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Index: transform_iterator_ref.rst
===================================================================
RCS file: /cvsroot/boost/boost/libs/iterator/doc/transform_iterator_ref.rst,v
retrieving revision 1.3
retrieving revision 1.15
diff -w -d -u -b -r1.3 -r1.15
--- transform_iterator_ref.rst 21 Sep 2003 11:13:46 -0000 1.3
+++ transform_iterator_ref.rst 15 Jan 2004 00:06:57 -0000 1.15
@@ -1,3 +1,5 @@
+.. Version 1.3 of this document was accepted for TR1
+
::
template <class UnaryFunction,
@@ -5,26 +7,55 @@
class Reference = use_default,
class Value = use_default>
class transform_iterator
Issue 9.37x
- : public iterator_adaptor</* see discussion */>
{
- friend class iterator_core_access;
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);
Issue 9.43x
- template<class OtherIterator, class R2, class V2>
+ template<class F2, class I2, class R2, class V2>
transform_iterator(
- transform_iterator<UnaryFunction, OtherIterator, R2, V2> const& t
- , typename enable_if_convertible<OtherIterator, Iterator>::type* = 0 // exposition
+ transform_iterator<F2, I2, R2, V2> const& t
+ , typename enable_if_convertible<I2, Iterator>::type* = 0 // exposition only
+ , typename enable_if_convertible<F2, UnaryFunction>::type* = 0 // exposition only
);
-
Issues 9.37x and 9.12
+ Iterator const& base() const;
+ reference operator*() const;
+ transform_iterator& operator++();
+ transform_iterator& operator--();
private:
- typename transform_iterator::value_type dereference() const;
- UnaryFunction m_f;
+ Iterator m_iterator; // exposition only
+ UnaryFunction m_f; // exposition only
};
Issue 9.41x
+If ``Reference`` is ``use_default`` then the ``reference`` member of
+``transform_iterator`` is
+``result_of<UnaryFunction(iterator_traits<Iterator>::reference)>::type``.
+Otherwise, ``reference`` is ``Reference``.
+
+If ``Value`` is ``use_default`` then the ``value_type`` member is
+``remove_cv<remove_reference<reference> >::type``. Otherwise,
+``value_type`` is ``Value``.
+
+
Issue 9.37x
+If ``Iterator`` models Readable Lvalue Iterator and if ``Iterator``
+models Random Access Traversal Iterator, then ``iterator_category`` is
+convertible to ``random_access_iterator_tag``. Otherwise, if
+``Iterator`` models Bidirectional Traversal Iterator, then
+``iterator_category`` is convertible to
+``bidirectional_iterator_tag``. Otherwise ``iterator_category`` is
+convertible to ``forward_iterator_tag``. If ``Iterator`` does not
+model Readable Lvalue Iterator then ``iterator_category`` is
+convertible to ``input_iterator_tag``.
+
+
``transform_iterator`` requirements
...................................
@@ -34,27 +65,55 @@
where the type of ``f(*i)`` must be
``result_of<UnaryFunction(iterator_traits<Iterator>::reference)>::type``.
Issue 9.37x
-The type ``Iterator`` must at least model Readable Iterator. The
-resulting ``transform_iterator`` models the most refined of the
+The argument ``Iterator`` shall model Readable Iterator.
+
+
+``transform_iterator`` models
+.............................
+
+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.
Issue 9.41x
-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``.
Issue 9.37x.
+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.
-``transform_iterator`` public operations
-........................................
++-----------------------------------+---------------------------------+
+| 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<F1, X, R1, V1>`` is interoperable with
+``transform_iterator<F2, Y, R2, V2>`` if and only if ``X`` is
+interoperable with ``Y``.
+
+
+
+``transform_iterator`` operations
+.................................
+
+In addition to the operations required by the concepts modeled by
+``transform_iterator``, ``transform_iterator`` provides the following
+operations.
``transform_iterator();``
@@ -80,14 +139,30 @@
:Returns: An instance of ``transform_iterator`` that is a copy of ``t``.
:Requires: ``OtherIterator`` is implicitly convertible to ``Iterator``.
+
+``Iterator const& base() const;``
+
+:Returns: ``m_iterator``
+
+
``UnaryFunction functor() const;``
:Returns: ``m_f``
-``transform_iterator`` private operations
-.........................................
-``typename transform_iterator::value_type dereference() const;``
+``reference operator*() const;``
-:Returns: ``m_f(transform_iterator::dereference());``
+:Returns: ``m_f(*m_iterator)``
+
+
+``transform_iterator& operator++();``
+
+:Effects: ``++m_iterator``
+:Returns: ``*this``
+
+
+``transform_iterator& operator--();``
+
+:Effects: ``--m_iterator``
+:Returns: ``*this``
|
