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added pseudo-code for facade_iterator_category type function

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[SVN r21736]
This commit is contained in:
Jeremy Siek committed 2004-01-14 19:57:11 +00:00
1 parent 731576fbfe
commit 2854c5c761
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doc/counting_iterator.html
+5 -4
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@@ -95,12 +95,13 @@ type. Otherwise <tt class="literal"><span class="pre">difference_type</span></tt
<p>If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is not <tt class="literal"><span class="pre">use_default</span></tt> then the member
<tt class="literal"><span class="pre">iterator_category</span></tt> is <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>. Otherwise, if
<tt class="literal"><span class="pre">numeric_limits&lt;Incrementable&gt;::is_specialized</span></tt>, then
<tt class="literal"><span class="pre">iterator_category</span></tt> is a type convertible to
<tt class="literal"><span class="pre">random_access_iterator_tag</span></tt>. Otherwise, <tt class="literal"><span class="pre">iterator_category</span></tt> is
unspecified.</p>
<tt class="literal"><span class="pre">iterator_category</span></tt> is a
<tt class="literal"><span class="pre">facade_iterator_category(random_access_traversal_tag,</span> <span class="pre">Incrementable,</span> <span class="pre">const</span> <span class="pre">Incrementable&amp;)</span></tt>.
Otherwise, <tt class="literal"><span class="pre">iterator_category</span></tt> is
<tt class="literal"><span class="pre">facade_iterator_category(iterator_traversal&lt;Incrementable&gt;::type,</span> <span class="pre">Incrementable,</span> <span class="pre">const</span> <span class="pre">Incrementable&amp;)</span></tt>.</p>
<dl>
<dt>[<em>Note:</em> implementers are encouraged to provide an implementation of</dt>
<dd><tt class="literal"><span class="pre">operator-</span></tt> and a <tt class="literal"><span class="pre">difference_type</span></tt> that avoids overflows in
<dd><tt class="literal"><span class="pre">operator-</span></tt> and the default <tt class="literal"><span class="pre">difference_type</span></tt> that avoids overflows in
the cases when the <tt class="literal"><span class="pre">Incrementable</span></tt> type is a numeric type.]</dd>
</dl>
</div>
doc/counting_iterator_ref.rst
+6 -4
View File
@@ -33,12 +33,14 @@ type. Otherwise ``difference_type`` is ``Difference``.
If ``CategoryOrTraversal`` is not ``use_default`` then the member
``iterator_category`` is ``CategoryOrTraversal``. Otherwise, if
``numeric_limits<Incrementable>::is_specialized``, then
``iterator_category`` is a type convertible to
``random_access_iterator_tag``. Otherwise, ``iterator_category`` is
unspecified.
``iterator_category`` is a
``facade_iterator_category(random_access_traversal_tag, Incrementable, const Incrementable&)``.
Otherwise, ``iterator_category`` is
``facade_iterator_category(iterator_traversal<Incrementable>::type, Incrementable, const Incrementable&)``.
[*Note:* implementers are encouraged to provide an implementation of
``operator-`` and a ``difference_type`` that avoids overflows in
``operator-`` and the default ``difference_type`` that avoids overflows in
the cases when the ``Incrementable`` type is a numeric type.]
``counting_iterator`` requirements
doc/facade-and-adaptor.html
+132 -206
View File
@@ -77,63 +77,62 @@ by adapting other iterators.</td>
<li><a class="reference" href="#iterator-facade-lib-iterator-facade" id="id27" name="id27">Iterator facade [lib.iterator.facade]</a><ul>
<li><a class="reference" href="#class-template-iterator-facade" id="id28" name="id28">Class template <tt class="literal"><span class="pre">iterator_facade</span></tt></a></li>
<li><a class="reference" href="#iterator-facade-requirements" id="id29" name="id29"><tt class="literal"><span class="pre">iterator_facade</span></tt> Requirements</a></li>
<li><a class="reference" href="#iterator-facade-iterator-category" id="id30" name="id30"><tt class="literal"><span class="pre">iterator_facade</span></tt> iterator category</a></li>
<li><a class="reference" href="#iterator-facade-operations" id="id31" name="id31"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></li>
<li><a class="reference" href="#iterator-facade-operations" id="id30" name="id30"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></li>
</ul>
</li>
<li><a class="reference" href="#iterator-adaptor-lib-iterator-adaptor" id="id32" name="id32">Iterator adaptor [lib.iterator.adaptor]</a><ul>
<li><a class="reference" href="#class-template-iterator-adaptor" id="id33" name="id33">Class template <tt class="literal"><span class="pre">iterator_adaptor</span></tt></a></li>
<li><a class="reference" href="#iterator-adaptor-requirements" id="id34" name="id34"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> requirements</a></li>
<li><a class="reference" href="#iterator-adaptor-base-class-parameters" id="id35" name="id35"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> base class parameters</a></li>
<li><a class="reference" href="#iterator-adaptor-models" id="id36" name="id36"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> models</a></li>
<li><a class="reference" href="#iterator-adaptor-public-operations" id="id37" name="id37"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> public operations</a></li>
<li><a class="reference" href="#iterator-adaptor-protected-member-functions" id="id38" name="id38"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> protected member functions</a></li>
<li><a class="reference" href="#iterator-adaptor-private-member-functions" id="id39" name="id39"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> private member functions</a></li>
<li><a class="reference" href="#iterator-adaptor-lib-iterator-adaptor" id="id31" name="id31">Iterator adaptor [lib.iterator.adaptor]</a><ul>
<li><a class="reference" href="#class-template-iterator-adaptor" id="id32" name="id32">Class template <tt class="literal"><span class="pre">iterator_adaptor</span></tt></a></li>
<li><a class="reference" href="#iterator-adaptor-requirements" id="id33" name="id33"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> requirements</a></li>
<li><a class="reference" href="#iterator-adaptor-base-class-parameters" id="id34" name="id34"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> base class parameters</a></li>
<li><a class="reference" href="#iterator-adaptor-models" id="id35" name="id35"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> models</a></li>
<li><a class="reference" href="#iterator-adaptor-public-operations" id="id36" name="id36"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> public operations</a></li>
<li><a class="reference" href="#iterator-adaptor-protected-member-functions" id="id37" name="id37"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> protected member functions</a></li>
<li><a class="reference" href="#iterator-adaptor-private-member-functions" id="id38" name="id38"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> private member functions</a></li>
</ul>
</li>
<li><a class="reference" href="#specialized-adaptors-lib-iterator-special-adaptors" id="id40" name="id40">Specialized adaptors [lib.iterator.special.adaptors]</a><ul>
<li><a class="reference" href="#indirect-iterator" id="id41" name="id41">Indirect iterator</a><ul>
<li><a class="reference" href="#class-template-pointee" id="id42" name="id42">Class template <tt class="literal"><span class="pre">pointee</span></tt></a></li>
<li><a class="reference" href="#class-template-indirect-reference" id="id43" name="id43">Class template <tt class="literal"><span class="pre">indirect_reference</span></tt></a></li>
<li><a class="reference" href="#class-template-indirect-iterator" id="id44" name="id44">Class template <tt class="literal"><span class="pre">indirect_iterator</span></tt></a></li>
<li><a class="reference" href="#indirect-iterator-requirements" id="id45" name="id45"><tt class="literal"><span class="pre">indirect_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#indirect-iterator-models" id="id46" name="id46"><tt class="literal"><span class="pre">indirect_iterator</span></tt> models</a></li>
<li><a class="reference" href="#indirect-iterator-operations" id="id47" name="id47"><tt class="literal"><span class="pre">indirect_iterator</span></tt> operations</a></li>
<li><a class="reference" href="#specialized-adaptors-lib-iterator-special-adaptors" id="id39" name="id39">Specialized adaptors [lib.iterator.special.adaptors]</a><ul>
<li><a class="reference" href="#indirect-iterator" id="id40" name="id40">Indirect iterator</a><ul>
<li><a class="reference" href="#class-template-pointee" id="id41" name="id41">Class template <tt class="literal"><span class="pre">pointee</span></tt></a></li>
<li><a class="reference" href="#class-template-indirect-reference" id="id42" name="id42">Class template <tt class="literal"><span class="pre">indirect_reference</span></tt></a></li>
<li><a class="reference" href="#class-template-indirect-iterator" id="id43" name="id43">Class template <tt class="literal"><span class="pre">indirect_iterator</span></tt></a></li>
<li><a class="reference" href="#indirect-iterator-requirements" id="id44" name="id44"><tt class="literal"><span class="pre">indirect_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#indirect-iterator-models" id="id45" name="id45"><tt class="literal"><span class="pre">indirect_iterator</span></tt> models</a></li>
<li><a class="reference" href="#indirect-iterator-operations" id="id46" name="id46"><tt class="literal"><span class="pre">indirect_iterator</span></tt> operations</a></li>
</ul>
</li>
<li><a class="reference" href="#reverse-iterator" id="id48" name="id48">Reverse iterator</a><ul>
<li><a class="reference" href="#class-template-reverse-iterator" id="id49" name="id49">Class template <tt class="literal"><span class="pre">reverse_iterator</span></tt></a></li>
<li><a class="reference" href="#reverse-iterator-requirements" id="id50" name="id50"><tt class="literal"><span class="pre">reverse_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#reverse-iterator-models" id="id51" name="id51"><tt class="literal"><span class="pre">reverse_iterator</span></tt> models</a></li>
<li><a class="reference" href="#reverse-iterator-operations" id="id52" name="id52"><tt class="literal"><span class="pre">reverse_iterator</span></tt> operations</a></li>
<li><a class="reference" href="#reverse-iterator" id="id47" name="id47">Reverse iterator</a><ul>
<li><a class="reference" href="#class-template-reverse-iterator" id="id48" name="id48">Class template <tt class="literal"><span class="pre">reverse_iterator</span></tt></a></li>
<li><a class="reference" href="#reverse-iterator-requirements" id="id49" name="id49"><tt class="literal"><span class="pre">reverse_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#reverse-iterator-models" id="id50" name="id50"><tt class="literal"><span class="pre">reverse_iterator</span></tt> models</a></li>
