ceph/src/boost/libs/numeric/conversion/doc/html/boost_numericconversion/conversion_traits___traits_class.html

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  24 </div>
  25 <div class="section">
  26 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
  27 <a name="boost_numericconversion.conversion_traits___traits_class"></a><a class="link" href="conversion_traits___traits_class.html" title="conversion_traits&lt;&gt; traits class">conversion_traits&lt;&gt;
  28     traits class</a>
  29 </h2></div></div></div>
  30 <div class="toc"><dl class="toc">
  31 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types">Types</a></span></dt>
  32 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.examples">Examples</a></span></dt>
  33 </dl></div>
  34 <div class="section">
  35 <div class="titlepage"><div><div><h3 class="title">
  36 <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>
  37 </h3></div></div></div>
  38 <div class="toc"><dl class="toc">
  39 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_int_float_mixture_enum">enumeration
  40         int_float_mixture_enum</a></span></dt>
  41 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_sign_mixture_enum">enumeration
  42         sign_mixture_enum</a></span></dt>
  43 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.enumeration_udt_builtin_mixture_enum">enumeration
  44         udt_builtin_mixture_enum</a></span></dt>
  45 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_int_float_mixture__">template
  46         class int_float_mixture&lt;&gt;</a></span></dt>
  47 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_sign_mixture__">template
  48         class sign_mixture&lt;&gt;</a></span></dt>
  49 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_udt_builtin_mixture__">template
  50         class udt_builtin_mixture&lt;&gt;</a></span></dt>
  51 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_is_subranged__">template
  52         class is_subranged&lt;&gt;</a></span></dt>
  53 <dt><span class="section"><a href="conversion_traits___traits_class.html#boost_numericconversion.conversion_traits___traits_class.types.template_class_conversion_traits__">template
  54         class conversion_traits&lt;&gt;</a></span></dt>
  55 </dl></div>
  56 <div class="section">
  57 <div class="titlepage"><div><div><h4 class="title">
  58 <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
  59         int_float_mixture_enum</a>
  60 </h4></div></div></div>
  61 <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>
  62
  63     <span class="keyword">enum</span> <span class="identifier">int_float_mixture_enum</span>
  64     <span class="special">{</span>
  65        <span class="identifier">integral_to_integral</span>
  66       <span class="special">,</span><span class="identifier">integral_to_float</span>
  67       <span class="special">,</span><span class="identifier">float_to_integral</span>
  68       <span class="special">,</span><span class="identifier">float_to_float</span>
  69     <span class="special">}</span> <span class="special">;</span>
  70
  71 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric</span>
  72 </pre>
  73 </div>
  74 <div class="section">
  75 <div class="titlepage"><div><div><h4 class="title">
  76 <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
  77         sign_mixture_enum</a>
  78 </h4></div></div></div>
  79 <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>
  80
  81 <span class="keyword">enum</span> <span class="identifier">sign_mixture_enum</span>
  82 <span class="special">{</span>
  83    <span class="identifier">unsigned_to_unsigned</span>
  84   <span class="special">,</span><span class="identifier">signed_to_signed</span>
  85   <span class="special">,</span><span class="identifier">signed_to_unsigned</span>
  86   <span class="special">,</span><span class="identifier">unsigned_to_signed</span>
  87 <span class="special">}</span> <span class="special">;</span>
  88
  89 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric</span>
  90 </pre>
  91 </div>
  92 <div class="section">
  93 <div class="titlepage"><div><div><h4 class="title">
  94 <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
  95         udt_builtin_mixture_enum</a>
  96 </h4></div></div></div>
  97 <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>
  98
  99     <span class="keyword">enum</span> <span class="identifier">udt_builtin_mixture_enum</span>
 100     <span class="special">{</span>
 101        <span class="identifier">builtin_to_builtin</span>
 102       <span class="special">,</span><span class="identifier">builtin_to_udt</span>
 103       <span class="special">,</span><span class="identifier">udt_to_builtin</span>
 104       <span class="special">,</span><span class="identifier">udt_to_udt</span>
 105     <span class="special">}</span> <span class="special">;</span>
 106
 107 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric</span>
 108 </pre>
 109 </div>
 110 <div class="section">
 111 <div class="titlepage"><div><div><h4 class="title">
 112 <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&lt;&gt;">template
 113         class int_float_mixture&lt;&gt;</a>
 114 </h4></div></div></div>
 115 <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>
 116
 117     <span class="keyword">template</span> <span class="special">&lt;</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">&gt;</span>
 118     <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">&lt;</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">&gt;</span> <span class="special">{}</span> <span class="special">;</span>
