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<a name="range.reference.adaptors.reference.type_erased"></a><a class="link" href="type_erased.html" title="type_erased">type_erased</a>
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-<div class="toc"><dl><dt><span class="section"><a href="type_erased.html#range.reference.adaptors.reference.type_erased.type_erased_example">type-erased
+<div class="toc"><dl
class="toc"><dt><span class="section"><a href="type_erased.html#range.reference.adaptors.reference.type_erased.type_erased_example">type-erased
example</a></span></dt></dl></div>
<div class="informaltable"><table class="table">
<colgroup>
Let <code class="computeroutput"><span class="identifier">Rng</span></code> be the type of
<code class="computeroutput"><span class="identifier">rng</span></code>.
</p>
-<div class="itemizedlist"><ul class="itemizedlist" type="disc">
+<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
-<p class="simpara">
<span class="bold"><strong>Template parameters:</strong></span>
- </p>
-<div class="itemizedlist"><ul class="itemizedlist" type="circle">
+ <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
- <code class="computeroutput"><span class="identifier">Value</span></code> is the
- <code class="computeroutput"><span class="identifier">value_type</span></code> for
- the <code class="computeroutput"><span class="identifier">any_range</span></code>.
- If this is set to boost::use_default, <code class="computeroutput"><span class="identifier">Value</span></code>
- will be calculated from the range type when the adaptor is applied.
- </li>
+ <code class="computeroutput"><span class="identifier">Value</span></code> is the
+ <code class="computeroutput"><span class="identifier">value_type</span></code>
+ for the <code class="computeroutput"><span class="identifier">any_range</span></code>.
+ If this is set to boost::use_default, <code class="computeroutput"><span class="identifier">Value</span></code>
+ will be calculated from the range type when the adaptor is
+ applied.
+ </li>
<li class="listitem">
- <code class="computeroutput"><span class="identifier">Traversal</span></code> is
- the tag used to identify the traversal of the resultant range.
- Frequently it is desireable to set a traversal category lower
- than the source container or range to maximize the number of
- ranges that can convert to the <code class="computeroutput"><span class="identifier">any_range</span></code>.
- If this is left as boost::use_default then <code class="computeroutput"><span class="identifier">Traversal</span></code>
- will be <code class="computeroutput"><span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">iterator_traversal</span><span class="special"><</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_iterator</span><span class="special"><</span><span class="identifier">Rng</span><span class="special">>::</span><span class="identifier">type</span><span class="special">>::</span><span class="identifier">type</span></code>
- </li>
+ <code class="computeroutput"><span class="identifier">Traversal</span></code> is
+ the tag used to identify the traversal of the resultant range.
+ Frequently it is desirable to set a traversal category lower
+ than the source container or range to maximize the number of
+ ranges that can convert to the <code class="computeroutput"><span class="identifier">any_range</span></code>.
+ If this is left as boost::use_default then <code class="computeroutput"><span class="identifier">Traversal</span></code>
+ will be <code class="computeroutput"><span class="keyword">typename</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">iterator_traversal</span><span class="special"><</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_iterator</span><span class="special"><</span><span class="identifier">Rng</span><span class="special">>::</span><span class="identifier">type</span><span class="special">>::</span><span class="identifier">type</span></code>
+ </li>
<li class="listitem">
- <code class="computeroutput"><span class="identifier">Reference</span></code> is
- the <code class="computeroutput"><span class="identifier">reference</span></code>
- for the <code class="computeroutput"><span class="identifier">any_range</span></code>.
- <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">use_default</span></code> will equate to
- <code class="computeroutput"><span class="keyword">typename</span> <span class="identifier">range_reference</span><span class="special"><</span><span class="identifier">Rng</span><span class="special">>::</span><span class="identifier">type</span></code>.
- </li>
+ <code class="computeroutput"><span class="identifier">Reference</span></code> is
+ the <code class="computeroutput"><span class="identifier">reference</span></code>
+ for the <code class="computeroutput"><span class="identifier">any_range</span></code>.
+ <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">use_default</span></code> will equate to
+ <code class="computeroutput"><span class="keyword">typename</span> <span class="identifier">range_reference</span><span class="special"><</span><span class="identifier">Rng</span><span class="special">>::</span><span class="identifier">type</span></code>.