<li><a class="reference" href="#reverse-iterator-operations" id="id51" name="id51"><tt class="literal"><span class="pre">reverse_iterator</span></tt> operations</a></li>
</ul>
</li>
<li><a class="reference" href="#transform-iterator" id="id53" name="id53">Transform iterator</a><ul>
<li><a class="reference" href="#class-template-transform-iterator" id="id54" name="id54">Class template <tt class="literal"><span class="pre">transform_iterator</span></tt></a></li>
<li><a class="reference" href="#transform-iterator-requirements" id="id55" name="id55"><tt class="literal"><span class="pre">transform_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#transform-iterator-models" id="id56" name="id56"><tt class="literal"><span class="pre">transform_iterator</span></tt> models</a></li>
<li><a class="reference" href="#transform-iterator-operations" id="id57" name="id57"><tt class="literal"><span class="pre">transform_iterator</span></tt> operations</a></li>
<li><a class="reference" href="#transform-iterator" id="id52" name="id52">Transform iterator</a><ul>
<li><a class="reference" href="#class-template-transform-iterator" id="id53" name="id53">Class template <tt class="literal"><span class="pre">transform_iterator</span></tt></a></li>
<li><a class="reference" href="#transform-iterator-requirements" id="id54" name="id54"><tt class="literal"><span class="pre">transform_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#transform-iterator-models" id="id55" name="id55"><tt class="literal"><span class="pre">transform_iterator</span></tt> models</a></li>
<li><a class="reference" href="#transform-iterator-operations" id="id56" name="id56"><tt class="literal"><span class="pre">transform_iterator</span></tt> operations</a></li>
</ul>
</li>
<li><a class="reference" href="#filter-iterator" id="id58" name="id58">Filter iterator</a><ul>
<li><a class="reference" href="#class-template-filter-iterator" id="id59" name="id59">Class template <tt class="literal"><span class="pre">filter_iterator</span></tt></a></li>
<li><a class="reference" href="#filter-iterator-requirements" id="id60" name="id60"><tt class="literal"><span class="pre">filter_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#filter-iterator-models" id="id61" name="id61"><tt class="literal"><span class="pre">filter_iterator</span></tt> models</a></li>
<li><a class="reference" href="#filter-iterator-operations" id="id62" name="id62"><tt class="literal"><span class="pre">filter_iterator</span></tt> operations</a></li>
<li><a class="reference" href="#filter-iterator" id="id57" name="id57">Filter iterator</a><ul>
<li><a class="reference" href="#class-template-filter-iterator" id="id58" name="id58">Class template <tt class="literal"><span class="pre">filter_iterator</span></tt></a></li>
<li><a class="reference" href="#filter-iterator-requirements" id="id59" name="id59"><tt class="literal"><span class="pre">filter_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#filter-iterator-models" id="id60" name="id60"><tt class="literal"><span class="pre">filter_iterator</span></tt> models</a></li>
<li><a class="reference" href="#filter-iterator-operations" id="id61" name="id61"><tt class="literal"><span class="pre">filter_iterator</span></tt> operations</a></li>
</ul>
</li>
<li><a class="reference" href="#counting-iterator" id="id63" name="id63">Counting iterator</a><ul>
<li><a class="reference" href="#class-template-counting-iterator" id="id64" name="id64">Class template <tt class="literal"><span class="pre">counting_iterator</span></tt></a></li>
<li><a class="reference" href="#counting-iterator-requirements" id="id65" name="id65"><tt class="literal"><span class="pre">counting_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#counting-iterator-models" id="id66" name="id66"><tt class="literal"><span class="pre">counting_iterator</span></tt> models</a></li>
<li><a class="reference" href="#counting-iterator-operations" id="id67" name="id67"><tt class="literal"><span class="pre">counting_iterator</span></tt> operations</a></li>
<li><a class="reference" href="#counting-iterator" id="id62" name="id62">Counting iterator</a><ul>
<li><a class="reference" href="#class-template-counting-iterator" id="id63" name="id63">Class template <tt class="literal"><span class="pre">counting_iterator</span></tt></a></li>
<li><a class="reference" href="#counting-iterator-requirements" id="id64" name="id64"><tt class="literal"><span class="pre">counting_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#counting-iterator-models" id="id65" name="id65"><tt class="literal"><span class="pre">counting_iterator</span></tt> models</a></li>
<li><a class="reference" href="#counting-iterator-operations" id="id66" name="id66"><tt class="literal"><span class="pre">counting_iterator</span></tt> operations</a></li>
</ul>
</li>
<li><a class="reference" href="#function-output-iterator" id="id68" name="id68">Function output iterator</a><ul>
<li><a class="reference" href="#class-template-function-output-iterator" id="id69" name="id69">Class template <tt class="literal"><span class="pre">function_output_iterator</span></tt></a></li>
<li><a class="reference" href="#function-output-iterator-requirements" id="id70" name="id70"><tt class="literal"><span class="pre">function_output_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#function-output-iterator-models" id="id71" name="id71"><tt class="literal"><span class="pre">function_output_iterator</span></tt> models</a></li>
<li><a class="reference" href="#function-output-iterator-operations" id="id72" name="id72"><tt class="literal"><span class="pre">function_output_iterator</span></tt> operations</a></li>
<li><a class="reference" href="#function-output-iterator" id="id67" name="id67">Function output iterator</a><ul>
<li><a class="reference" href="#class-template-function-output-iterator" id="id68" name="id68">Class template <tt class="literal"><span class="pre">function_output_iterator</span></tt></a></li>
<li><a class="reference" href="#function-output-iterator-requirements" id="id69" name="id69"><tt class="literal"><span class="pre">function_output_iterator</span></tt> requirements</a></li>
<li><a class="reference" href="#function-output-iterator-models" id="id70" name="id70"><tt class="literal"><span class="pre">function_output_iterator</span></tt> models</a></li>
<li><a class="reference" href="#function-output-iterator-operations" id="id71" name="id71"><tt class="literal"><span class="pre">function_output_iterator</span></tt> operations</a></li>
</ul>
</li>
</ul>
@@ -625,7 +624,7 @@ public:
typedef Reference reference;
typedef Value* pointer;
typedef Difference difference_type;
typedef /* see <a class="reference" href="#facade-iterator-category">below</a> */ iterator_category;
typedef /* see <a class="reference" href="#iterator-category">below</a> */ iterator_category;
reference operator*() const;
/* see <a class="reference" href="#operator-arrow">below</a> */ operator-&gt;() const;
@@ -694,6 +693,39 @@ template &lt;class Derived, class V, class TC, class R, class D&gt;
Derived operator+ (iterator_facade&lt;Derived, V, TC, R, D&gt; const&amp;,
typename Derived::difference_type n)
</pre>
<a class="target" id="iterator-category" name="iterator-category"></a><p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member of <tt class="literal"><span class="pre">iterator_facade</span></tt> is
<tt class="literal"><span class="pre">facade_iterator_category(CategoryOrTraversal,</span> <span class="pre">value_type,</span>
<span class="pre">reference)</span></tt>, as specified by the following pseudo-code:</p>
<pre class="literal-block">
facade_iterator_category(C, V, R) =
if (C is convertible to input_iterator_tag or output_iterator_tag) then
return C
else if (C is convertible to incrementable_traversal_tag) then
if (R is a reference type
and C is convertible to forward_traversal_tag) then
if (C is convertible to random_access_traversal_tag)
return a type convertible to random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
return a type convertible to bidirectional_iterator_tag
else
return a type convertible to forward_iterator_tag
else if (C is convertible to single_pass_traversal_tag
and R is convertible to V)
return a type convertible to input_iterator_tag
else
return C
</pre>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
<p>If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is <tt class="literal"><span class="pre">use_default</span></tt> then
<tt class="literal"><span class="pre">iterator_traversal&lt;Derived&gt;::type</span></tt> is convertible to the most
derived standard traversal tag type to which
<tt class="literal"><span class="pre">iterator_traversal&lt;Iterator&gt;::type</span></tt> is also convertible, and not to
any more-derived traversal tag type. Otherwise
<tt class="literal"><span class="pre">iterator_traversal&lt;Derived&gt;::type</span></tt> is convertible to the most
derived standard traversal tag type to which <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>
is also convertible, and not to any more-derived traversal tag type.</p>
<p>The <tt class="literal"><span class="pre">enable_if_interoperable</span></tt> template used above is for exposition
purposes. The member operators should be only be in an overload set
provided the derived types <tt class="literal"><span class="pre">Dr1</span></tt> and <tt class="literal"><span class="pre">Dr2</span></tt> are interoperable,
@@ -758,8 +790,7 @@ Iterator</td>
<tr><td><tt class="literal"><span class="pre">c.equal(y)</span></tt></td>
<td>convertible to bool</td>
<td>true iff <tt class="literal"><span class="pre">c</span></tt> and <tt class="literal"><span class="pre">y</span></tt> refer to the
same position. Implements <tt class="literal"><span class="pre">c</span> <span class="pre">==</span> <span class="pre">y</span></tt>
and <tt class="literal"><span class="pre">c</span> <span class="pre">!=</span> <span class="pre">y</span></tt>.</td>
same position.</td>
<td>Single Pass Iterator</td>
</tr>
<tr><td><tt class="literal"><span class="pre">a.increment()</span></tt></td>
@@ -779,77 +810,19 @@ Iterator</td>
<td>Random Access Traversal
Iterator</td>
</tr>
<tr><td><tt class="literal"><span class="pre">c.distance_to(b)</span></tt></td>
<td>convertible to
<tt class="literal"><span class="pre">F::difference_type</span></tt></td>
<td>equivalent to <tt class="literal"><span class="pre">distance(c,</span> <span class="pre">b)</span></tt></td>
<td>Random Access Traversal
Iterator</td>
</tr>
<tr><td><tt class="literal"><span class="pre">c.distance_to(z)</span></tt></td>
<td>convertible to
<tt class="literal"><span class="pre">F::difference_type</span></tt></td>
<td>equivalent to <tt class="literal"><span class="pre">distance(c,</span> <span class="pre">z)</span></tt>.