 119
 120 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric</span>
 121 </pre>
 122 <p>
 123           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
 124           <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
 125           Integral Constant</a> indicates the combination of these attributes.
 126         </p>
 127 <p>
 128           Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
 129           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>
 130         </p>
 131 </div>
 132 <div class="section">
 133 <div class="titlepage"><div><div><h4 class="title">
 134 <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&lt;&gt;">template
 135         class sign_mixture&lt;&gt;</a>
 136 </h4></div></div></div>
 137 <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>
 138
 139     <span class="keyword">template</span> <span class="special">&lt;</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">&gt;</span>
 140     <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">&lt;</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">&gt;</span> <span class="special">{}</span> <span class="special">;</span>
 141
 142 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric</span>
 143 </pre>
 144 <p>
 145           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
 146           <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
 147           Integral Constant</a> indicates the combination of these attributes.
 148         </p>
 149 <p>
 150           Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
 151           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>
 152         </p>
 153 </div>
 154 <div class="section">
 155 <div class="titlepage"><div><div><h4 class="title">
 156 <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&lt;&gt;">template
 157         class udt_builtin_mixture&lt;&gt;</a>
 158 </h4></div></div></div>
 159 <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>
 160
 161     <span class="keyword">template</span> <span class="special">&lt;</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">&gt;</span>
 162     <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">&lt;</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">&gt;</span> <span class="special">{}</span> <span class="special">;</span>
 163
 164 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric</span>
 165 </pre>
 166 <p>
 167           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,
 168           this <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
 169           Integral Constant</a> indicates the combination of these attributes.
 170         </p>
 171 <p>
 172           Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
 173           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>
 174         </p>
 175 </div>
 176 <div class="section">
 177 <div class="titlepage"><div><div><h4 class="title">
 178 <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&lt;&gt;">template
 179         class is_subranged&lt;&gt;</a>
 180 </h4></div></div></div>
 181 <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>
 182
 183     <span class="keyword">template</span> <span class="special">&lt;</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">&gt;</span>
 184     <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">&lt;</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">&gt;</span> <span class="special">{}</span> <span class="special">;</span>
 185
 186 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace boost::numeric</span>
 187 </pre>
 188 <p>
 189           Indicates if the range of the target type <code class="computeroutput"><span class="identifier">T</span></code>
 190           is a subset of the range of the source type <code class="computeroutput"><span class="identifier">S</span></code>.
 191           That is: if there are some source values which fall out of the Target type's
 192           range.
 193         </p>
 194 <p>
 195           It is a boolean <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
 196           Integral Constant</a> .
 197         </p>
 198 <p>
 199           It does not indicate if a particular conversion is effectively out of range;
 200           it indicates that some conversion might be out of range because not all
 201           the source values are representable as Target type.
