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improved the models section of transform iterator to discuss old iterator

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[SVN r21643]
This commit is contained in:
Jeremy Siek
2004-01-12 20:18:41 +00:00
parent 436f7411f8
commit bcc0e80439
3 changed files with 130 additions and 27 deletions
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45
doc/transform_iterator_ref.rst
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@ -9,6 +9,12 @@
class transform_iterator
{
public:
typedef /* see below */ value_type;
typedef /* see below */ reference;
typedef /* see below */ pointer;
typedef iterator_traits<Iterator>::difference_type difference_type;
typedef /* see below */ iterator_category;
transform_iterator();
transform_iterator(Iterator const& x, UnaryFunction f);
@ -29,6 +35,14 @@
};
The ``reference`` type of ``transform_iterator`` is
``result_of<UnaryFunction(iterator_traits<Iterator>::reference)>::type``.
The ``value_type`` is ``remove_cv<remove_reference<reference> >::type``.
The ``iterator_category`` member is a type convertible to the tags
corresponding to each standard concept modeled by
``transform_iterator``, as described in the models section.
``transform_iterator`` requirements
...................................
@ -38,7 +52,7 @@ type ``UnaryFunction``, ``i`` is an object of type ``Iterator``, and
where the type of ``f(*i)`` must be
``result_of<UnaryFunction(iterator_traits<Iterator>::reference)>::type``.
The type ``Iterator`` must at least model Readable Iterator.
The argument ``Iterator`` shall model Readable Iterator.
``transform_iterator`` models
@ -47,20 +61,33 @@ The type ``Iterator`` must at least model Readable Iterator.
The resulting ``transform_iterator`` models the most refined of the
following options that is also modeled by ``Iterator``.
* Writable Lvalue Iterator if ``result_of<UnaryFunction(iterator_traits<Iterator>::reference)>::type`` is a non-const reference.
* Writable Lvalue Iterator if ``transform_iterator::reference`` is a non-const reference.
* Readable Lvalue Iterator if ``result_of<UnaryFunction(iterator_traits<Iterator>::reference)>::type`` is a const
reference.
* Readable Lvalue Iterator if ``transform_iterator::reference`` is a const reference.
* Readable Iterator otherwise.
The ``transform_iterator`` models the most refined standard traversal
concept that is modeled by ``Iterator``.
concept that is modeled by the ``Iterator`` argument.
The ``reference`` type of ``transform_iterator`` is
``result_of<UnaryFunction(iterator_traits<Iterator>::reference)>::type``.
The ``value_type`` is ``remove_cv<remove_reference<reference> >::type``.
If ``transform_iterator`` is a model of Readable Lvalue Iterator then
it models the following original iterator concepts depending on what
the ``Iterator`` argument models.
+-----------------------------------+---------------------------------+
| If ``Iterator`` models | then ``filter_iterator`` models |
+===================================+=================================+
| Single Pass Iterator | Input Iterator |
+-----------------------------------+---------------------------------+
| Forward Traversal Iterator | Forward Iterator |
+-----------------------------------+---------------------------------+
| Bidirectional Traversal Iterator | Bidirectional Iterator |
+-----------------------------------+---------------------------------+
| Random Access Traversal Iterator | Random Access Iterator |
+-----------------------------------+---------------------------------+
If ``transform_iterator`` models Writable Lvalue Iterator then it is a
mutable iterator (as defined in the old iterator requirements).
``transform_iterator`` operations