Implements <tt class="literal"><span class="pre">c</span> <span class="pre">-</span> <span class="pre">z</span></tt>, <tt class="literal"><span class="pre">c</span> <span class="pre">&lt;</span> <span class="pre">z</span></tt>, <tt class="literal"><span class="pre">c</span>
<span class="pre">&lt;=</span> <span class="pre">z</span></tt>, <tt class="literal"><span class="pre">c</span> <span class="pre">&gt;</span> <span class="pre">z</span></tt>, and <tt class="literal"><span class="pre">c</span> <span class="pre">&gt;=</span> <span class="pre">c</span></tt>.</td>
<td>equivalent to <tt class="literal"><span class="pre">distance(c,</span> <span class="pre">X(z))</span></tt>.</td>
<td>Random Access Traversal
Iterator</td>
</tr>
</tbody>
</table>
</div>
<a class="target" id="facade-iterator-category" name="facade-iterator-category"></a></div>
<div class="section" id="iterator-facade-iterator-category">
<h3><a class="toc-backref" href="#id30" name="iterator-facade-iterator-category"><tt class="literal"><span class="pre">iterator_facade</span></tt> iterator category</a></h3>
<p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member of <tt class="literal"><span class="pre">iterator_facade&lt;X,V,R,C,D&gt;</span></tt>
satisfies the following conditions:</p>
<ul>
<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
<tt class="literal"><span class="pre">iterator_category</span></tt> is the same as <tt class="literal"><span class="pre">C</span></tt>.</p>
</li>
<li><p class="first">Otherwise, if <tt class="literal"><span class="pre">C</span></tt> is not convertible to
<tt class="literal"><span class="pre">incrementable_traversal_tag</span></tt>, the program is ill-formed</p>
</li>
<li><p class="first">Otherwise:</p>
<ul>
<li><p class="first"><tt class="literal"><span class="pre">iterator_category</span></tt> is convertible to the iterator
category tag or tags given by the following algorithm, and
not to any more-derived iterator category tag or tags:</p>
<pre class="literal-block">
if (R is a reference type
&amp;&amp; C is convertible to forward_traversal_tag)
{
if (C is convertible to random_access_traversal_tag)
random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
bidirectional_iterator_tag
else
forward_iterator_tag
}
else
{
if (C is convertible to single_pass_traversal_tag
&amp;&amp; R is convertible to V)
input_iterator_tag
else
C
}
</pre>
</li>
<li><p class="first"><tt class="literal"><span class="pre">iterator_traversal&lt;X&gt;::type</span></tt> is convertible to the most
derived traversal tag type to which <tt class="literal"><span class="pre">C</span></tt> is also
convertible, and not to any more-derived traversal tag type.</p>
</li>
</ul>
</li>
</ul>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
</div>
<div class="section" id="iterator-facade-operations">
<h3><a class="toc-backref" href="#id31" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h3>
<h3><a class="toc-backref" href="#id30" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h3>
<p>The operations in this section are described in terms of operations on
the core interface of <tt class="literal"><span class="pre">Derived</span></tt> which may be inaccessible
(i.e. private). The implementation should access these operations
@@ -887,11 +860,10 @@ of type <tt class="literal"><span class="pre">pointer</span></tt> equal to:</p>
<tbody valign="top">
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">an object convertible to <tt class="literal"><span class="pre">value_type</span></tt>. For constant
objects <tt class="literal"><span class="pre">v</span></tt> of type <tt class="literal"><span class="pre">value_type</span></tt>, and <tt class="literal"><span class="pre">n</span></tt> of type
<tt class="literal"><span class="pre">difference_type</span></tt>, and reference <tt class="literal"><span class="pre">p</span></tt> equal to
<tt class="literal"><span class="pre">*static_cast&lt;Derived</span> <span class="pre">const*&gt;(this)</span></tt>, <tt class="literal"><span class="pre">(*this)[n]</span> <span class="pre">=</span> <span class="pre">v</span></tt> is
equivalent to <tt class="literal"><span class="pre">*(p+</span> <span class="pre">n)</span> <span class="pre">=</span> <span class="pre">v</span></tt>, and <tt class="literal"><span class="pre">static_cast&lt;value_type</span>
<tt class="literal"><span class="pre">difference_type</span></tt>, <tt class="literal"><span class="pre">(*this)[n]</span> <span class="pre">=</span> <span class="pre">v</span></tt> is equivalent to
<tt class="literal"><span class="pre">*(*this</span> <span class="pre">+</span> <span class="pre">n)</span> <span class="pre">=</span> <span class="pre">v</span></tt>, and <tt class="literal"><span class="pre">static_cast&lt;value_type</span>
<span class="pre">const&amp;&gt;((*this)[n])</span></tt> is equivalent to
<tt class="literal"><span class="pre">static_cast&lt;value_type</span> <span class="pre">const&amp;&gt;(*(p+n))</span></tt></td>
<tt class="literal"><span class="pre">static_cast&lt;value_type</span> <span class="pre">const&amp;&gt;(*(*this</span> <span class="pre">+</span> <span class="pre">n))</span></tt></td>
</tr>
</tbody>
</table>
@@ -991,7 +963,7 @@ return tmp -= n;
</div>
</div>
<div class="section" id="iterator-adaptor-lib-iterator-adaptor">
<h2><a class="toc-backref" href="#id32" name="iterator-adaptor-lib-iterator-adaptor">Iterator adaptor [lib.iterator.adaptor]</a></h2>
<h2><a class="toc-backref" href="#id31" name="iterator-adaptor-lib-iterator-adaptor">Iterator adaptor [lib.iterator.adaptor]</a></h2>
<!-- Version 1.1 of this ReStructuredText document corresponds to
n1530_, the paper accepted by the LWG. -->
<!-- Copyright David Abrahams, Jeremy Siek, and Thomas Witt 2003. All
@@ -1007,7 +979,7 @@ depends on the operations supported by the <tt class="literal"><span class="pre"
core interface functions of <tt class="literal"><span class="pre">iterator_facade</span></tt> are redefined in the
<tt class="literal"><span class="pre">Derived</span></tt> class.</p>
<div class="section" id="class-template-iterator-adaptor">
<h3><a class="toc-backref" href="#id33" name="class-template-iterator-adaptor">Class template <tt class="literal"><span class="pre">iterator_adaptor</span></tt></a></h3>
<h3><a class="toc-backref" href="#id32" name="class-template-iterator-adaptor">Class template <tt class="literal"><span class="pre">iterator_adaptor</span></tt></a></h3>
<!-- Version 1.4 of this ReStructuredText document corresponds to
n1530_, the paper accepted by the LWG for TR1. -->
<!-- Copyright David Abrahams, Jeremy Siek, and Thomas Witt 2003. All
@@ -1056,13 +1028,13 @@ class iterator_adaptor
</pre>
<a class="target" id="requirements" name="requirements"></a></div>
<div class="section" id="iterator-adaptor-requirements">
<h3><a class="toc-backref" href="#id34" name="iterator-adaptor-requirements"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> requirements</a></h3>
<h3><a class="toc-backref" href="#id33" name="iterator-adaptor-requirements"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> requirements</a></h3>
<p>The <tt class="literal"><span class="pre">Derived</span></tt> template argument must be a publicly derived from
<tt class="literal"><span class="pre">iterator_adaptor</span></tt>.</p>
<p>The <tt class="literal"><span class="pre">Base</span></tt> argument shall be Assignable and Copy Constructible.</p>
<a class="target" id="base-parameters" name="base-parameters"></a></div>
<div class="section" id="iterator-adaptor-base-class-parameters">
<h3><a class="toc-backref" href="#id35" name="iterator-adaptor-base-class-parameters"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> base class parameters</a></h3>
<h3><a class="toc-backref" href="#id34" name="iterator-adaptor-base-class-parameters"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> base class parameters</a></h3>
<p>The <em>V</em>, <em>C</em>, <em>R</em>, and <em>D</em> parameters of the <tt class="literal"><span class="pre">iterator_facade</span></tt>
used as a base class in the summary of <tt class="literal"><span class="pre">iterator_adaptor</span></tt>
above are defined as follows:</p>
@@ -1092,7 +1064,7 @@ above are defined as follows:</p>
</pre>
</div>
<div class="section" id="iterator-adaptor-models">
<h3><a class="toc-backref" href="#id36" name="iterator-adaptor-models"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> models</a></h3>
<h3><a class="toc-backref" href="#id35" name="iterator-adaptor-models"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> models</a></h3>
<p>In order for <tt class="literal"><span class="pre">Derived</span></tt> to model the iterator concepts corresponding
to <tt class="literal"><span class="pre">iterator_traits&lt;Derived&gt;::iterator_category</span></tt>, the expressions
involving <tt class="literal"><span class="pre">m_iterator</span></tt> in the specifications of those private member
@@ -1102,7 +1074,7 @@ expression involving <tt class="literal"><span class="pre">Derived</span></tt> i
<!-- The above is confusing and needs a rewrite. -JGS -->
</div>
<div class="section" id="iterator-adaptor-public-operations">
<h3><a class="toc-backref" href="#id37" name="iterator-adaptor-public-operations"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> public operations</a></h3>
<h3><a class="toc-backref" href="#id36" name="iterator-adaptor-public-operations"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> public operations</a></h3>
<p><tt class="literal"><span class="pre">iterator_adaptor();</span></tt></p>
<table class="field-list" frame="void" rules="none">
<col class="field-name" />
@@ -1136,7 +1108,7 @@ expression involving <tt class="literal"><span class="pre">Derived</span></tt> i
</table>
</div>
<div class="section" id="iterator-adaptor-protected-member-functions">
<h3><a class="toc-backref" href="#id38" name="iterator-adaptor-protected-member-functions"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> protected member functions</a></h3>
<h3><a class="toc-backref" href="#id37" name="iterator-adaptor-protected-member-functions"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> protected member functions</a></h3>
<p><tt class="literal"><span class="pre">Base</span> <span class="pre">const&amp;</span> <span class="pre">base_reference()</span> <span class="pre">const;</span></tt></p>
<table class="field-list" frame="void" rules="none">
<col class="field-name" />
@@ -1157,7 +1129,7 @@ expression involving <tt class="literal"><span class="pre">Derived</span></tt> i
</table>
</div>
<div class="section" id="iterator-adaptor-private-member-functions">
<h3><a class="toc-backref" href="#id39" name="iterator-adaptor-private-member-functions"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> private member functions</a></h3>
<h3><a class="toc-backref" href="#id38" name="iterator-adaptor-private-member-functions"><tt class="literal"><span class="pre">iterator_adaptor</span></tt> private member functions</a></h3>
<p><tt class="literal"><span class="pre">typename</span> <span class="pre">iterator_adaptor::reference</span> <span class="pre">dereference()</span> <span class="pre">const;</span></tt></p>
<table class="field-list" frame="void" rules="none">
<col class="field-name" />
@@ -1226,7 +1198,7 @@ typename iterator_adaptor::difference_type distance_to(
</div>
</div>
<div class="section" id="specialized-adaptors-lib-iterator-special-adaptors">
<h2><a class="toc-backref" href="#id40" name="specialized-adaptors-lib-iterator-special-adaptors">Specialized adaptors [lib.iterator.special.adaptors]</a></h2>
<h2><a class="toc-backref" href="#id39" name="specialized-adaptors-lib-iterator-special-adaptors">Specialized adaptors [lib.iterator.special.adaptors]</a></h2>
<p>The <tt class="literal"><span class="pre">enable_if_convertible&lt;X,Y&gt;::type</span></tt> expression used in
this section is for exposition purposes. The converting constructors
for specialized adaptors should be only be in an overload set provided
@@ -1255,7 +1227,7 @@ take the constructor out of the overload set when the types are not
implicitly convertible.