 202         </p>
 203 </div>
 204 <div class="section">
 205 <div class="titlepage"><div><div><h4 class="title">
 206 <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&lt;&gt;">template
 207         class conversion_traits&lt;&gt;</a>
 208 </h4></div></div></div>
 209 <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>
 210
 211     <span class="keyword">template</span> <span class="special">&lt;</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">&gt;</span>
 212     <span class="keyword">struct</span> <span class="identifier">conversion_traits</span>
 213     <span class="special">{</span>
 214         <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special">&lt;</span><span class="identifier">int_float_mixture_enum</span>  <span class="special">,</span> <span class="special">...&gt;</span> <span class="identifier">int_float_mixture</span> <span class="special">;</span>
 215         <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special">&lt;</span><span class="identifier">sign_mixture_enum</span>       <span class="special">,</span> <span class="special">...&gt;</span> <span class="identifier">sign_mixture</span><span class="special">;</span>
 216         <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">integral_c</span><span class="special">&lt;</span><span class="identifier">udt_builtin_mixture_enum</span><span class="special">,</span> <span class="special">...&gt;</span> <span class="identifier">udt_builtin_mixture</span> <span class="special">;</span>
 217
 218         <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">bool_</span><span class="special">&lt;...&gt;</span> <span class="identifier">subranged</span> <span class="special">;</span>
 219         <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">bool_</span><span class="special">&lt;...&gt;</span> <span class="identifier">trivial</span> <span class="special">;</span>
 220
 221         <span class="keyword">typedef</span> <span class="identifier">T</span> <span class="identifier">target_type</span>   <span class="special">;</span>
 222         <span class="keyword">typedef</span> <span class="identifier">S</span> <span class="identifier">source_type</span>   <span class="special">;</span>
 223         <span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">argument_type</span> <span class="special">;</span>
 224         <span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">result_type</span>   <span class="special">;</span>
 225         <span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">supertype</span>     <span class="special">;</span>
 226         <span class="keyword">typedef</span> <span class="special">...</span> <span class="identifier">subtype</span>       <span class="special">;</span>
 227     <span class="special">}</span> <span class="special">;</span>
 228
 229 <span class="special">}</span> <span class="special">}</span> <span class="comment">// namespace numeric, namespace boost</span>
 230 </pre>
 231 <p>
 232           This traits class indicates some properties of a <span class="emphasis"><em>numeric conversion</em></span>
 233           direction: from a source type <code class="computeroutput"><span class="identifier">S</span></code>
 234           to a target type <code class="computeroutput"><span class="identifier">T</span></code>. It
 235           does not indicate the properties of a <span class="emphasis"><em>specific</em></span> conversion,
 236           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>
 237           for details.
 238         </p>
 239 <p>
 240           The traits class provides the following <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
 241           Integral Constant</a> \s of enumeration type. They express the combination
 242           of certain attributes of the Source and Target types (thus they are call
 243           mixture):
 244         </p>
 245 <div class="informaltable"><table class="table">
 246 <colgroup>
 247 <col>
 248 <col>
 249 </colgroup>
 250 <thead><tr>
 251 <th>
 252                 </th>
 253 <th>
 254                 </th>
 255 </tr></thead>
 256 <tbody>
 257 <tr>
 258 <td>
 259                   <p>
 260                     <span class="bold"><strong>int_float_mixture </strong></span>
 261                   </p>
 262                 </td>
 263 <td>
 264                   <p>
 265                     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&lt;&gt;">int_float_mixture</a>
 266                   </p>
 267                 </td>
 268 </tr>
 269 <tr>
 270 <td>
 271                   <p>
 272                     <span class="bold"><strong>sign_mixture </strong></span>
 273                   </p>
 274                 </td>
 275 <td>
 276                   <p>
 277                     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&lt;&gt;">sign_mixture</a>
 278                   </p>
 279                 </td>
 280 </tr>
 281 <tr>
 282 <td>
 283                   <p>
 284                     <span class="bold"><strong>udt_builtin_mixture </strong></span>
 285                   </p>
 286                 </td>
 287 <td>
 288                   <p>
 289                     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&lt;&gt;">udt_builtin_mixture</a>
 290                   </p>
 291                 </td>
 292 </tr>
 293 </tbody>
 294 </table></div>
 295 <p>
 296           The traits class provides the following <a href="../../../../../mpl/doc/refmanual/integral-constant.html" target="_top">MPL's
 297           Integral Constant</a> \s of boolean type which indicates indirectly
 298           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>
 299           for details).