+ </li>
<li class="listitem">
- <code class="computeroutput"><span class="identifier">Difference</span></code> is
- the <code class="computeroutput"><span class="identifier">difference_type</span></code>
- for the any_range. <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">use_default</span></code>
- will equate to <code class="computeroutput"><span class="keyword">typename</span>
- <span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_difference</span><span class="special"><</span><span class="identifier">Rng</span><span class="special">>::</span><span class="identifier">type</span></code>
- </li>
+ <code class="computeroutput"><span class="identifier">Difference</span></code>
+ is the <code class="computeroutput"><span class="identifier">difference_type</span></code>
+ for the any_range. <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">use_default</span></code>
+ will equate to <code class="computeroutput"><span class="keyword">typename</span>
+ <span class="identifier">boost</span><span class="special">::</span><span class="identifier">range_difference</span><span class="special"><</span><span class="identifier">Rng</span><span class="special">>::</span><span class="identifier">type</span></code>
+ </li>
<li class="listitem">
- <code class="computeroutput"><span class="identifier">Buffer</span></code> is the
- storage used to allocate the underlying iterator wrappers. This
- can typically be ignored, but is available as a template parameter
- for customization. Buffer must be a model of the <code class="computeroutput"><span class="identifier">AnyIteratorBufferConcept</span></code>.
- </li>
+ <code class="computeroutput"><span class="identifier">Buffer</span></code> is the
+ storage used to allocate the underlying iterator wrappers.
+ This can typically be ignored, but is available as a template
+ parameter for customization. Buffer must be a model of the
+ <code class="computeroutput"><span class="identifier">AnyIteratorBufferConcept</span></code>.
+ </li>
</ul></div>
-</li>
+ </li>
<li class="listitem">
<span class="bold"><strong>Precondition:</strong></span> <code class="computeroutput"><span class="identifier">Traversal</span></code>
is one of <code class="computeroutput"><span class="special">{</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">use_default</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">single_pass_traversal_tag</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">forward_traversal_tag</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">bidirectional_traversal_tag</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">random_access_traversal_tag</span>
otherwise <code class="computeroutput"><span class="identifier">Traversal</span></code>.
</li>
</ul></div>
-<a name="range.reference.adaptors.reference.type_erased.anyiteratorbufferconcept"></a><h6>
-<a name="id677095"></a>
- <a class="link" href="type_erased.html#range.reference.adaptors.reference.type_erased.anyiteratorbufferconcept">AnyIteratorBufferConcept</a>
+<h6>
+<a name="range.reference.adaptors.reference.type_erased.h0"></a>
+ <span class="phrase"><a name="range.reference.adaptors.reference.type_erased.anyiteratorbufferconcept"></a></span><a class="link" href="type_erased.html#range.reference.adaptors.reference.type_erased.anyiteratorbufferconcept">AnyIteratorBufferConcept</a>
</h6>
<p>
-
</p>
<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">AnyIteratorBufferConcept</span>
<span class="special">{</span>
<span class="identifier">AnyIteratorBufferConcept</span><span class="special">();</span>
<span class="special">~</span><span class="identifier">AnyIteratorBufferConcept</span><span class="special">();</span>
- <span class="comment">// bytes is the requested size to allocate. This function
-</span> <span class="comment">// must return a pointer to an adequate area of memory.
-</span> <span class="comment">// throws: bad_alloc
-</span> <span class="comment">//
-</span> <span class="comment">// The buffer will only ever have zero or one
-</span> <span class="comment">// outstanding memory allocations.
