::type value_type;

if (Reference is use_default) then
    if (Value is use_default) then
        typedef indirect_reference<V>::type reference;
    else
        typedef Value& reference;
else
    typedef Reference reference;

if (Value is use_default) then 
    typedef pointee<V>::type* pointer;
else 
    typedef Value* pointer;

if (Difference is use_default)
    typedef iterator_traits<Iterator>::difference_type difference_type;
else
    typedef Difference difference_type;

if (CategoryOrTraversal is use_default)
    typedef iterator-category (
        iterator_traversal<Iterator>::type,``reference``,``value_type``
    ) iterator_category;
else
    typedef iterator-category (
        CategoryOrTraversal,``reference``,``value_type``
    ) iterator_category;

`indirect_iterator` requirements

The expression *v, where v is an object of iterator_traits<Iterator>::value_type, shall be valid expression and convertible to reference. Iterator shall model the traversal concept indicated by iterator_category. Value, Reference, and Difference shall be chosen so that value_type, reference, and difference_type meet the requirements indicated by iterator_category.

[Note: 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 for the value_type member.]

`indirect_iterator` models

In addition to the concepts indicated by iterator_category and by iterator_traversal<indirect_iterator>::type, a specialization of indirect_iterator models the following concepts, Where v is an object of iterator_traits<Iterator>::value_type:

Readable Iterator if reference(*v) is convertible to value_type.

Writable Iterator if reference(*v) = t is a valid expression (where t is an object of type indirect_iterator::value_type)

Lvalue Iterator if reference is a reference type.

indirect_iterator<X,V1,C1,R1,D1> is interoperable with indirect_iterator<Y,V2,C2,R2,D2> if and only if X is interoperable with Y.

`indirect_iterator` operations

In addition to the operations required by the concepts described above, specializations of indirect_iterator provide the following operations.

indirect_iterator();

Requires:	`Iterator` must be Default Constructible.
Effects:	Constructs an instance of `indirect_iterator` with a default-constructed `m_iterator`.

indirect_iterator(Iterator x);

Effects:	Constructs an instance of `indirect_iterator` with `m_iterator` copy constructed from `x`.

template <
    class Iterator2, class Value2, unsigned Access, class Traversal
  , class Reference2, class Difference2
>
indirect_iterator(
    indirect_iterator<
         Iterator2, Value2, Access, Traversal, Reference2, Difference2
    > const& y
  , typename enable_if_convertible<Iterator2, Iterator>::type* = 0 // exposition
);

Requires:	`Iterator2` is implicitly convertible to `Iterator`.
Effects:	Constructs an instance of `indirect_iterator` whose `m_iterator` subobject is constructed from `y.base()`.

Iterator const& base() const;

Returns:	`m_iterator`

reference operator*() const;

Returns:	`**m_iterator`

indirect_iterator& operator++();

Effects:	`++m_iterator`
Returns:	`*this`

indirect_iterator& operator--();

Effects:	`--m_iterator`
Returns:	`*this`

indirect_iterator requirements

indirect_iterator models

indirect_iterator operations

`indirect_iterator` requirements

`indirect_iterator` models

`indirect_iterator` operations