 300         </p>
 301 <div class="informaltable"><table class="table">
 302 <colgroup>
 303 <col>
 304 <col>
 305 </colgroup>
 306 <thead><tr>
 307 <th>
 308                 </th>
 309 <th>
 310                 </th>
 311 </tr></thead>
 312 <tbody>
 313 <tr>
 314 <td>
 315                   <p>
 316                     subranged
 317                   </p>
 318                 </td>
 319 <td>
 320                   <p>
 321                     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&lt;&gt;">is_subranged</a>
 322                   </p>
 323                 </td>
 324 </tr>
 325 <tr>
 326 <td>
 327                   <p>
 328                     trivial
 329                   </p>
 330                 </td>
 331 <td>
 332                   <p>
 333                     Indicates if both Source and Target, <span class="underline">without
 334                     cv-qualifications</span>, are the same type.
 335                   </p>
 336                   <p>
 337                     Its <code class="computeroutput"><span class="special">::</span><span class="identifier">value</span></code>
 338                     is of boolean type.
 339                   </p>
 340                 </td>
 341 </tr>
 342 </tbody>
 343 </table></div>
 344 <p>
 345           The traits class provides the following types. They are the Source and
 346           Target types classified and qualified for different purposes.
 347         </p>
 348 <div class="informaltable"><table class="table">
 349 <colgroup>
 350 <col>
 351 <col>
 352 </colgroup>
 353 <thead><tr>
 354 <th>
 355                 </th>
 356 <th>
 357                 </th>
 358 </tr></thead>
 359 <tbody>
 360 <tr>
 361 <td>
 362                   <p>
 363                     <span class="bold"><strong>target_type</strong></span>
 364                   </p>
 365                 </td>
 366 <td>
 367                   <p>
 368                     The template parameter <code class="computeroutput"><span class="identifier">T</span></code>
 369                     without cv-qualifications
 370                   </p>
 371                 </td>
 372 </tr>
 373 <tr>
 374 <td>
 375                   <p>
 376                     <span class="bold"><strong>source_type</strong></span>
 377                   </p>
 378                 </td>
 379 <td>
 380                   <p>
 381                     The template parameter <code class="computeroutput"><span class="identifier">S</span></code>
 382                     without cv-qualifications
 383                   </p>
 384                 </td>
 385 </tr>
 386 <tr>
 387 <td>
 388                   <p>
 389                     <span class="bold"><strong>argument_type</strong></span>
 390                   </p>
 391                 </td>
 392 <td>
 393                   <p>
 394                     This type is either source_type or <code class="computeroutput"><span class="identifier">source_type</span>
 395                     <span class="keyword">const</span><span class="special">&amp;</span></code>.
 396                   </p>
 397                   <p>
 398                     It represents the optimal argument type for the <a class="link" href="converter___function_object.html" title="converter&lt;&gt; function object">converter</a>
 399                     member functions.
 400                   </p>
 401                   <p>
 402                     If S is a built-in type, this is <code class="computeroutput"><span class="identifier">source_type</span></code>,
 403                     otherwise, this is <code class="computeroutput"><span class="identifier">source_type</span>
 404                     <span class="keyword">const</span><span class="special">&amp;</span></code>.
 405                   </p>
 406                 </td>
 407 </tr>
 408 <tr>
 409 <td>
 410                   <p>
 411                     <span class="bold"><strong>result_type</strong></span>
 412                   </p>
 413                 </td>
 414 <td>
 415                   <p>
 416                     This type is either target_type or target_type const&amp;
 417                   </p>
 418                   <p>
 419                     It represents the return type of the <a class="link" href="converter___function_object.html" title="converter&lt;&gt; function object">converter</a>
 420                     member functions.
