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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> |
| <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> |
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