]</p>
<div class="section" id="indirect-iterator">
<h3><a class="toc-backref" href="#id41" name="indirect-iterator">Indirect iterator</a></h3>
<h3><a class="toc-backref" href="#id40" name="indirect-iterator">Indirect iterator</a></h3>
<p><tt class="literal"><span class="pre">indirect_iterator</span></tt> adapts an iterator by applying an
<em>extra</em> dereference inside of <tt class="literal"><span class="pre">operator*()</span></tt>. For example, this
iterator adaptor makes it possible to view a container of pointers
@@ -1265,7 +1237,7 @@ auxiliary traits, <tt class="literal"><span class="pre">pointee</span></tt> and
provide support for underlying iterators whose <tt class="literal"><span class="pre">value_type</span></tt> is
not an iterator.</p>
<div class="section" id="class-template-pointee">
<h4><a class="toc-backref" href="#id42" name="class-template-pointee">Class template <tt class="literal"><span class="pre">pointee</span></tt></a></h4>
<h4><a class="toc-backref" href="#id41" name="class-template-pointee">Class template <tt class="literal"><span class="pre">pointee</span></tt></a></h4>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
@@ -1309,7 +1281,7 @@ else
</pre>
</div>
<div class="section" id="class-template-indirect-reference">
<h4><a class="toc-backref" href="#id43" name="class-template-indirect-reference">Class template <tt class="literal"><span class="pre">indirect_reference</span></tt></a></h4>
<h4><a class="toc-backref" href="#id42" name="class-template-indirect-reference">Class template <tt class="literal"><span class="pre">indirect_reference</span></tt></a></h4>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
@@ -1344,7 +1316,7 @@ else
</pre>
</div>
<div class="section" id="class-template-indirect-iterator">
<h4><a class="toc-backref" href="#id44" name="class-template-indirect-iterator">Class template <tt class="literal"><span class="pre">indirect_iterator</span></tt></a></h4>
<h4><a class="toc-backref" href="#id43" name="class-template-indirect-iterator">Class template <tt class="literal"><span class="pre">indirect_iterator</span></tt></a></h4>
<pre class="literal-block">
template &lt;
class Iterator
@@ -1411,60 +1383,13 @@ if (Difference is use_default)
else
typedef Difference difference_type;
</pre>
<p><tt class="literal"><span class="pre">iterator_category</span></tt> satisfies the following conditions, where
<tt class="literal"><span class="pre">R</span></tt> is <tt class="literal"><span class="pre">reference</span></tt> and <tt class="literal"><span class="pre">V</span></tt> is <tt class="literal"><span class="pre">value_type</span></tt>, and where: if
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is <tt class="literal"><span class="pre">use_default</span></tt>, <tt class="literal"><span class="pre">C</span></tt> is
<tt class="literal"><span class="pre">iterator_traversal&lt;Iterator&gt;::type</span></tt> and otherwise <tt class="literal"><span class="pre">C</span></tt> is
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>.</p>
<blockquote>
<ul>
<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
<tt class="literal"><span class="pre">iterator_category</span></tt> is the same as <tt class="literal"><span class="pre">C</span></tt>.</p>
</li>
<li><p class="first">Otherwise, if <tt class="literal"><span class="pre">C</span></tt> is not convertible to
<tt class="literal"><span class="pre">incrementable_traversal_tag</span></tt>, the program is ill-formed</p>
</li>
<li><p class="first">Otherwise:</p>
<ul>
<li><p class="first"><tt class="literal"><span class="pre">iterator_category</span></tt> is convertible to the iterator
category tag or tags given by the following algorithm, and
not to any more-derived iterator category tag or tags:</p>
<pre class="literal-block">
if (R is a reference type
&amp;&amp; C is convertible to forward_traversal_tag)
{
if (C is convertible to random_access_traversal_tag)
random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
bidirectional_iterator_tag
else
forward_iterator_tag
}
else
{
if (C is convertible to single_pass_traversal_tag
&amp;&amp; R is convertible to V)
input_iterator_tag
else
C
}
</pre>
</li>
<li><p class="first"><tt class="literal"><span class="pre">iterator_traversal&lt;X&gt;::type</span></tt> is convertible to the most
derived traversal tag type to which <tt class="literal"><span class="pre">C</span></tt> is also
convertible, and not to any more-derived traversal tag type.</p>
</li>
</ul>
</li>
</ul>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
</blockquote>
<p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member is <tt class="literal"><span class="pre">facade_iterator_category(C,</span>
<span class="pre">value_type,</span> <span class="pre">reference)</span></tt> where if <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is
<tt class="literal"><span class="pre">use_default</span></tt>, <tt class="literal"><span class="pre">C</span></tt> is <tt class="literal"><span class="pre">iterator_traversal&lt;Iterator&gt;::type</span></tt> and
otherwise <tt class="literal"><span class="pre">C</span></tt> is <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>.</p>
</div>
<div class="section" id="indirect-iterator-requirements">
<h4><a class="toc-backref" href="#id45" name="indirect-iterator-requirements"><tt class="literal"><span class="pre">indirect_iterator</span></tt> requirements</a></h4>
<h4><a class="toc-backref" href="#id44" name="indirect-iterator-requirements"><tt class="literal"><span class="pre">indirect_iterator</span></tt> requirements</a></h4>
<p>The expression <tt class="literal"><span class="pre">*v</span></tt>, where <tt class="literal"><span class="pre">v</span></tt> is an object of
<tt class="literal"><span class="pre">iterator_traits&lt;Iterator&gt;::value_type</span></tt>, shall be valid
expression and convertible to <tt class="literal"><span class="pre">reference</span></tt>. <tt class="literal"><span class="pre">Iterator</span></tt> shall
@@ -1478,7 +1403,7 @@ parameter is not <tt class="literal"><span class="pre">use_default</span></tt>,
deducing the default for the <tt class="literal"><span class="pre">value_type</span></tt> member.]</p>
</div>
<div class="section" id="indirect-iterator-models">
<h4><a class="toc-backref" href="#id46" name="indirect-iterator-models"><tt class="literal"><span class="pre">indirect_iterator</span></tt> models</a></h4>
<h4><a class="toc-backref" href="#id45" name="indirect-iterator-models"><tt class="literal"><span class="pre">indirect_iterator</span></tt> models</a></h4>
<p>In addition to the concepts indicated by <tt class="literal"><span class="pre">iterator_category</span></tt>
and by <tt class="literal"><span class="pre">iterator_traversal&lt;indirect_iterator&gt;::type</span></tt>, a
specialization of <tt class="literal"><span class="pre">indirect_iterator</span></tt> models the following
@@ -1499,7 +1424,7 @@ expression (where <tt class="literal"><span class="pre">t</span></tt> is an obje
interoperable with iterator <tt class="literal"><span class="pre">Y</span></tt>.</p>
</div>
<div class="section" id="indirect-iterator-operations">
<h4><a class="toc-backref" href="#id47" name="indirect-iterator-operations"><tt class="literal"><span class="pre">indirect_iterator</span></tt> operations</a></h4>
<h4><a class="toc-backref" href="#id46" name="indirect-iterator-operations"><tt class="literal"><span class="pre">indirect_iterator</span></tt> operations</a></h4>
<p>In addition to the operations required by the concepts described
above, specializations of <tt class="literal"><span class="pre">indirect_iterator</span></tt> provide the
following operations.</p>
@@ -1591,11 +1516,11 @@ indirect_iterator(
</div>
</div>
<div class="section" id="reverse-iterator">
<h3><a class="toc-backref" href="#id48" name="reverse-iterator">Reverse iterator</a></h3>
<h3><a class="toc-backref" href="#id47" name="reverse-iterator">Reverse iterator</a></h3>
<p>The reverse iterator adaptor iterates through the adapted iterator
range in the opposite direction.</p>
<div class="section" id="class-template-reverse-iterator">
<h4><a class="toc-backref" href="#id49" name="class-template-reverse-iterator">Class template <tt class="literal"><span class="pre">reverse_iterator</span></tt></a></h4>
<h4><a class="toc-backref" href="#id48" name="class-template-reverse-iterator">Class template <tt class="literal"><span class="pre">reverse_iterator</span></tt></a></h4>
<pre class="literal-block">
template &lt;class Iterator&gt;
class reverse_iterator
@@ -1632,11 +1557,11 @@ Lvalue Iterator, then <tt class="literal"><span class="pre">iterator_category</s
convertible to <tt class="literal"><span class="pre">input_iterator_tag</span></tt>.</p>
</div>
<div class="section" id="reverse-iterator-requirements">
<h4><a class="toc-backref" href="#id50" name="reverse-iterator-requirements"><tt class="literal"><span class="pre">reverse_iterator</span></tt> requirements</a></h4>
<h4><a class="toc-backref" href="#id49" name="reverse-iterator-requirements"><tt class="literal"><span class="pre">reverse_iterator</span></tt> requirements</a></h4>
<p><tt class="literal"><span class="pre">Iterator</span></tt> must be a model of Bidirectional Traversal Iterator.</p>
</div>
<div class="section" id="reverse-iterator-models">
<h4><a class="toc-backref" href="#id51" name="reverse-iterator-models"><tt class="literal"><span class="pre">reverse_iterator</span></tt> models</a></h4>
<h4><a class="toc-backref" href="#id50" name="reverse-iterator-models"><tt class="literal"><span class="pre">reverse_iterator</span></tt> models</a></h4>
<p>A specialization of <tt class="literal"><span class="pre">reverse_iterator</span></tt> models the same standard
traversal and access iterator concepts modeled by its <tt class="literal"><span class="pre">Iterator</span></tt>
argument. In addition, it models the old iterator concepts
@@ -1674,7 +1599,7 @@ Random Access Traversal Iterator</td>
if and only if iterator <tt class="literal"><span class="pre">X</span></tt> is interoperable with iterator <tt class="literal"><span class="pre">Y</span></tt>.</p>
</div>
<div class="section" id="reverse-iterator-operations">
<h4><a class="toc-backref" href="#id52" name="reverse-iterator-operations"><tt class="literal"><span class="pre">reverse_iterator</span></tt> operations</a></h4>
<h4><a class="toc-backref" href="#id51" name="reverse-iterator-operations"><tt class="literal"><span class="pre">reverse_iterator</span></tt> operations</a></h4>
<p>In addition to the operations required by the concepts modeled by
<tt class="literal"><span class="pre">reverse_iterator</span></tt>, <tt class="literal"><span class="pre">reverse_iterator</span></tt> provides the following
operations.</p>
@@ -1764,12 +1689,12 @@ return *--tmp;
</div>
</div>
<div class="section" id="transform-iterator">
<h3><a class="toc-backref" href="#id53" name="transform-iterator">Transform iterator</a></h3>
<h3><a class="toc-backref" href="#id52" name="transform-iterator">Transform iterator</a></h3>
<p>The transform iterator adapts an iterator by modifying the
<tt class="literal"><span class="pre">operator*</span></tt> to apply a function object to the result of
dereferencing the iterator and returning the result.</p>
<div class="section" id="class-template-transform-iterator">
<h4><a class="toc-backref" href="#id54" name="class-template-transform-iterator">Class template <tt class="literal"><span class="pre">transform_iterator</span></tt></a></h4>
<h4><a class="toc-backref" href="#id53" name="class-template-transform-iterator">Class template <tt class="literal"><span class="pre">transform_iterator</span></tt></a></h4>
<!-- Version 1.3 of this document was accepted for TR1 -->
<pre class="literal-block">
template &lt;class UnaryFunction,
@@ -1822,7 +1747,7 @@ model Readable Lvalue Iterator then <tt class="literal"><span class="pre">iterat
convertible to <tt class="literal"><span class="pre">input_iterator_tag</span></tt>.</p>
</div>
<div class="section" id="transform-iterator-requirements">
<h4><a class="toc-backref" href="#id55" name="transform-iterator-requirements"><tt class="literal"><span class="pre">transform_iterator</span></tt> requirements</a></h4>
<h4><a class="toc-backref" href="#id54" name="transform-iterator-requirements"><tt class="literal"><span class="pre">transform_iterator</span></tt> requirements</a></h4>
<p>The type <tt class="literal"><span class="pre">UnaryFunction</span></tt> must be Assignable, Copy Constructible, and
the expression <tt class="literal"><span class="pre">f(*i)</span></tt> must be valid where <tt class="literal"><span class="pre">f</span></tt> is an object of
type <tt class="literal"><span class="pre">UnaryFunction</span></tt>, <tt class="literal"><span class="pre">i</span></tt> is an object of type <tt class="literal"><span class="pre">Iterator</span></tt>, and
@@ -1831,7 +1756,7 @@ where the type of <tt class="literal"><span class="pre">f(*i)</span></tt> must b
<p>The argument <tt class="literal"><span class="pre">Iterator</span></tt> shall model Readable Iterator.</p>
</div>
<div class="section" id="transform-iterator-models">
<h4><a class="toc-backref" href="#id56" name="transform-iterator-models"><tt class="literal"><span class="pre">transform_iterator</span></tt> models</a></h4>
<h4><a class="toc-backref" href="#id55" name="transform-iterator-models"><tt class="literal"><span class="pre">transform_iterator</span></tt> models</a></h4>