-</span> <span class="keyword">void</span><span class="special">*</span> <span class="identifier">allocate</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes</span><span class="special">);</span>
+ <span class="comment">// bytes is the requested size to allocate. This function</span>
+ <span class="comment">// must return a pointer to an adequate area of memory.</span>
+ <span class="comment">// throws: bad_alloc</span>
+ <span class="comment">//</span>
+ <span class="comment">// The buffer will only ever have zero or one</span>
+ <span class="comment">// outstanding memory allocations.</span>
+ <span class="keyword">void</span><span class="special">*</span> <span class="identifier">allocate</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes</span><span class="special">);</span>
- <span class="comment">// deallocate this buffer
-</span> <span class="keyword">void</span> <span class="identifier">deallocate</span><span class="special">();</span>
+ <span class="comment">// deallocate this buffer</span>
+ <span class="keyword">void</span> <span class="identifier">deallocate</span><span class="special">();</span>
<span class="special">};</span>
</pre>
<p>
example</a>
</h6></div></div></div>
<p>
-
</p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">range</span><span class="special">/</span><span class="identifier">adaptor</span><span class="special">/</span><span class="identifier">type_erased</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">range</span><span class="special">/</span><span class="identifier">algorithm</span><span class="special">/</span><span class="identifier">copy</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">assign</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">foreach</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
-<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">algorithm</span><span class="special">></span>
+<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iterator</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">iostream</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">list</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">vector</span><span class="special">></span>
-<span class="comment">// The client interface from an OO perspective merely requires a sequence
-</span><span class="comment">// of integers that can be forward traversed
-</span><span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">any_range</span><span class="special"><</span>
+<span class="comment">// The client interface from an OO perspective merely requires a sequence</span>
+<span class="comment">// of integers that can be forward traversed</span>
+<span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">any_range</span><span class="special"><</span>
<span class="keyword">int</span>
<span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">forward_traversal_tag</span>
<span class="special">,</span> <span class="keyword">int</span>
<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">assign</span><span class="special">;</span>
<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">;</span>
- <span class="comment">// Under most conditions one would simply use an appropriate
-</span> <span class="comment">// any_range as a function parameter. The type_erased adaptor
-</span> <span class="comment">// is often superfluous. However because the type_erased
-</span> <span class="comment">// adaptor is applied to a range, we can use default template
-</span> <span class="comment">// arguments that are generated in conjunction with the
-</span> <span class="comment">// range type to which we are applying the adaptor.
-</span>
+ <span class="comment">// Under most conditions one would simply use an appropriate</span>
+ <span class="comment">// any_range as a function parameter. The type_erased adaptor</span>
+ <span class="comment">// is often superfluous. However because the type_erased</span>
+ <span class="comment">// adaptor is applied to a range, we can use default template</span>
+ <span class="comment">// arguments that are generated in conjunction with the</span>
+ <span class="comment">// range type to which we are applying the adaptor.</span>
+
<span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span><span class="keyword">int</span><span class="special">></span> <span class="identifier">input</span><span class="special">;</span>
<span class="identifier">input</span> <span class="special">+=</span> <span class="number">1</span><span class="special">,</span><span class="number">2</span><span class="special">,</span><span class="number">3</span><span class="special">,</span><span class="number">4</span><span class="special">,</span><span class="number">5</span><span class="special">;</span>
- <span class="comment">// Note that this call is to a non-template function
-</span> <span class="identifier">server</span><span class="special">::</span><span class="identifier">display_integers</span><span class="special">(</span><span class="identifier">input</span><span class="special">);</span>
+ <span class="comment">// Note that this call is to a non-template function</span>
+ <span class="identifier">server</span><span class="special">::</span><span class="identifier">display_integers</span><span class="special">(</span><span class="identifier">input</span><span class="special">);</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">list</span><span class="special"><</span><span class="keyword">int</span><span class="special">></span> <span class="identifier">input2</span><span class="special">;</span>
<span class="identifier">input2</span> <span class="special">+=</span> <span class="number">6</span><span class="special">,</span><span class="number">7</span><span class="special">,</span><span class="number">8</span><span class="special">,</span><span class="number">9</span><span class="special">,</span><span class="number">10</span><span class="special">;</span>
- <span class="comment">// Note that this call is to the same non-tempate function
-</span> <span class="identifier">server</span><span class="special">::</span><span class="identifier">display_integers</span><span class="special">(</span><span class="identifier">input2</span><span class="special">);</span>
+ <span class="comment">// Note that this call is to the same non-tempate function</span>
+ <span class="identifier">server</span><span class="special">::</span><span class="identifier">display_integers</span><span class="special">(</span><span class="identifier">input2</span><span class="special">);</span>
<span class="identifier">input2</span><span class="special">.</span><span class="identifier">clear</span><span class="special">();</span>
<span class="identifier">input2</span> <span class="special">+=</span> <span class="number">11</span><span class="special">,</span><span class="number">12</span><span class="special">,</span><span class="number">13</span><span class="special">,</span><span class="number">14</span><span class="special">,</span><span class="number">15</span><span class="special">;</span>
- <span class="comment">// Calling using the adaptor looks like this:
-</span> <span class="comment">// Notice that here I have a type_erased that would be a
-</span> <span class="comment">// bidirectional_traversal_tag, but this is convertible
-</span> <span class="comment">// to the forward_traversal_tag equivalent hence this
-</span> <span class="comment">// works.