 421                   </p>
 422                   <p>
 423                     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>
 424                     <span class="keyword">const</span><span class="special">&amp;</span></code>,
 425                     otherwise, it is <code class="computeroutput"><span class="identifier">target_type</span></code>.
 426                   </p>
 427                 </td>
 428 </tr>
 429 <tr>
 430 <td>
 431                   <p>
 432                     <span class="bold"><strong>supertype</strong></span>
 433                   </p>
 434                 </td>
 435 <td>
 436                   <p>
 437                     If the conversion is subranged, it is <code class="computeroutput"><span class="identifier">source_type</span></code>,
 438                     otherwise, it is <code class="computeroutput"><span class="identifier">target_type</span></code>
 439                   </p>
 440                 </td>
 441 </tr>
 442 <tr>
 443 <td>
 444                   <p>
 445                     <span class="bold"><strong>subtype</strong></span>
 446                   </p>
 447                 </td>
 448 <td>
 449                   <p>
 450                     If the conversion is subranged, it is <code class="computeroutput"><span class="identifier">target_type</span></code>,
 451                     otherwise, it is <code class="computeroutput"><span class="identifier">source_type</span></code>
 452                   </p>
 453                 </td>
 454 </tr>
 455 </tbody>
 456 </table></div>
 457 </div>
 458 </div>
 459 <div class="section">
 460 <div class="titlepage"><div><div><h3 class="title">
 461 <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>
 462 </h3></div></div></div>
 463 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">cassert</span><span class="special">&gt;</span>
 464 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">typeinfo</span><span class="special">&gt;</span>
 465 <span class="preprocessor">#include</span> <span class="special">&lt;</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">&gt;</span>
 466
 467 <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
 468 <span class="special">{</span>
 469
 470     <span class="comment">// A trivial conversion.</span>
 471     <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">&lt;</span><span class="keyword">short</span><span class="special">,</span><span class="keyword">short</span><span class="special">&gt;</span> <span class="identifier">Short2Short_Traits</span> <span class="special">;</span>
 472     <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>
 473
 474     <span class="comment">// A subranged conversion.</span>
 475     <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">&lt;</span><span class="keyword">double</span><span class="special">,</span><span class="keyword">unsigned</span> <span class="keyword">int</span><span class="special">&gt;</span> <span class="identifier">UInt2Double_Traits</span> <span class="special">;</span>
 476     <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>
 477     <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>
 478     <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>
 479     <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>
 480     <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>
 481
 482     <span class="comment">// A doubly subranged conversion.</span>
 483     <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">&lt;</span><span class="keyword">short</span><span class="special">,</span> <span class="keyword">unsigned</span> <span class="keyword">short</span><span class="special">&gt;::</span><span class="identifier">subranged</span><span class="special">::</span><span class="identifier">value</span><span class="special">)</span> <span class="special">);</span>
 484     <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">&lt;</span><span class="keyword">unsigned</span> <span class="keyword">short</span><span class="special">,</span> <span class="keyword">short</span><span class="special">&gt;::</span><span class="identifier">subranged</span><span class="special">::</span><span class="identifier">value</span><span class="special">)</span> <span class="special">);</span>
 485
 486     <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
 487 <span class="special">}</span>
 488 </pre>
 489 </div>
 490 </div>
 491 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 492 <td align="left"></td>
 493 <td align="right"><div class="copyright-footer">Copyright &#169; 2004-2007 Fernando
 494       Luis Cacciola Carballal<p>
 495         Distributed under the Boost Software License, Version 1.0. (See accompanying
 496         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>)
 497       </p>
 498 </div></td>
 499 </tr></table>
 500 <hr>
 501 <div class="spirit-nav">
 502 <a accesskey="p" href="bounds___traits_class.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../index.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="numeric_converter_policy_classes.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
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