<p>The resulting <tt class="literal"><span class="pre">transform_iterator</span></tt> models the most refined of the
following options that is also modeled by <tt class="literal"><span class="pre">Iterator</span></tt>.</p>
<blockquote>
@@ -1878,7 +1803,7 @@ mutable iterator (as defined in the old iterator requirements).</p>
interoperable with iterator <tt class="literal"><span class="pre">Y</span></tt>.</p>
</div>
<div class="section" id="transform-iterator-operations">
<h4><a class="toc-backref" href="#id57" name="transform-iterator-operations"><tt class="literal"><span class="pre">transform_iterator</span></tt> operations</a></h4>
<h4><a class="toc-backref" href="#id56" name="transform-iterator-operations"><tt class="literal"><span class="pre">transform_iterator</span></tt> operations</a></h4>
<p>In addition to the operations required by the concepts modeled by
<tt class="literal"><span class="pre">transform_iterator</span></tt>, <tt class="literal"><span class="pre">transform_iterator</span></tt> provides the following
operations.</p>
@@ -1971,7 +1896,7 @@ transform_iterator(
</div>
</div>
<div class="section" id="filter-iterator">
<h3><a class="toc-backref" href="#id58" name="filter-iterator">Filter iterator</a></h3>
<h3><a class="toc-backref" href="#id57" name="filter-iterator">Filter iterator</a></h3>
<p>The filter iterator adaptor creates a view of an iterator range in
which some elements of the range are skipped. A predicate function
object controls which elements are skipped. When the predicate is
@@ -1983,7 +1908,7 @@ underlying range. A filter iterator is therefore constructed with pair
of iterators indicating the range of elements in the unfiltered
sequence to be traversed.</p>
<div class="section" id="class-template-filter-iterator">
<h4><a class="toc-backref" href="#id59" name="class-template-filter-iterator">Class template <tt class="literal"><span class="pre">filter_iterator</span></tt></a></h4>
<h4><a class="toc-backref" href="#id58" name="class-template-filter-iterator">Class template <tt class="literal"><span class="pre">filter_iterator</span></tt></a></h4>
<!-- Copyright David Abrahams, Jeremy Siek, and Thomas Witt -->
<!-- 2004. Use, modification and distribution is subject to the Boost -->
<!-- Software License, Version 1.0. (See accompanying file -->
@@ -2024,7 +1949,7 @@ Iterator then <tt class="literal"><span class="pre">iterator_category</span></tt
convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt>.</p>
</div>
<div class="section" id="filter-iterator-requirements">
<h4><a class="toc-backref" href="#id60" name="filter-iterator-requirements"><tt class="literal"><span class="pre">filter_iterator</span></tt> requirements</a></h4>
<h4><a class="toc-backref" href="#id59" name="filter-iterator-requirements"><tt class="literal"><span class="pre">filter_iterator</span></tt> requirements</a></h4>
<p>The <tt class="literal"><span class="pre">Predicate</span></tt> argument must be Assignable, Copy Constructible, and
the expression <tt class="literal"><span class="pre">p(x)</span></tt> must be valid where <tt class="literal"><span class="pre">p</span></tt> is an object of type
<tt class="literal"><span class="pre">Predicate</span></tt>, <tt class="literal"><span class="pre">x</span></tt> is an object of type
@@ -2035,7 +1960,7 @@ Iterator and Single Pass Iterator or it shall meet the requirements of
Input Iterator.</p>
</div>
<div class="section" id="filter-iterator-models">
<h4><a class="toc-backref" href="#id61" name="filter-iterator-models"><tt class="literal"><span class="pre">filter_iterator</span></tt> models</a></h4>
<h4><a class="toc-backref" href="#id60" name="filter-iterator-models"><tt class="literal"><span class="pre">filter_iterator</span></tt> models</a></h4>
<p>The concepts that <tt class="literal"><span class="pre">filter_iterator</span></tt> models are dependent on which
concepts the <tt class="literal"><span class="pre">Iterator</span></tt> argument models, as specified in the
following tables.</p>
@@ -2106,7 +2031,7 @@ following tables.</p>
if and only if iterator <tt class="literal"><span class="pre">X</span></tt> is interoperable with iterator <tt class="literal"><span class="pre">Y</span></tt>.</p>
</div>
<div class="section" id="filter-iterator-operations">
<h4><a class="toc-backref" href="#id62" name="filter-iterator-operations"><tt class="literal"><span class="pre">filter_iterator</span></tt> operations</a></h4>
<h4><a class="toc-backref" href="#id61" name="filter-iterator-operations"><tt class="literal"><span class="pre">filter_iterator</span></tt> operations</a></h4>
<p>In addition to those operations required by the concepts that
<tt class="literal"><span class="pre">filter_iterator</span></tt> models, <tt class="literal"><span class="pre">filter_iterator</span></tt> provides the following
operations.</p>
@@ -2217,12 +2142,12 @@ or <tt class="literal"><span class="pre">m_pred(*m_iter)</span> <span class="pre
</div>
</div>
<div class="section" id="counting-iterator">
<h3><a class="toc-backref" href="#id63" name="counting-iterator">Counting iterator</a></h3>
<h3><a class="toc-backref" href="#id62" name="counting-iterator">Counting iterator</a></h3>
<p><tt class="literal"><span class="pre">counting_iterator</span></tt> adapts an object by adding an <tt class="literal"><span class="pre">operator*</span></tt> that
returns the current value of the object. All other iterator operations
are forwarded to the adapted object.</p>
<div class="section" id="class-template-counting-iterator">
<h4><a class="toc-backref" href="#id64" name="class-template-counting-iterator">Class template <tt class="literal"><span class="pre">counting_iterator</span></tt></a></h4>
<h4><a class="toc-backref" href="#id63" name="class-template-counting-iterator">Class template <tt class="literal"><span class="pre">counting_iterator</span></tt></a></h4>
<pre class="literal-block">
template &lt;
class Incrementable
@@ -2255,17 +2180,18 @@ type. Otherwise <tt class="literal"><span class="pre">difference_type</span></tt
<p>If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is not <tt class="literal"><span class="pre">use_default</span></tt> then the member
<tt class="literal"><span class="pre">iterator_category</span></tt> is <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>. Otherwise, if
<tt class="literal"><span class="pre">numeric_limits&lt;Incrementable&gt;::is_specialized</span></tt>, then
<tt class="literal"><span class="pre">iterator_category</span></tt> is a type convertible to
<tt class="literal"><span class="pre">random_access_iterator_tag</span></tt>. Otherwise, <tt class="literal"><span class="pre">iterator_category</span></tt> is
unspecified.</p>
<tt class="literal"><span class="pre">iterator_category</span></tt> is a
<tt class="literal"><span class="pre">facade_iterator_category(random_access_traversal_tag,</span> <span class="pre">Incrementable,</span> <span class="pre">const</span> <span class="pre">Incrementable&amp;)</span></tt>.
Otherwise, <tt class="literal"><span class="pre">iterator_category</span></tt> is
<tt class="literal"><span class="pre">facade_iterator_category(iterator_traversal&lt;Incrementable&gt;::type,</span> <span class="pre">Incrementable,</span> <span class="pre">const</span> <span class="pre">Incrementable&amp;)</span></tt>.</p>
<dl>
<dt>[<em>Note:</em> implementers are encouraged to provide an implementation of</dt>
<dd><tt class="literal"><span class="pre">operator-</span></tt> and a <tt class="literal"><span class="pre">difference_type</span></tt> that avoids overflows in
<dd><tt class="literal"><span class="pre">operator-</span></tt> and the default <tt class="literal"><span class="pre">difference_type</span></tt> that avoids overflows in
the cases when the <tt class="literal"><span class="pre">Incrementable</span></tt> type is a numeric type.]</dd>
</dl>
</div>
<div class="section" id="counting-iterator-requirements">
<h4><a class="toc-backref" href="#id65" name="counting-iterator-requirements"><tt class="literal"><span class="pre">counting_iterator</span></tt> requirements</a></h4>
<h4><a class="toc-backref" href="#id64" name="counting-iterator-requirements"><tt class="literal"><span class="pre">counting_iterator</span></tt> requirements</a></h4>
<p>The <tt class="literal"><span class="pre">Incrementable</span></tt> argument shall be Copy Constructible and Assignable.</p>
<p>If <tt class="literal"><span class="pre">iterator_category</span></tt> is convertible to <tt class="literal"><span class="pre">forward_iterator_tag</span></tt>
or <tt class="literal"><span class="pre">forward_traversal_tag</span></tt>, the following must be well-formed:</p>
@@ -2291,7 +2217,7 @@ i &lt; j;
</pre>
</div>
<div class="section" id="counting-iterator-models">
<h4><a class="toc-backref" href="#id66" name="counting-iterator-models"><tt class="literal"><span class="pre">counting_iterator</span></tt> models</a></h4>
<h4><a class="toc-backref" href="#id65" name="counting-iterator-models"><tt class="literal"><span class="pre">counting_iterator</span></tt> models</a></h4>
<p>Specializations of <tt class="literal"><span class="pre">counting_iterator</span></tt> model Readable Lvalue
Iterator. In addition, they model the concepts corresponding to the
iterator tags to which their <tt class="literal"><span class="pre">iterator_category</span></tt> is convertible.
@@ -2307,7 +2233,7 @@ concepts modeled by <tt class="literal"><span class="pre">Incrementable</span></
interoperable with iterator <tt class="literal"><span class="pre">Y</span></tt>.</p>
</div>
<div class="section" id="counting-iterator-operations">
<h4><a class="toc-backref" href="#id67" name="counting-iterator-operations"><tt class="literal"><span class="pre">counting_iterator</span></tt> operations</a></h4>
<h4><a class="toc-backref" href="#id66" name="counting-iterator-operations"><tt class="literal"><span class="pre">counting_iterator</span></tt> operations</a></h4>
<p>In addition to the operations required by the concepts modeled by
<tt class="literal"><span class="pre">counting_iterator</span></tt>, <tt class="literal"><span class="pre">counting_iterator</span></tt> provides the following
operations.</p>
@@ -2383,7 +2309,7 @@ operations.</p>
</div>
</div>
<div class="section" id="function-output-iterator">
<h3><a class="toc-backref" href="#id68" name="function-output-iterator">Function output iterator</a></h3>
<h3><a class="toc-backref" href="#id67" name="function-output-iterator">Function output iterator</a></h3>
<p>The function output iterator adaptor makes it easier to create custom
output iterators. The adaptor takes a unary function and creates a
model of Output Iterator. Each item assigned to the output iterator is
@@ -2392,7 +2318,7 @@ iterator is that creating a conforming output iterator is non-trivial,
particularly because the proper implementation usually requires a
proxy object.</p>
<div class="section" id="class-template-function-output-iterator">
<h4><a class="toc-backref" href="#id69" name="class-template-function-output-iterator">Class template <tt class="literal"><span class="pre">function_output_iterator</span></tt></a></h4>
<h4><a class="toc-backref" href="#id68" name="class-template-function-output-iterator">Class template <tt class="literal"><span class="pre">function_output_iterator</span></tt></a></h4>
<pre class="literal-block">
template &lt;class UnaryFunction&gt;
class function_output_iterator {
@@ -2414,16 +2340,16 @@ private:
</pre>
</div>
<div class="section" id="function-output-iterator-requirements">
<h4><a class="toc-backref" href="#id70" name="function-output-iterator-requirements"><tt class="literal"><span class="pre">function_output_iterator</span></tt> requirements</a></h4>
<h4><a class="toc-backref" href="#id69" name="function-output-iterator-requirements"><tt class="literal"><span class="pre">function_output_iterator</span></tt> requirements</a></h4>
<p><tt class="literal"><span class="pre">UnaryFunction</span></tt> must be Assignable and Copy Constructible.</p>
</div>
<div class="section" id="function-output-iterator-models">
<h4><a class="toc-backref" href="#id71" name="function-output-iterator-models"><tt class="literal"><span class="pre">function_output_iterator</span></tt> models</a></h4>
<h4><a class="toc-backref" href="#id70" name="function-output-iterator-models"><tt class="literal"><span class="pre">function_output_iterator</span></tt> models</a></h4>
<p><tt class="literal"><span class="pre">function_output_iterator</span></tt> is a model of the Writable and
Incrementable Iterator concepts.</p>
</div>
<div class="section" id="function-output-iterator-operations">
<h4><a class="toc-backref" href="#id72" name="function-output-iterator-operations"><tt class="literal"><span class="pre">function_output_iterator</span></tt> operations</a></h4>
<h4><a class="toc-backref" href="#id71" name="function-output-iterator-operations"><tt class="literal"><span class="pre">function_output_iterator</span></tt> operations</a></h4>
<p><tt class="literal"><span class="pre">explicit</span> <span class="pre">function_output_iterator(const</span> <span class="pre">UnaryFunction&amp;</span> <span class="pre">f</span> <span class="pre">=</span> <span class="pre">UnaryFunction());</span></tt></p>
<table class="field-list" frame="void" rules="none">
<col class="field-name" />
doc/facade_iterator_category.rst
+18 -32
View File
@@ -1,38 +1,24 @@
* if ``C`` is convertible to ``std::input_iterator_tag`` or
``C`` is convertible to ``std::output_iterator_tag``,
``iterator_category`` is the same as ``C``.
