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<div class="titlepage">
<div><div><h3 class="title">
<a name="fusion.view.transform_view"></a><a href="transform_view.html" title="transform_view">transform_view</a>
</h3></div></div>
<div></div>
</div>
<p>
The unary version of <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
presents a view of its underlying sequence given a unary function object
or function pointer. The binary version of <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
presents a view of 2 underlying sequences, given a binary function object
or function pointer. The <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
inherits the traversal characteristics (see <a href="../sequence/concepts.html#fusion.sequence.concepts.traversal">Sequence
Traversal Concept</a>) of its underlying sequence or sequences.
</p>
<a name="fusion.view.transform_view.header"></a><h4>
<a name="id524861"></a>
<a href="transform_view.html#fusion.view.transform_view.header">Header</a>
</h4>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">view</span><span class="special">/</span><span class="identifier">transform_view</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">transform_view</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<a name="fusion.view.transform_view.synopsis"></a><h4>
<a name="id525017"></a>
<a href="transform_view.html#fusion.view.transform_view.synopsis">Synopsis</a>
</h4>
<p>
<span class="bold"><b>Unary Version</b></span>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Sequence</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F1</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">transform_view</span><span class="special">;</span>
</pre>
<p>
<span class="bold"><b>Binary Version</b></span>
</p>
<pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Sequence1</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">Sequence2</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">F2</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">transform_view</span><span class="special">;</span>
</pre>
<a name="fusion.view.transform_view.template_parameters"></a><h4>
<a name="id525221"></a>
<a href="transform_view.html#fusion.view.transform_view.template_parameters">Template parameters</a>
</h4>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th><p>
Parameter
</p></th>
<th><p>
Description
</p></th>
<th><p>
Default
</p></th>
</tr></thead>
<tbody>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">Sequence</span></tt>
</p></td>
<td><p>
A <a href="../sequence/concepts/forward_sequence.html" title="Forward
Sequence">Forward
Sequence</a>
</p></td>
<td><p>
</p></td>
</tr>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">Sequence1</span></tt>
</p></td>
<td><p>
A <a href="../sequence/concepts/forward_sequence.html" title="Forward
Sequence">Forward
Sequence</a>
</p></td>
<td><p>
</p></td>
</tr>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">Sequence2</span></tt>
</p></td>
<td><p>
A <a href="../sequence/concepts/forward_sequence.html" title="Forward
Sequence">Forward
Sequence</a>
</p></td>
<td><p>
</p></td>
</tr>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">F1</span></tt>
</p></td>
<td><p>
A unary function object or function pointer. <tt class="computeroutput"><a href="http://www.boost.org/libs/utility/utility.htm#result_of" target="_top"><tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">result_of</span></tt></a><span class="special">&lt;</span><span class="identifier">F1</span><span class="special">(</span><span class="identifier">E</span><span class="special">)&gt;::</span><span class="identifier">type</span></tt> is the return type of an instance
of <tt class="computeroutput"><span class="identifier">F1</span></tt> when called
with a value of each element type <tt class="computeroutput"><span class="identifier">E</span></tt>
in the input sequence.
</p></td>
<td><p>
</p></td>
</tr>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">F2</span></tt>
</p></td>
<td><p>
A binary function object or function pointer. <tt class="computeroutput"><a href="http://www.boost.org/libs/utility/utility.htm#result_of" target="_top"><tt class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">result_of</span></tt></a><span class="special">&lt;</span><span class="identifier">F2</span><span class="special">(</span><span class="identifier">E1</span><span class="special">,</span> <span class="identifier">E2</span><span class="special">)&gt;::</span><span class="identifier">type</span></tt> is the return type of an instance
of <tt class="computeroutput"><span class="identifier">F2</span></tt> when called
with a value of each corresponding pair of element type <tt class="computeroutput"><span class="identifier">E1</span></tt> and <tt class="computeroutput"><span class="identifier">E2</span></tt>
in the input sequences.
</p></td>
<td><p>
</p></td>
</tr>
</tbody>
</table></div>
<a name="fusion.view.transform_view.model_of"></a><h4>
<a name="id525686"></a>
<a href="transform_view.html#fusion.view.transform_view.model_of">Model of</a>
</h4>
<div class="itemizedlist"><ul type="disc"><li>
<a href="../sequence/concepts/forward_sequence.html" title="Forward
Sequence">Forward Sequence</a>,
<a href="../sequence/concepts/bidirectional_sequence.html" title="Bidirectional
Sequence">Bidirectional
Sequence</a> or <a href="../sequence/concepts/random_access_sequence.html" title="Random
Access Sequence">Random
Access Sequence</a> depending on the traversal characteristics (see
<a href="../sequence/concepts.html#fusion.sequence.concepts.traversal">Sequence Traversal Concept</a>)
of its underlying sequence.
