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<a name="boost_numericconversion.conversion_traits___traits_class"></a><a href="conversion_traits___traits_class.html" title="conversion_traits<>
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traits class">conversion_traits<>
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traits class</a>
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</h2></div></div></div>
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<div class="toc"><dl>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types">Types</a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.examples">Examples</a></span></dt>
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</dl></div>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_numericconversion.conversion_traits___traits_class.types"></a><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types" title="Types">Types</a>
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</h3></div></div></div>
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<div class="toc"><dl>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum">enumeration
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int_float_mixture_enum</a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum">enumeration
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sign_mixture_enum</a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum">enumeration
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udt_builtin_mixture_enum</a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__">template
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class int_float_mixture<></a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__">template
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class sign_mixture<></a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_udt_builtin_mixture__">template
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class udt_builtin_mixture<></a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_is_subranged__">template
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class is_subranged<></a></span></dt>
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<dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_conversion_traits__">template
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class conversion_traits<></a></span></dt>
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</dl></div>
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<a name="numeric_conversion_traits_int_float_mixture_enum"></a><p>
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</p>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h4 class="title">
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<a name="boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum"></a><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum" title="enumeration
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int_float_mixture_enum">enumeration
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int_float_mixture_enum</a>
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</h4></div></div></div>
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<pre class="programlisting">
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<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>
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<span class="keyword">enum</span> <span class="identifier">int_float_mixture_enum</span>
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<span class="special">{</span>
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<span class="identifier">integral_to_integral</span>
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<span class="special">,</span><span class="identifier">integral_to_float</span>
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<span class="special">,</span><span class="identifier">float_to_integral</span>
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<span class="special">,</span><span class="identifier">float_to_float</span>
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<span class="special">}</span> <span class="special">;</span>
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<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
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</span></pre>
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</div>
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<a name="numeric_conversion_traits_sign_mixture_enum"></a><p>
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</p>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h4 class="title">
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<a name="boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum"></a><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum" title="enumeration
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sign_mixture_enum">enumeration
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sign_mixture_enum</a>
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</h4></div></div></div>
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<pre class="programlisting">
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<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>
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<span class="keyword">enum</span> <span class="identifier">sign_mixture_enum</span>
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<span class="special">{</span>
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<span class="identifier">unsigned_to_unsigned</span>
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<span class="special">,</span><span class="identifier">signed_to_signed</span>
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<span class="special">,</span><span class="identifier">signed_to_unsigned</span>
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<span class="special">,</span><span class="identifier">unsigned_to_signed</span>
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<span class="special">}</span> <span class="special">;</span>
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<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
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</span></pre>
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</div>
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<a name="numeric_conversion_traits_udt_builtin_mixture_enum"></a><p>
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</p>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h4 class="title">
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<a name="boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum"></a><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum" title="enumeration
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udt_builtin_mixture_enum">enumeration
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udt_builtin_mixture_enum</a>
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</h4></div></div></div>
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<pre class="programlisting">
|
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<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>
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<span class="keyword">enum</span> <span class="identifier">udt_builtin_mixture_enum</span>
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<span class="special">{</span>
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<span class="identifier">builtin_to_builtin</span>
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<span class="special">,</span><span class="identifier">builtin_to_udt</span>
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<span class="special">,</span><span class="identifier">udt_to_builtin</span>
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<span class="special">,</span><span class="identifier">udt_to_udt</span>
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<span class="special">}</span> <span class="special">;</span>
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<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
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</span></pre>
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</div>
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<a name="numeric_conversion_traits_class_int_float_mixture"></a><p>
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</p>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h4 class="title">
|
||
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__"></a><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__" title="template
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class int_float_mixture<>">template
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class int_float_mixture<></a>
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||
</h4></div></div></div>
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<pre class="programlisting">
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<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>
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<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>
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<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>
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<span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric
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</span></pre>
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<p>
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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
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<a href="../../../../../mpl/refmanual/integral-constant.html" target="_top">MPL's Integral
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Constant</a> indicates the combination of these attributes.
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</p>
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<p>
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Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
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is of enumeration type <a href="conversion_traits___traits_class.html#numeric_conversion_traits_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>
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||
</p>
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||
</div>
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||
<a name="numeric_conversion_traits_class_sign_mixture"></a><p>
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||
</p>
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||
<div class="section" lang="en">
|
||
<div class="titlepage"><div><div><h4 class="title">
|
||
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__"></a><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__" title="template
|
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class sign_mixture<>">template
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||
class sign_mixture<></a>
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||
</h4></div></div></div>
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<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>
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||
|
||
<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/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 href="conversion_traits___traits_class.html#numeric_conversion_traits_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>
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||
<a name="numeric_conversion_traits_class_udt_builtin_mixture"></a><p>
|
||
</p>
|
||
<div class="section" lang="en">
|
||
<div class="titlepage"><div><div><h4 class="title">
|
||
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_udt_builtin_mixture__"></a><a 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/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 href="conversion_traits___traits_class.html#numeric_conversion_traits_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>
|
||
<a name="numeric_conversion_traits_is_subranged"></a><p>
|
||
</p>
|
||
<div class="section" lang="en">
|
||
<div class="titlepage"><div><div><h4 class="title">
|
||
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_is_subranged__"></a><a 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/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" lang="en">
|
||
<div class="titlepage"><div><div><h4 class="title">
|
||
<a name="boost_numericconversion.conversion_traits___traits_class.types.template_class_conversion_traits__"></a><a 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 href="definitions.html#numeric_conversion_definitions_subranged">Definitions</a>
|
||
for details.
|
||
</p>
|
||
<p>
|
||
The traits class provides the following <a href="../../../../../mpl/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 href="conversion_traits___traits_class.html#numeric_conversion_traits_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 href="conversion_traits___traits_class.html#numeric_conversion_traits_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 href="conversion_traits___traits_class.html#numeric_conversion_traits_class_udt_builtin_mixture">udt_builtin_mixture</a>
|
||
</p>
|
||
</td>
|
||
</tr>
|
||
</tbody>
|
||
</table></div>
|
||
<p>
|
||
The traits class provides the following <a href="../../../../../mpl/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 href="definitions.html#numeric_conversion_definitions_range">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 href="conversion_traits___traits_class.html#numeric_conversion_traits_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 href="../index.html#numeric_conversion_converter">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 href="../index.html#numeric_conversion_converter">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" lang="en">
|
||
<div class="titlepage"><div><div><h3 class="title">
|
||
<a name="boost_numericconversion.conversion_traits___traits_class.examples"></a><a 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>
|
||
<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 © 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>
|
||
</div></td>
|
||
</tr></table>
|
||
<hr>
|
||
<div class="spirit-nav">
|
||
<a accesskey="p" href="bounds___traits_class.html"><img src="../../../../../../doc/html/images/prev.png" alt="Prev"></a><a accesskey="u" href="../index.html"><img src="../../../../../../doc/html/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../../doc/html/images/home.png" alt="Home"></a><a accesskey="n" href="numeric_converter_policy_classes.html"><img src="../../../../../../doc/html/images/next.png" alt="Next"></a>
|
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|
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|
||
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