* Otherwise, if ``C`` is not convertible to
``incrementable_traversal_tag``, the program is ill-formed
* Otherwise:
::
- ``iterator_category`` is convertible to the iterator
category tag or tags given by the following algorithm, and
not to any more-derived iterator category tag or tags::
if (R is a reference type
&& C is convertible to forward_traversal_tag)
{
if (C is convertible to random_access_traversal_tag)
random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
bidirectional_iterator_tag
else
forward_iterator_tag
}
else
{
if (C is convertible to single_pass_traversal_tag
&& R is convertible to V)
input_iterator_tag
else
C
}
- ``iterator_traversal<X>::type`` is convertible to the most
derived traversal tag type to which ``C`` is also
convertible, and not to any more-derived traversal tag type.
facade_iterator_category(C, V, R) =
if (C is convertible to input_iterator_tag or output_iterator_tag) then
return C
else if (C is convertible to incrementable_traversal_tag) then
if (R is a reference type
and C is convertible to forward_traversal_tag) then
if (C is convertible to random_access_traversal_tag)
return a type convertible to random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
return a type convertible to bidirectional_iterator_tag
else
return a type convertible to forward_iterator_tag
else if (C is convertible to single_pass_traversal_tag
and R is convertible to V)
return a type convertible to input_iterator_tag
else
return C
.. Copyright David Abrahams 2004. Use, modification and distribution is
.. subject to the Boost Software License, Version 1.0. (See accompanying
doc/indirect_iterator.html
+4 -51
View File
@@ -125,57 +125,10 @@ if (Difference is use_default)
else
typedef Difference difference_type;
</pre>
<p><tt class="literal"><span class="pre">iterator_category</span></tt> satisfies the following conditions, where
<tt class="literal"><span class="pre">R</span></tt> is <tt class="literal"><span class="pre">reference</span></tt> and <tt class="literal"><span class="pre">V</span></tt> is <tt class="literal"><span class="pre">value_type</span></tt>, and where: if
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is <tt class="literal"><span class="pre">use_default</span></tt>, <tt class="literal"><span class="pre">C</span></tt> is
<tt class="literal"><span class="pre">iterator_traversal&lt;Iterator&gt;::type</span></tt> and otherwise <tt class="literal"><span class="pre">C</span></tt> is
<tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>.</p>
<blockquote>
<ul>
<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
<tt class="literal"><span class="pre">iterator_category</span></tt> is the same as <tt class="literal"><span class="pre">C</span></tt>.</p>
</li>
<li><p class="first">Otherwise, if <tt class="literal"><span class="pre">C</span></tt> is not convertible to
<tt class="literal"><span class="pre">incrementable_traversal_tag</span></tt>, the program is ill-formed</p>
</li>
<li><p class="first">Otherwise:</p>
<ul>
<li><p class="first"><tt class="literal"><span class="pre">iterator_category</span></tt> is convertible to the iterator
category tag or tags given by the following algorithm, and
not to any more-derived iterator category tag or tags:</p>
<pre class="literal-block">
if (R is a reference type
&amp;&amp; C is convertible to forward_traversal_tag)
{
if (C is convertible to random_access_traversal_tag)
random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
bidirectional_iterator_tag
else
forward_iterator_tag
}
else
{
if (C is convertible to single_pass_traversal_tag
&amp;&amp; R is convertible to V)
input_iterator_tag
else
C
}
</pre>
</li>
<li><p class="first"><tt class="literal"><span class="pre">iterator_traversal&lt;X&gt;::type</span></tt> is convertible to the most
derived traversal tag type to which <tt class="literal"><span class="pre">C</span></tt> is also
convertible, and not to any more-derived traversal tag type.</p>
</li>
</ul>
</li>
</ul>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
</blockquote>
<p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member is <tt class="literal"><span class="pre">facade_iterator_category(C,</span>
<span class="pre">value_type,</span> <span class="pre">reference)</span></tt> where if <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is
<tt class="literal"><span class="pre">use_default</span></tt>, <tt class="literal"><span class="pre">C</span></tt> is <tt class="literal"><span class="pre">iterator_traversal&lt;Iterator&gt;::type</span></tt> and
otherwise <tt class="literal"><span class="pre">C</span></tt> is <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>.</p>
</div>
<div class="section" id="indirect-iterator-requirements">
<h1><a class="toc-backref" href="#id3" name="indirect-iterator-requirements"><tt class="literal"><span class="pre">indirect_iterator</span></tt> requirements</a></h1>
doc/indirect_iterator_ref.rst
+6 -6
View File
@@ -66,13 +66,13 @@ following pseudo-code. We use the abbreviation
else
typedef Difference difference_type;
``iterator_category`` satisfies the following conditions, where
``R`` is ``reference`` and ``V`` is ``value_type``, and where: if
``CategoryOrTraversal`` is ``use_default``, ``C`` is
``iterator_traversal<Iterator>::type`` and otherwise ``C`` is
``CategoryOrTraversal``.
.. include:: facade_iterator_category.rst
The ``iterator_category`` member is ``facade_iterator_category(C,
value_type, reference)`` where if ``CategoryOrTraversal`` is
``use_default``, ``C`` is ``iterator_traversal<Iterator>::type`` and
otherwise ``C`` is ``CategoryOrTraversal``.
``indirect_iterator`` requirements
..................................
doc/iterator_facade.html
+71 -99
View File
@@ -54,29 +54,28 @@ and associated types, to be supplied by a derived iterator class.</td>
</li>
<li><a class="reference" href="#reference" id="id25" name="id25">Reference</a><ul>
<li><a class="reference" href="#iterator-facade-requirements" id="id26" name="id26"><tt class="literal"><span class="pre">iterator_facade</span></tt> Requirements</a></li>
<li><a class="reference" href="#iterator-facade-iterator-category" id="id27" name="id27"><tt class="literal"><span class="pre">iterator_facade</span></tt> iterator category</a></li>
<li><a class="reference" href="#iterator-facade-operations" id="id28" name="id28"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></li>
<li><a class="reference" href="#iterator-facade-operations" id="id27" name="id27"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></li>
</ul>
</li>
<li><a class="reference" href="#tutorial-example" id="id29" name="id29">Tutorial Example</a><ul>
<li><a class="reference" href="#the-problem" id="id30" name="id30">The Problem</a></li>
<li><a class="reference" href="#a-basic-iterator-using-iterator-facade" id="id31" name="id31">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
<li><a class="reference" href="#template-arguments-for-iterator-facade" id="id32" name="id32">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
<li><a class="reference" href="#derived" id="id33" name="id33"><tt class="literal"><span class="pre">Derived</span></tt></a></li>
<li><a class="reference" href="#value" id="id34" name="id34"><tt class="literal"><span class="pre">Value</span></tt></a></li>
<li><a class="reference" href="#categoryortraversal" id="id35" name="id35"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></li>
<li><a class="reference" href="#id10" id="id36" name="id36"><tt class="literal"><span class="pre">Reference</span></tt></a></li>
<li><a class="reference" href="#difference" id="id37" name="id37"><tt class="literal"><span class="pre">Difference</span></tt></a></li>
<li><a class="reference" href="#tutorial-example" id="id28" name="id28">Tutorial Example</a><ul>
<li><a class="reference" href="#the-problem" id="id29" name="id29">The Problem</a></li>
<li><a class="reference" href="#a-basic-iterator-using-iterator-facade" id="id30" name="id30">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
<li><a class="reference" href="#template-arguments-for-iterator-facade" id="id31" name="id31">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a><ul>
<li><a class="reference" href="#derived" id="id32" name="id32"><tt class="literal"><span class="pre">Derived</span></tt></a></li>
<li><a class="reference" href="#value" id="id33" name="id33"><tt class="literal"><span class="pre">Value</span></tt></a></li>
<li><a class="reference" href="#categoryortraversal" id="id34" name="id34"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></li>
<li><a class="reference" href="#id10" id="id35" name="id35"><tt class="literal"><span class="pre">Reference</span></tt></a></li>
<li><a class="reference" href="#difference" id="id36" name="id36"><tt class="literal"><span class="pre">Difference</span></tt></a></li>
</ul>
</li>
<li><a class="reference" href="#constructors-and-data-members" id="id38" name="id38">Constructors and Data Members</a></li>
<li><a class="reference" href="#implementing-the-core-operations" id="id39" name="id39">Implementing the Core Operations</a></li>
<li><a class="reference" href="#constructors-and-data-members" id="id37" name="id37">Constructors and Data Members</a></li>
<li><a class="reference" href="#implementing-the-core-operations" id="id38" name="id38">Implementing the Core Operations</a></li>
</ul>
</li>
<li><a class="reference" href="#a-constant-node-iterator" id="id40" name="id40">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></li>
<li><a class="reference" href="#interoperability" id="id41" name="id41">Interoperability</a></li>
<li><a class="reference" href="#telling-the-truth" id="id42" name="id42">Telling the Truth</a></li>
<li><a class="reference" href="#wrap-up" id="id43" name="id43">Wrap Up</a></li>
<li><a class="reference" href="#a-constant-node-iterator" id="id39" name="id39">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></li>
<li><a class="reference" href="#interoperability" id="id40" name="id40">Interoperability</a></li>
<li><a class="reference" href="#telling-the-truth" id="id41" name="id41">Telling the Truth</a></li>
<li><a class="reference" href="#wrap-up" id="id42" name="id42">Wrap Up</a></li>
</ul>
</li>
</ul>
@@ -290,7 +289,7 @@ public:
typedef Reference reference;
typedef Value* pointer;
typedef Difference difference_type;
typedef /* see <a class="reference" href="#facade-iterator-category">below</a> */ iterator_category;
typedef /* see <a class="reference" href="#iterator-category">below</a> */ iterator_category;
reference operator*() const;
/* see <a class="reference" href="#operator-arrow">below</a> */ operator-&gt;() const;
@@ -359,6 +358,39 @@ template &lt;class Derived, class V, class TC, class R, class D&gt;
Derived operator+ (iterator_facade&lt;Derived, V, TC, R, D&gt; const&amp;,
typename Derived::difference_type n)
</pre>
<a class="target" id="iterator-category" name="iterator-category"></a><p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member of <tt class="literal"><span class="pre">iterator_facade</span></tt> is
<tt class="literal"><span class="pre">facade_iterator_category(CategoryOrTraversal,</span> <span class="pre">value_type,</span>
<span class="pre">reference)</span></tt>, as specified by the following pseudo-code:</p>
<pre class="literal-block">
facade_iterator_category(C, V, R) =
if (C is convertible to input_iterator_tag or output_iterator_tag) then
return C
else if (C is convertible to incrementable_traversal_tag) then
if (R is a reference type
and C is convertible to forward_traversal_tag) then
if (C is convertible to random_access_traversal_tag)
return a type convertible to random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
return a type convertible to bidirectional_iterator_tag
else
return a type convertible to forward_iterator_tag
else if (C is convertible to single_pass_traversal_tag
and R is convertible to V)
return a type convertible to input_iterator_tag
else
return C
</pre>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
<p>If <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt> is <tt class="literal"><span class="pre">use_default</span></tt> then
<tt class="literal"><span class="pre">iterator_traversal&lt;Derived&gt;::type</span></tt> is convertible to the most
derived standard traversal tag type to which
<tt class="literal"><span class="pre">iterator_traversal&lt;Iterator&gt;::type</span></tt> is also convertible, and not to
any more-derived traversal tag type. Otherwise
<tt class="literal"><span class="pre">iterator_traversal&lt;Derived&gt;::type</span></tt> is convertible to the most
derived standard traversal tag type to which <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>
is also convertible, and not to any more-derived traversal tag type.</p>
<p>The <tt class="literal"><span class="pre">enable_if_interoperable</span></tt> template used above is for exposition
purposes. The member operators should be only be in an overload set
provided the derived types <tt class="literal"><span class="pre">Dr1</span></tt> and <tt class="literal"><span class="pre">Dr2</span></tt> are interoperable,
@@ -422,8 +454,7 @@ Iterator</td>
<tr><td><tt class="literal"><span class="pre">c.equal(y)</span></tt></td>
<td>convertible to bool</td>
<td>true iff <tt class="literal"><span class="pre">c</span></tt> and <tt class="literal"><span class="pre">y</span></tt> refer to the
same position. Implements <tt class="literal"><span class="pre">c</span> <span class="pre">==</span> <span class="pre">y</span></tt>
and <tt class="literal"><span class="pre">c</span> <span class="pre">!=</span> <span class="pre">y</span></tt>.</td>
same position.</td>
<td>Single Pass Iterator</td>
</tr>
<tr><td><tt class="literal"><span class="pre">a.increment()</span></tt></td>
@@ -443,77 +474,19 @@ Iterator</td>
<td>Random Access Traversal
Iterator</td>
</tr>
<tr><td><tt class="literal"><span class="pre">c.distance_to(b)</span></tt></td>
<td>convertible to
<tt class="literal"><span class="pre">F::difference_type</span></tt></td>
<td>equivalent to <tt class="literal"><span class="pre">distance(c,</span> <span class="pre">b)</span></tt></td>
<td>Random Access Traversal
Iterator</td>
</tr>
<tr><td><tt class="literal"><span class="pre">c.distance_to(z)</span></tt></td>
<td>convertible to
<tt class="literal"><span class="pre">F::difference_type</span></tt></td>
<td>equivalent to <tt class="literal"><span class="pre">distance(c,</span> <span class="pre">z)</span></tt>.
