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<html>
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<title>conversion_traits<> traits class</title>
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<div class="section" title="conversion_traits<> traits class">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_numericconversion.conversion_traits___traits_class"></a><a class="link" href="conversion_traits___traits_class.html" title="conversion_traits<> traits class">conversion_traits<>
traits class</a>
</h2></div></div></div>
<div class="toc"><dl>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types">Types</a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.examples">Examples</a></span></dt>
</dl></div>
<div class="section" title="Types">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types" title="Types">Types</a>
</h3></div></div></div>
<div class="toc"><dl>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum">enumeration
int_float_mixture_enum</a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum">enumeration
sign_mixture_enum</a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum">enumeration
udt_builtin_mixture_enum</a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__">template
class int_float_mixture<></a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__">template
class sign_mixture<></a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_udt_builtin_mixture__">template
class udt_builtin_mixture<></a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_is_subranged__">template
class is_subranged<></a></span></dt>
<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_conversion_traits__">template
class conversion_traits<></a></span></dt>
</dl></div>
<div class="section" title="enumeration int_float_mixture_enum">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum" title="enumeration int_float_mixture_enum">enumeration
int_float_mixture_enum</a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">enum</span> <span class="identifier">int_float_mixture_enum</span>
<span class="special">{</span>
<span class="identifier">integral_to_integral</span>
<span class="special">,</span><span class="identifier">integral_to_float</span>
<span class="special">,</span><span class="identifier">float_to_integral</span>
<span class="special">,</span><span class="identifier">float_to_float</span>
<span class="special">}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
</span></pre>
</div>
<div class="section" title="enumeration sign_mixture_enum">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum" title="enumeration sign_mixture_enum">enumeration
sign_mixture_enum</a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">enum</span> <span class="identifier">sign_mixture_enum</span>
<span class="special">{</span>
<span class="identifier">unsigned_to_unsigned</span>
<span class="special">,</span><span class="identifier">signed_to_signed</span>
<span class="special">,</span><span class="identifier">signed_to_unsigned</span>
<span class="special">,</span><span class="identifier">unsigned_to_signed</span>
<span class="special">}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
</span></pre>
</div>
<div class="section" title="enumeration udt_builtin_mixture_enum">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum" title="enumeration udt_builtin_mixture_enum">enumeration
udt_builtin_mixture_enum</a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">enum</span> <span class="identifier">udt_builtin_mixture_enum</span>
<span class="special">{</span>
<span class="identifier">builtin_to_builtin</span>
<span class="special">,</span><span class="identifier">builtin_to_udt</span>
<span class="special">,</span><span class="identifier">udt_to_builtin</span>
<span class="special">,</span><span class="identifier">udt_to_udt</span>
<span class="special">}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
</span></pre>
</div>
<div class="section" title="template class int_float_mixture<>">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__" title="template class int_float_mixture<>">template
class int_float_mixture<></a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">S</span><span class="special">></span>
<span class="keyword">struct</span> <span class="identifier">int_float_mixture</span> <span class="special">:</span> <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special"><</span><span class="identifier">int_float_mixture_enum</span><span class="special">,</span> <span class="identifier">impl</span><span class="special">-</span><span class="identifier">def</span><span class="special">-</span><span class="identifier">value</span><span class="special">></span> <span class="special">{}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
</span></pre>
<p>
Classifying <code class="computeroutput"><span class="identifier">S</span></code> and <code class="computeroutput"><span class="identifier">T</span></code> as either integral or float, this
<a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
Integral Constant</a> indicates the combination of these attributes.
</p>
<p>
Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
is of enumeration type <a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum" title="enumeration int_float_mixture_enum"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">int_float_mixture_enum</span></code></a>
</p>
</div>
<div class="section" title="template class sign_mixture<>">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__" title="template class sign_mixture<>">template
class sign_mixture<></a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">S</span><span class="special">></span>
<span class="keyword">struct</span> <span class="identifier">sign_mixture</span> <span class="special">:</span> <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special"><</span><span class="identifier">sign_mixture_enum</span><span class="special">,</span> <span class="identifier">impl</span><span class="special">-</span><span class="identifier">def</span><span class="special">-</span><span class="identifier">value</span><span class="special">></span> <span class="special">{}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
</span></pre>
<p>
Classifying <code class="computeroutput"><span class="identifier">S</span></code> and <code class="computeroutput"><span class="identifier">T</span></code> as either signed or unsigned, this
<a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
Integral Constant</a> indicates the combination of these attributes.