-</span> <span class="identifier">server</span><span class="special">::</span><span class="identifier">display_integers</span><span class="special">(</span><span class="identifier">input2</span> <span class="special">|</span> <span class="identifier">type_erased</span><span class="special"><>());</span>
+ <span class="comment">// Calling using the adaptor looks like this:</span>
+ <span class="comment">// Notice that here I have a type_erased that would be a</span>
+ <span class="comment">// bidirectional_traversal_tag, but this is convertible</span>
+ <span class="comment">// to the forward_traversal_tag equivalent hence this</span>
+ <span class="comment">// works.</span>
+ <span class="identifier">server</span><span class="special">::</span><span class="identifier">display_integers</span><span class="special">(</span><span class="identifier">input2</span> <span class="special">|</span> <span class="identifier">type_erased</span><span class="special"><>());</span>
- <span class="comment">// However we may simply wish to define an adaptor that
-</span> <span class="comment">// takes a range and makes it into an appropriate
-</span> <span class="comment">// forward_traversal any_range...
-</span> <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">type_erased</span><span class="special"><</span>
+ <span class="comment">// However we may simply wish to define an adaptor that</span>
+ <span class="comment">// takes a range and makes it into an appropriate</span>
+ <span class="comment">// forward_traversal any_range...</span>
+ <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">adaptors</span><span class="special">::</span><span class="identifier">type_erased</span><span class="special"><</span>
<span class="identifier">boost</span><span class="special">::</span><span class="identifier">use_default</span>
<span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">forward_traversal_tag</span>
<span class="special">></span> <span class="identifier">type_erased_forward</span><span class="special">;</span>
- <span class="comment">// This adaptor can turn other containers with different
-</span> <span class="comment">// value_types and reference_types into the appropriate
-</span> <span class="comment">// any_range.
-</span>
+ <span class="comment">// This adaptor can turn other containers with different</span>
+ <span class="comment">// value_types and reference_types into the appropriate</span>
+ <span class="comment">// any_range.</span>
+
<span class="identifier">server</span><span class="special">::</span><span class="identifier">display_integers</span><span class="special">(</span><span class="identifier">input2</span> <span class="special">|</span> <span class="identifier">type_erased_forward</span><span class="special">());</span>
<span class="special">}</span>
<span class="special">}</span>
</p>
</div>
<p>
- This would produce the output:
+ This would produce the output:
</p>
-<pre class="programlisting"><span class="number">1</span><span class="special">,</span><span class="number">2</span><span class="special">,</span><span class="number">3</span><span class="special">,</span><span class="number">4</span><span class="special">,</span><span class="number">5</span>
-<span class="number">6</span><span class="special">,</span><span class="number">7</span><span class="special">,</span><span class="number">8</span><span class="special">,</span><span class="number">9</span><span class="special">,</span><span class="number">10</span>
-<span class="number">11</span><span class="special">,</span><span class="number">12</span><span class="special">,</span><span class="number">13</span><span class="special">,</span><span class="number">14</span><span class="special">,</span><span class="number">15</span>
-<span class="number">11</span><span class="special">,</span><span class="number">12</span><span class="special">,</span><span class="number">13</span><span class="special">,</span><span class="number">14</span><span class="special">,</span><span class="number">15</span>
+<pre class="programlisting"><span class="number">1</span><span class="special">,</span><span class="number">2</span><span class="special">,</span><span class="number">3</span><span class="special">,</span><span class="number">4</span><span class="special">,</span><span class="number">5</span><span class="special">,</span>
+<span class="number">6</span><span class="special">,</span><span class="number">7</span><span class="special">,</span><span class="number">8</span><span class="special">,</span><span class="number">9</span><span class="special">,</span><span class="number">10</span><span class="special">,</span>
+<span class="number">11</span><span class="special">,</span><span class="number">12</span><span class="special">,</span><span class="number">13</span><span class="special">,</span><span class="number">14</span><span class="special">,</span><span class="number">15</span><span class="special">,</span>
+<span class="number">11</span><span class="special">,</span><span class="number">12</span><span class="special">,</span><span class="number">13</span><span class="special">,</span><span class="number">14</span><span class="special">,</span><span class="number">15</span><span class="special">,</span>
</pre>
<p>
</p>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003 -2010 Thorsten Ottosen, Neil Groves<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2010 Thorsten Ottosen,
+ Neil Groves<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
projects / platform / upstream / boost.git / blobdiff