Implements <tt class="literal"><span class="pre">c</span> <span class="pre">-</span> <span class="pre">z</span></tt>, <tt class="literal"><span class="pre">c</span> <span class="pre">&lt;</span> <span class="pre">z</span></tt>, <tt class="literal"><span class="pre">c</span>
<span class="pre">&lt;=</span> <span class="pre">z</span></tt>, <tt class="literal"><span class="pre">c</span> <span class="pre">&gt;</span> <span class="pre">z</span></tt>, and <tt class="literal"><span class="pre">c</span> <span class="pre">&gt;=</span> <span class="pre">c</span></tt>.</td>
<td>equivalent to <tt class="literal"><span class="pre">distance(c,</span> <span class="pre">X(z))</span></tt>.</td>
<td>Random Access Traversal
Iterator</td>
</tr>
</tbody>
</table>
</div>
<a class="target" id="facade-iterator-category" name="facade-iterator-category"></a></div>
<div class="section" id="iterator-facade-iterator-category">
<h2><a class="toc-backref" href="#id27" name="iterator-facade-iterator-category"><tt class="literal"><span class="pre">iterator_facade</span></tt> iterator category</a></h2>
<p>The <tt class="literal"><span class="pre">iterator_category</span></tt> member of <tt class="literal"><span class="pre">iterator_facade&lt;X,V,R,C,D&gt;</span></tt>
satisfies the following conditions:</p>
<ul>
<li><p class="first">if <tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::input_iterator_tag</span></tt> or
<tt class="literal"><span class="pre">C</span></tt> is convertible to <tt class="literal"><span class="pre">std::output_iterator_tag</span></tt>,
<tt class="literal"><span class="pre">iterator_category</span></tt> is the same as <tt class="literal"><span class="pre">C</span></tt>.</p>
</li>
<li><p class="first">Otherwise, if <tt class="literal"><span class="pre">C</span></tt> is not convertible to
<tt class="literal"><span class="pre">incrementable_traversal_tag</span></tt>, the program is ill-formed</p>
</li>
<li><p class="first">Otherwise:</p>
<ul>
<li><p class="first"><tt class="literal"><span class="pre">iterator_category</span></tt> is convertible to the iterator
category tag or tags given by the following algorithm, and
not to any more-derived iterator category tag or tags:</p>
<pre class="literal-block">
if (R is a reference type
&amp;&amp; C is convertible to forward_traversal_tag)
{
if (C is convertible to random_access_traversal_tag)
random_access_iterator_tag
else if (C is convertible to bidirectional_traversal_tag)
bidirectional_iterator_tag
else
forward_iterator_tag
}
else
{
if (C is convertible to single_pass_traversal_tag
&amp;&amp; R is convertible to V)
input_iterator_tag
else
C
}
</pre>
</li>
<li><p class="first"><tt class="literal"><span class="pre">iterator_traversal&lt;X&gt;::type</span></tt> is convertible to the most
derived traversal tag type to which <tt class="literal"><span class="pre">C</span></tt> is also
convertible, and not to any more-derived traversal tag type.</p>
</li>
</ul>
</li>
</ul>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
</div>
<div class="section" id="iterator-facade-operations">
<h2><a class="toc-backref" href="#id28" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h2>
<h2><a class="toc-backref" href="#id27" name="iterator-facade-operations"><tt class="literal"><span class="pre">iterator_facade</span></tt> operations</a></h2>
<p>The operations in this section are described in terms of operations on
the core interface of <tt class="literal"><span class="pre">Derived</span></tt> which may be inaccessible
(i.e. private). The implementation should access these operations
@@ -551,11 +524,10 @@ of type <tt class="literal"><span class="pre">pointer</span></tt> equal to:</p>
<tbody valign="top">
<tr class="field"><th class="field-name">Returns:</th><td class="field-body">an object convertible to <tt class="literal"><span class="pre">value_type</span></tt>. For constant
objects <tt class="literal"><span class="pre">v</span></tt> of type <tt class="literal"><span class="pre">value_type</span></tt>, and <tt class="literal"><span class="pre">n</span></tt> of type
<tt class="literal"><span class="pre">difference_type</span></tt>, and reference <tt class="literal"><span class="pre">p</span></tt> equal to
<tt class="literal"><span class="pre">*static_cast&lt;Derived</span> <span class="pre">const*&gt;(this)</span></tt>, <tt class="literal"><span class="pre">(*this)[n]</span> <span class="pre">=</span> <span class="pre">v</span></tt> is
equivalent to <tt class="literal"><span class="pre">*(p+</span> <span class="pre">n)</span> <span class="pre">=</span> <span class="pre">v</span></tt>, and <tt class="literal"><span class="pre">static_cast&lt;value_type</span>
<tt class="literal"><span class="pre">difference_type</span></tt>, <tt class="literal"><span class="pre">(*this)[n]</span> <span class="pre">=</span> <span class="pre">v</span></tt> is equivalent to
<tt class="literal"><span class="pre">*(*this</span> <span class="pre">+</span> <span class="pre">n)</span> <span class="pre">=</span> <span class="pre">v</span></tt>, and <tt class="literal"><span class="pre">static_cast&lt;value_type</span>
<span class="pre">const&amp;&gt;((*this)[n])</span></tt> is equivalent to
<tt class="literal"><span class="pre">static_cast&lt;value_type</span> <span class="pre">const&amp;&gt;(*(p+n))</span></tt></td>
<tt class="literal"><span class="pre">static_cast&lt;value_type</span> <span class="pre">const&amp;&gt;(*(*this</span> <span class="pre">+</span> <span class="pre">n))</span></tt></td>
</tr>
</tbody>
</table>
@@ -655,7 +627,7 @@ return tmp -= n;
</div>
</div>
<div class="section" id="tutorial-example">
<h1><a class="toc-backref" href="#id29" name="tutorial-example">Tutorial Example</a></h1>
<h1><a class="toc-backref" href="#id28" name="tutorial-example">Tutorial Example</a></h1>
<!-- Copyright David Abrahams 2004. Use, modification and distribution is -->
<!-- subject to the Boost Software License, Version 1.0. (See accompanying -->
<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) -->
@@ -665,7 +637,7 @@ example of a linked list of polymorphic objects. This example was
inspired by a <a class="reference" href="http://thread.gmane.org/gmane.comp.lib.boost.user/5100">posting</a> by Keith Macdonald on the <a class="reference" href="../../../more/mailing_lists.htm#users">Boost-Users</a>
mailing list.</p>
<div class="section" id="the-problem">
<h2><a class="toc-backref" href="#id30" name="the-problem">The Problem</a></h2>
<h2><a class="toc-backref" href="#id29" name="the-problem">The Problem</a></h2>
<p>Say we've written a polymorphic linked list node base class:</p>
<pre class="literal-block">
# include &lt;iostream&gt;
@@ -727,7 +699,7 @@ inline std::ostream&amp; operator&lt;&lt;(std::ostream&amp; s, node_base const&a
lists.</p>
</div>
<div class="section" id="a-basic-iterator-using-iterator-facade">
<h2><a class="toc-backref" href="#id31" name="a-basic-iterator-using-iterator-facade">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h2>
<h2><a class="toc-backref" href="#id30" name="a-basic-iterator-using-iterator-facade">A Basic Iterator Using <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h2>
<p>We will construct a <tt class="literal"><span class="pre">node_iterator</span></tt> class using inheritance from
<tt class="literal"><span class="pre">iterator_facade</span></tt> to implement most of the iterator's operations.</p>
<pre class="literal-block">
@@ -741,24 +713,24 @@ class node_iterator
};
</pre>
<div class="section" id="template-arguments-for-iterator-facade">
<h3><a class="toc-backref" href="#id32" name="template-arguments-for-iterator-facade">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h3>
<h3><a class="toc-backref" href="#id31" name="template-arguments-for-iterator-facade">Template Arguments for <tt class="literal"><span class="pre">iterator_facade</span></tt></a></h3>
<p><tt class="literal"><span class="pre">iterator_facade</span></tt> has several template parameters, so we must decide
what types to use for the arguments. The parameters are <tt class="literal"><span class="pre">Derived</span></tt>,
<tt class="literal"><span class="pre">Value</span></tt>, <tt class="literal"><span class="pre">CategoryOrTraversal</span></tt>, <tt class="literal"><span class="pre">Reference</span></tt>, and <tt class="literal"><span class="pre">Difference</span></tt>.</p>
<div class="section" id="derived">
<h4><a class="toc-backref" href="#id33" name="derived"><tt class="literal"><span class="pre">Derived</span></tt></a></h4>
<h4><a class="toc-backref" href="#id32" name="derived"><tt class="literal"><span class="pre">Derived</span></tt></a></h4>
<p>Because <tt class="literal"><span class="pre">iterator_facade</span></tt> is meant to be used with the CRTP
<a class="citation-reference" href="#cop95" id="id8" name="id8">[Cop95]</a> the first parameter is the iterator class name itself,
<tt class="literal"><span class="pre">node_iterator</span></tt>.</p>
</div>
<div class="section" id="value">
<h4><a class="toc-backref" href="#id34" name="value"><tt class="literal"><span class="pre">Value</span></tt></a></h4>
<h4><a class="toc-backref" href="#id33" name="value"><tt class="literal"><span class="pre">Value</span></tt></a></h4>
<p>The <tt class="literal"><span class="pre">Value</span></tt> parameter determines the <tt class="literal"><span class="pre">node_iterator</span></tt>'s
<tt class="literal"><span class="pre">value_type</span></tt>. In this case, we are iterating over <tt class="literal"><span class="pre">node_base</span></tt>
objects, so <tt class="literal"><span class="pre">Value</span></tt> will be <tt class="literal"><span class="pre">node_base</span></tt>.</p>
</div>
<div class="section" id="categoryortraversal">
<h4><a class="toc-backref" href="#id35" name="categoryortraversal"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></h4>
<h4><a class="toc-backref" href="#id34" name="categoryortraversal"><tt class="literal"><span class="pre">CategoryOrTraversal</span></tt></a></h4>
<p>Now we have to determine which <a class="reference" href="new-iter-concepts.html#iterator-traversal-concepts-lib-iterator-traversal">iterator traversal concept</a> our
<tt class="literal"><span class="pre">node_iterator</span></tt> is going to model. Singly-linked lists only have
forward links, so our iterator can't can't be a <a class="reference" href="new-iter-concepts.html#bidirectional-traversal-iterators-lib-bidirectional-traversal-iterators">bidirectional
@@ -778,7 +750,7 @@ end up being <tt class="literal"><span class="pre">std::forward_iterator_tag</sp
</table>
</div>
<div class="section" id="id10">
<h4><a class="toc-backref" href="#id36" name="id10"><tt class="literal"><span class="pre">Reference</span></tt></a></h4>
<h4><a class="toc-backref" href="#id35" name="id10"><tt class="literal"><span class="pre">Reference</span></tt></a></h4>
<p>The <tt class="literal"><span class="pre">Reference</span></tt> argument becomes the type returned by
<tt class="literal"><span class="pre">node_iterator</span></tt>'s dereference operation, and will also be the
same as <tt class="literal"><span class="pre">std::iterator_traits&lt;node_iterator&gt;::reference</span></tt>. The
@@ -787,7 +759,7 @@ library's default for this parameter is <tt class="literal"><span class="pre">Va
type, we can omit this argument, or pass <tt class="literal"><span class="pre">use_default</span></tt>.</p>
</div>
<div class="section" id="difference">
<h4><a class="toc-backref" href="#id37" name="difference"><tt class="literal"><span class="pre">Difference</span></tt></a></h4>
<h4><a class="toc-backref" href="#id36" name="difference"><tt class="literal"><span class="pre">Difference</span></tt></a></h4>
<p>The <tt class="literal"><span class="pre">Difference</span></tt> argument determines how the distance between
two <tt class="literal"><span class="pre">node_iterator</span></tt>s will be measured and will also be the
same as <tt class="literal"><span class="pre">std::iterator_traits&lt;node_iterator&gt;::difference_type</span></tt>.