</p>
<p>
Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
is of enumeration type <a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum" title="enumeration sign_mixture_enum"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">sign_mixture_enum</span></code></a>
</p>
</div>
<div class="section" title="template class udt_builtin_mixture<>">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_udt_builtin_mixture__"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_udt_builtin_mixture__" title="template class udt_builtin_mixture<>">template
class udt_builtin_mixture<></a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">S</span><span class="special">></span>
<span class="keyword">struct</span> <span class="identifier">udt_builtin_mixture</span> <span class="special">:</span> <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special"><</span><span class="identifier">udt_builtin__mixture_enum</span><span class="special">,</span> <span class="identifier">impl</span><span class="special">-</span><span class="identifier">def</span><span class="special">-</span><span class="identifier">value</span><span class="special">></span> <span class="special">{}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
</span></pre>
<p>
Classifying <code class="computeroutput"><span class="identifier">S</span></code> and <code class="computeroutput"><span class="identifier">T</span></code> as either user-defined or builtin,
this <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
Integral Constant</a> indicates the combination of these attributes.
</p>
<p>
Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
is of enumeration type <a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum" title="enumeration udt_builtin_mixture_enum"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">udt_builtin_mixture_enum</span></code></a>
</p>
</div>
<div class="section" title="template class is_subranged<>">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_is_subranged__"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_is_subranged__" title="template class is_subranged<>">template
class is_subranged<></a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">S</span><span class="special">></span>
<span class="keyword">struct</span> <span class="identifier">is_subranged</span> <span class="special">:</span> <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">bool_</span><span class="special"><</span><span class="identifier">impl</span><span class="special">-</span><span class="identifier">def</span><span class="special">-</span><span class="identifier">value</span><span class="special">></span> <span class="special">{}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
</span></pre>
<p>
Indicates if the range of the target type <code class="computeroutput"><span class="identifier">T</span></code>
is a subset of the range of the source type <code class="computeroutput"><span class="identifier">S</span></code>.
That is: if there are some source values which fall out of the Target type's
range.
</p>
<p>
It is a boolean <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
Integral Constant</a> .
</p>
<p>
It does not indicate if a particular conversion is effectively out of range;
it indicates that some conversion might be out of range because not all
the source values are representable as Target type.
</p>
</div>
<div class="section" title="template class conversion_traits<>">
<div class="titlepage"><div><div><h4 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_conversion_traits__"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_conversion_traits__" title="template class conversion_traits<>">template
class conversion_traits<></a>
</h4></div></div></div>
<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span> <span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">numeric</span> <span class="special">{</span>
<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">S</span><span class="special">></span>
<span class="keyword">struct</span> <span class="identifier">conversion_traits</span>
<span class="special">{</span>
<span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special"><</span><span class="identifier">int_float_mixture_enum</span> <span class="special">,</span> <span class="special">...></span> <span class="identifier">int_float_mixture</span> <span class="special">;</span>
<span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special"><</span><span class="identifier">sign_mixture_enum</span> <span class="special">,</span> <span class="special">...></span> <span class="identifier">sign_mixture</span><span class="special">;</span>
<span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special"><</span><span class="identifier">udt_builtin_mixture_enum</span><span class="special">,</span> <span class="special">...></span> <span class="identifier">udt_builtin_mixture</span> <span class="special">;</span>
<span class="identifier">mpl</span><span class="special">::</span><span class="identifier">bool_</span><span class="special"><...></span> <span class="identifier">subranged</span> <span class="special">;</span>
<span class="identifier">mpl</span><span class="special">::</span><span class="identifier">bool_</span><span class="special"><...></span> <span class="identifier">trivial</span> <span class="special">;</span>
<span class="keyword">typedef</span> <span class="identifier">T</span> <span class="identifier">target_type</span> <span class="special">;</span>
<span class="keyword">typedef</span> <span class="identifier">S</span> <span class="identifier">source_type</span> <span class="special">;</span>
<span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">argument_type</span> <span class="special">;</span>
<span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">result_type</span> <span class="special">;</span>
<span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">supertype</span> <span class="special">;</span>
<span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">subtype</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">;</span>
<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace numeric, namespace boost
</span></pre>
<p>
This traits class indicates some properties of a <span class="emphasis"><em>numeric conversion</em></span>
direction: from a source type <code class="computeroutput"><span class="identifier">S</span></code>
to a target type <code class="computeroutput"><span class="identifier">T</span></code>. It
does not indicate the properties of a <span class="emphasis"><em>specific</em></span> conversion,
but of the conversion direction. See <a class="link" href="definitions.html#boost_numericconversion.definitions.subranged_conversion_direction__subtype_and_supertype" title="Subranged Conversion Direction, Subtype and Supertype">Definitions</a>
for details.