</li></ul></div>
<div class="variablelist">
<p class="title"><b>Notation</b></p>
<dl>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">TV</span></tt></span></dt>
<dd><p>
A <tt class="computeroutput"><span class="identifier">transform_view</span></tt> type
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">BTV</span></tt></span></dt>
<dd><p>
A binary <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
type
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">UTV</span></tt></span></dt>
<dd><p>
A unary <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
type
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">f1</span></tt></span></dt>
<dd><p>
An instance of <tt class="computeroutput"><span class="identifier">F1</span></tt>
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">f2</span></tt></span></dt>
<dd><p>
An instance of <tt class="computeroutput"><span class="identifier">F2</span></tt>
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">s</span></tt></span></dt>
<dd><p>
An instance of <tt class="computeroutput"><span class="identifier">Sequence</span></tt>
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">s1</span></tt></span></dt>
<dd><p>
An instance of <tt class="computeroutput"><span class="identifier">Sequence1</span></tt>
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">s2</span></tt></span></dt>
<dd><p>
An instance of <tt class="computeroutput"><span class="identifier">Sequence2</span></tt>
</p></dd>
<dt><span class="term"><tt class="computeroutput"><span class="identifier">tv</span></tt>,
<tt class="computeroutput"><span class="identifier">tv2</span></tt></span></dt>
<dd><p>
Instances of <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
</p></dd>
</dl>
</div>
<a name="fusion.view.transform_view.expression_semantics"></a><h4>
<a name="id526088"></a>
<a href="transform_view.html#fusion.view.transform_view.expression_semantics">Expression
Semantics</a>
</h4>
<p>
Semantics of an expression is defined only where it differs from, or is not
defined in <a href="../sequence/concepts/forward_sequence.html" title="Forward
Sequence">Forward
Sequence</a>, <a href="../sequence/concepts/bidirectional_sequence.html" title="Bidirectional
Sequence">Bidirectional
Sequence</a> or <a href="../sequence/concepts/random_access_sequence.html" title="Random
Access Sequence">Random
Access Sequence</a> depending on the traversal characteristics (see <a href="../sequence/concepts.html#fusion.sequence.concepts.traversal">Sequence Traversal Concept</a>)
of its underlying sequence or sequences.
</p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th><p>
Expression
</p></th>
<th><p>
Semantics
</p></th>
</tr></thead>
<tbody>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">UTV</span><span class="special">(</span><span class="identifier">s</span><span class="special">,</span> <span class="identifier">f1</span><span class="special">)</span></tt>
</p></td>
<td><p>
Creates a unary <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
given sequence, <tt class="computeroutput"><span class="identifier">s</span></tt>
and unary function object or function pointer, <tt class="computeroutput"><span class="identifier">f1</span></tt>.
</p></td>
</tr>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">BTV</span><span class="special">(</span><span class="identifier">s1</span><span class="special">,</span> <span class="identifier">s2</span><span class="special">,</span> <span class="identifier">f2</span><span class="special">)</span></tt>
</p></td>
<td><p>
Creates a binary <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
given sequences, <tt class="computeroutput"><span class="identifier">s1</span></tt>
and <tt class="computeroutput"><span class="identifier">s2</span></tt> and binary
function object or function pointer, <tt class="computeroutput"><span class="identifier">f2</span></tt>.
</p></td>
</tr>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">TV</span><span class="special">(</span><span class="identifier">tv</span><span class="special">)</span></tt>
</p></td>
<td><p>
Copy constructs a <tt class="computeroutput"><span class="identifier">transform_view</span></tt>
from another <tt class="computeroutput"><span class="identifier">transform_view</span></tt>,
<tt class="computeroutput"><span class="identifier">tv</span></tt>.
</p></td>
</tr>
<tr>
<td><p>
<tt class="computeroutput"><span class="identifier">tv</span> <span class="special">=</span>
<span class="identifier">tv2</span></tt>
</p></td>
<td><p>
Assigns to a <tt class="computeroutput"><span class="identifier">transform_view</span></tt>,
<tt class="computeroutput"><span class="identifier">tv</span></tt>, from another
<tt class="computeroutput"><span class="identifier">transform_view</span></tt>,
<tt class="computeroutput"><span class="identifier">tv2</span></tt>.
</p></td>
</tr>
</tbody>
</table></div>
<a name="fusion.view.transform_view.example"></a><h4>
<a name="id526566"></a>
<a href="transform_view.html#fusion.view.transform_view.example">Example</a>
</h4>
<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">square</span>
<span class="special">{</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Sig</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">result</span><span class="special">;</span>
<span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">U</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">result</span><span class="special">&lt;</span><span class="identifier">square</span><span class="special">(</span><span class="identifier">U</span><span class="special">)&gt;</span>
<span class="special">:</span> <span class="identifier">remove_reference</span><span class="special">&lt;</span><span class="identifier">U</span><span class="special">&gt;</span>
<span class="special">{};</span>
<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="identifier">T</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">T</span> <span class="identifier">x</span><span class="special">)</span> <span class="keyword">const</span>
<span class="special">{</span>
<span class="keyword">return</span> <span class="identifier">x</span> <span class="special">*</span> <span class="identifier">x</span><span class="special">;</span>
<span class="special">}</span>
<span class="special">};</span>
<span class="keyword">typedef</span> <a href="../container/vector.html" title="vector"><tt class="computeroutput"><span class="identifier">vector</span></tt></a><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span> <span class="keyword">short</span><span class="special">,</span> <span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">vector_type</span><span class="special">;</span>
<span class="identifier">vector_type</span> <span class="identifier">vec</span><span class="special">(</span><span class="number">2</span><span class="special">,</span> <span class="number">5</span><span class="special">,</span> <span class="number">3.3</span><span class="special">);</span>
<span class="identifier">transform_view</span><span class="special">&lt;</span><span class="identifier">vector_type</span><span class="special">,</span> <span class="identifier">square</span><span class="special">&gt;</span> <span class="identifier">transform</span><span class="special">(</span><span class="identifier">vec</span><span class="special">,</span> <span class="identifier">square</span><span class="special">());</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">transform</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
</pre>
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<td align="right"><div class="copyright-footer">Copyright © 2001-2007 Joel de Guzman, Dan Marsden, Tobias
Schwinger<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>
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