@@ -814,7 +786,7 @@ class node_iterator
</div>
</div>
<div class="section" id="constructors-and-data-members">
<h3><a class="toc-backref" href="#id38" name="constructors-and-data-members">Constructors and Data Members</a></h3>
<h3><a class="toc-backref" href="#id37" name="constructors-and-data-members">Constructors and Data Members</a></h3>
<p>Next we need to decide how to represent the iterator's position.
This representation will take the form of data members, so we'll
also need to write constructors to initialize them. The
@@ -859,7 +831,7 @@ default constructor to leave <tt class="literal"><span class="pre">m_node</span>
</table>
</div>
<div class="section" id="implementing-the-core-operations">
<h3><a class="toc-backref" href="#id39" name="implementing-the-core-operations">Implementing the Core Operations</a></h3>
<h3><a class="toc-backref" href="#id38" name="implementing-the-core-operations">Implementing the Core Operations</a></h3>
<p>The last step is to implement the <a class="reference" href="#core-operations">core operations</a> required by
the concepts we want our iterator to model. Referring to the
<a class="reference" href="#core-operations">table</a>, we can see that the first three rows are applicable
@@ -910,7 +882,7 @@ iterator! For a working example of its use, see <a class="reference" href="../e
</div>
</div>
<div class="section" id="a-constant-node-iterator">
<h2><a class="toc-backref" href="#id40" name="a-constant-node-iterator">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></h2>
<h2><a class="toc-backref" href="#id39" name="a-constant-node-iterator">A constant <tt class="literal"><span class="pre">node_iterator</span></tt></a></h2>
<div class="sidebar">
<p class="sidebar-title">Constant and Mutable iterators</p>
<p>The term <strong>mutable iterator</strong> means an iterator through which
@@ -1011,7 +983,7 @@ typedef node_iter&lt;node_base const&gt; node_const_iterator;
</pre>
</div>
<div class="section" id="interoperability">
<h2><a class="toc-backref" href="#id41" name="interoperability">Interoperability</a></h2>
<h2><a class="toc-backref" href="#id40" name="interoperability">Interoperability</a></h2>
<p>Our <tt class="literal"><span class="pre">const_node_iterator</span></tt> works perfectly well on its own, but
taken together with <tt class="literal"><span class="pre">node_iterator</span></tt> it doesn't quite meet
expectations. For example, we'd like to be able to pass a
@@ -1084,7 +1056,7 @@ traversal iterator</a>, we'd have had to templatize its
iterators <a class="reference" href="../example/node_iterator2.cpp">here</a>.</p>
</div>
<div class="section" id="telling-the-truth">
<h2><a class="toc-backref" href="#id42" name="telling-the-truth">Telling the Truth</a></h2>
<h2><a class="toc-backref" href="#id41" name="telling-the-truth">Telling the Truth</a></h2>
<p>Now <tt class="literal"><span class="pre">node_iterator</span></tt> and <tt class="literal"><span class="pre">node_const_iterator</span></tt> behave exactly as
you'd expect... almost. We can compare them and we can convert in
one direction: from <tt class="literal"><span class="pre">node_iterator</span></tt> to <tt class="literal"><span class="pre">node_const_iterator</span></tt>.
@@ -1122,7 +1094,7 @@ appropriate:</p>
</pre>
</div>
<div class="section" id="wrap-up">
<h2><a class="toc-backref" href="#id43" name="wrap-up">Wrap Up</a></h2>
<h2><a class="toc-backref" href="#id42" name="wrap-up">Wrap Up</a></h2>
<p>This concludes our <tt class="literal"><span class="pre">iterator_facade</span></tt> tutorial, but before you
stop reading we urge you to take a look at <a class="reference" href="iterator_adaptor.html"><tt class="literal"><span class="pre">iterator_adaptor</span></tt></a>.
There's another way to approach writing these iterators which might
doc/iterator_facade_ref.rst
+19 -10
View File
@@ -89,13 +89,30 @@
Derived operator+ (iterator_facade<Derived, V, TC, R, D> const&,
typename Derived::difference_type n)
__ `facade iterator category`_
__ `iterator category`_
__ `operator arrow`_
__ brackets_
.. _`iterator category`:
The ``iterator_category`` member of ``iterator_facade`` is
``facade_iterator_category(CategoryOrTraversal, value_type,
reference)``, as specified by the following pseudo-code:
.. include:: facade_iterator_category.rst
If ``CategoryOrTraversal`` is ``use_default`` then
``iterator_traversal<Derived>::type`` is convertible to the most
derived standard traversal tag type to which
``iterator_traversal<Iterator>::type`` is also convertible, and not to
any more-derived traversal tag type. Otherwise
``iterator_traversal<Derived>::type`` is convertible to the most
derived standard traversal tag type to which ``CategoryOrTraversal``
is also convertible, and not to any more-derived traversal tag type.
The ``enable_if_interoperable`` template used above is for exposition
purposes. The member operators should be only be in an overload set
provided the derived types ``Dr1`` and ``Dr2`` are interoperable,
@@ -162,15 +179,7 @@ interoperable with ``X``.
| |``F::difference_type``| |Iterator |
+--------------------+----------------------+-------------------------------------+---------------------------+
.. _facade iterator category:
``iterator_facade`` iterator category
-------------------------------------
The ``iterator_category`` member of ``iterator_facade<X,V,R,C,D>``
satisfies the following conditions:
.. include:: facade_iterator_category.rst
``iterator_facade`` operations
------------------------------
doc/new-iter-concepts.html
+3 -6
View File
@@ -373,9 +373,9 @@ the stated semantics. <tt class="literal"><span class="pre">U</span></tt> is the
type <tt class="literal"><span class="pre">T</span></tt>.</p>
<table border class="table">
<colgroup>
<col width="30%" />
<col width="28%" />
<col width="20%" />
<col width="50%" />
<col width="52%" />
</colgroup>
<thead valign="bottom">
<tr><th colspan="3">Readable Iterator Requirements (in addition to Assignable and Copy Constructible)</th>
@@ -401,10 +401,7 @@ non-cv-qualified type</td>
</tr>
<tr><td><tt class="literal"><span class="pre">a-&gt;m</span></tt></td>
<td><tt class="literal"><span class="pre">U&amp;</span></tt></td>
<td>pre: <tt class="literal"><span class="pre">static_cast&lt;T</span> <span class="pre">const&amp;&gt;(*a).m</span></tt> is well-defined. If
<tt class="literal"><span class="pre">static_cast&lt;T&amp;&gt;(*a).m</span></tt> is well-defined, equivalent to
<tt class="literal"><span class="pre">static_cast&lt;T&amp;&gt;(*a).m</span></tt>; otherwise, equivalent to
<tt class="literal"><span class="pre">static_cast&lt;T</span> <span class="pre">const&amp;&gt;(*a).m</span></tt>.</td>
<td>pre: <tt class="literal"><span class="pre">pre:</span> <span class="pre">(*a).m</span></tt> is well-defined. Equivalent to <tt class="literal"><span class="pre">(*a).m</span></tt>.</td>
</tr>
</tbody>
</table>
doc/new-iter-concepts.rst
+13 -16
View File
@@ -367,22 +367,19 @@ Copy Constructible, the following expressions are valid and respect
the stated semantics. ``U`` is the type of any specified member of
type ``T``.
+------------------------------------------------------------------------------------------------------------------------+
|Readable Iterator Requirements (in addition to Assignable and Copy Constructible) |
+-----------------------------------+------------------------+-----------------------------------------------------------+
|Expression |Return Type |Note/Precondition |
+===================================+========================+===========================================================+
|``iterator_traits<X>::value_type`` |``T`` |Any non-reference, |
| | |non-cv-qualified type |
+-----------------------------------+------------------------+-----------------------------------------------------------+
|``*a`` | Convertible to ``T`` |pre: ``a`` is dereferenceable. If ``a == b`` then ``*a`` |
| | | is equivalent to ``*b``. |
+-----------------------------------+------------------------+-----------------------------------------------------------+
|``a->m`` |``U&`` |pre: ``static_cast<T const&>(*a).m`` is well-defined. If |
| | |``static_cast<T&>(*a).m`` is well-defined, equivalent to |
| | |``static_cast<T&>(*a).m``; otherwise, equivalent to |
| | |``static_cast<T const&>(*a).m``. |
+-----------------------------------+------------------------+-----------------------------------------------------------+
+-----------------------------------------------------------------------------------------------------------------------------+
|Readable Iterator Requirements (in addition to Assignable and Copy Constructible) |
+-----------------------------------+------------------------+----------------------------------------------------------------+
|Expression |Return Type |Note/Precondition |
+===================================+========================+================================================================+
|``iterator_traits<X>::value_type`` |``T`` |Any non-reference, |
| | |non-cv-qualified type |
+-----------------------------------+------------------------+----------------------------------------------------------------+
|``*a`` | Convertible to ``T`` |pre: ``a`` is dereferenceable. If ``a == b`` then ``*a`` |
| | | is equivalent to ``*b``. |
+-----------------------------------+------------------------+----------------------------------------------------------------+
|``a->m`` |``U&`` |pre: ``pre: (*a).m`` is well-defined. Equivalent to ``(*a).m``. |
+-----------------------------------+------------------------+----------------------------------------------------------------+
.. We won't say anything about iterator_traits<X>::reference until the DR is resolved. -JGS