</p>
<p>
The traits class provides the following <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
Integral Constant</a> \s of enumeration type. They express the combination
of certain attributes of the Source and Target types (thus they are call
mixture):
</p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
</p>
</th>
<th>
<p>
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
<span class="bold"><strong>int_float_mixture </strong></span>
</p>
</td>
<td>
<p>
Same as given by the traits class <a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__" title="template class int_float_mixture<>">int_float_mixture</a>
</p>
</td>
</tr>
<tr>
<td>
<p>
<span class="bold"><strong>sign_mixture </strong></span>
</p>
</td>
<td>
<p>
Same as given by the traits class <a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__" title="template class sign_mixture<>">sign_mixture</a>
</p>
</td>
</tr>
<tr>
<td>
<p>
<span class="bold"><strong>udt_builtin_mixture </strong></span>
</p>
</td>
<td>
<p>
Same as given by the traits class <a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_udt_builtin_mixture__" title="template class udt_builtin_mixture<>">udt_builtin_mixture</a>
</p>
</td>
</tr>
</tbody>
</table></div>
<p>
The traits class provides the following <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
Integral Constant</a> \s of boolean type which indicates indirectly
the relation between the Source and Target ranges (see <a class="link" href="definitions.html#boost_numericconversion.definitions.range_and_precision" title="Range and Precision">Definitions</a>
for details).
</p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
</p>
</th>
<th>
<p>
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
subranged
</p>
</td>
<td>
<p>
Same as given by <a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_is_subranged__" title="template class is_subranged<>">is_subranged</a>
</p>
</td>
</tr>
<tr>
<td>
<p>
trivial
</p>
</td>
<td>
<p>
Indicates if both Source and Target, <span class="underline">without
cv-qualifications</span>, are the same type.
</p>
<p>
Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
is of boolean type.
</p>
</td>
</tr>
</tbody>
</table></div>
<p>
The traits class provides the following types. They are the Source and
Target types classified and qualified for different purposes.
</p>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
</p>
</th>
<th>
<p>
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
<span class="bold"><strong>target_type</strong></span>
</p>
</td>
<td>
<p>
The template parameter <code class="computeroutput"><span class="identifier">T</span></code>
without cv-qualifications
</p>
</td>
</tr>
<tr>
<td>
<p>
<span class="bold"><strong>source_type</strong></span>
</p>
</td>
<td>
<p>
The template parameter <code class="computeroutput"><span class="identifier">S</span></code>
without cv-qualifications
</p>
</td>
</tr>
<tr>
<td>
<p>
<span class="bold"><strong>argument_type</strong></span>
</p>
</td>
<td>
<p>
This type is either source_type or <code class="computeroutput"><span class="identifier">source_type</span>
<span class="keyword">const</span><span class="special">&</span></code>.
</p>
<p>
It represents the optimal argument type for the <a class="link" href="converter___function_object.html" title="converter<> function object">converter</a>
member functions.
</p>
<p>
If S is a built-in type, this is <code class="computeroutput"><span class="identifier">source_type</span></code>,
otherwise, this is <code class="computeroutput"><span class="identifier">source_type</span>
<span class="keyword">const</span><span class="special">&</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<span class="bold"><strong>result_type</strong></span>
</p>
</td>
<td>
<p>
This type is either target_type or target_type const&
</p>
<p>
It represents the return type of the <a class="link" href="converter___function_object.html" title="converter<> function object">converter</a>
member functions.
</p>
<p>
If <code class="computeroutput"><span class="identifier">T</span><span class="special">==</span><span class="identifier">S</span></code>, it is <code class="computeroutput"><span class="identifier">target_type</span>
<span class="keyword">const</span><span class="special">&</span></code>,
otherwise, it is <code class="computeroutput"><span class="identifier">target_type</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
<span class="bold"><strong>supertype</strong></span>
</p>
</td>
<td>
<p>
If the conversion is subranged, it is <code class="computeroutput"><span class="identifier">source_type</span></code>,
otherwise, it is <code class="computeroutput"><span class="identifier">target_type</span></code>
</p>
</td>
</tr>
<tr>
<td>
<p>
<span class="bold"><strong>subtype</strong></span>
</p>
</td>
<td>
<p>
If the conversion is subranged, it is <code class="computeroutput"><span class="identifier">target_type</span></code>,
otherwise, it is <code class="computeroutput"><span class="identifier">source_type</span></code>
</p>
</td>
</tr>
</tbody>
</table></div>
</div>
</div>
<div class="section" title="Examples">
<div class="titlepage"><div><div><h3 class="title">
<a name="boost_numericconversion.conversion_traits___traits_class.examples"></a><a class="link" href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.examples" title="Examples">Examples</a>
</h3></div></div></div>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">cassert</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">typeinfo</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">numeric</span><span class="special">/</span><span class="identifier">conversion</span><span class="special">/</span><span class="identifier">conversion_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
<span class="special">{</span>
<span class="comment">// A trivial conversion.
</span> <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">conversion_traits</span><span class="special"><</span><span class="keyword">short</span><span class="special">,</span><span class="keyword">short</span><span class="special">></span> <span class="identifier">Short2Short_Traits</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">Short2Short_Traits</span><span class="special">::</span><span class="identifier">trivial</span><span class="special">::</span><span class="identifier">value</span> <span class="special">)</span> <span class="special">;</span>
<span class="comment">// A subranged conversion.
</span> <span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">conversion_traits</span><span class="special"><</span><span class="keyword">double</span><span class="special">,</span><span class="keyword">unsigned</span> <span class="keyword">int</span><span class="special">></span> <span class="identifier">UInt2Double_Traits</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">UInt2Double_Traits</span><span class="special">::</span><span class="identifier">int_float_mixture</span><span class="special">::</span><span class="identifier">value</span> <span class="special">==</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">integral_to_float</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="identifier">UInt2Double_Traits</span><span class="special">::</span><span class="identifier">sign_mixture</span><span class="special">::</span><span class="identifier">value</span> <span class="special">==</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">unsigned_to_signed</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">!</span><span class="identifier">UInt2Double_Traits</span><span class="special">::</span><span class="identifier">subranged</span><span class="special">::</span><span class="identifier">value</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="keyword">typeid</span><span class="special">(</span><span class="identifier">UInt2Double_Traits</span><span class="special">::</span><span class="identifier">supertype</span><span class="special">)</span> <span class="special">==</span> <span class="keyword">typeid</span><span class="special">(</span><span class="keyword">double</span><span class="special">)</span> <span class="special">)</span> <span class="special">;</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="keyword">typeid</span><span class="special">(</span><span class="identifier">UInt2Double_Traits</span><span class="special">::</span><span class="identifier">subtype</span><span class="special">)</span> <span class="special">==</span> <span class="keyword">typeid</span><span class="special">(</span><span class="keyword">unsigned</span> <span class="keyword">int</span><span class="special">)</span> <span class="special">)</span> <span class="special">;</span>
<span class="comment">// A doubly subranged conversion.
</span> <span class="identifier">assert</span> <span class="special">(</span> <span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">conversion_traits</span><span class="special"><</span><span class="keyword">short</span><span class="special">,</span> <span class="keyword">unsigned</span> <span class="keyword">short</span><span class="special">>::</span><span class="identifier">subranged</span><span class="special">::</span><span class="identifier">value</span><span class="special">)</span> <span class="special">);</span>
<span class="identifier">assert</span> <span class="special">(</span> <span class="special">(</span><span class="identifier">boost</span><span class="special">::</span><span class="identifier">numeric</span><span class="special">::</span><span class="identifier">conversion_traits</span><span class="special"><</span><span class="keyword">unsigned</span> <span class="keyword">short</span><span class="special">,</span> <span class="keyword">short</span><span class="special">>::</span><span class="identifier">subranged</span><span class="special">::</span><span class="identifier">value</span><span class="special">)</span> <span class="special">);</span>
<span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
<span class="special">}</span>
</pre>
</div>
</div>
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<td align="right"><div class="copyright-footer">Copyright 2004 -2007 Fernando Luis Cacciola Carballal<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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