123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505 |
- <html>
- <head>
- <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
- <title>conversion_traits<> traits class</title>
- <link rel="stylesheet" href="../boostbook.css" type="text/css">
- <meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
- <link rel="home" href="../index.html" title="Chapter 1. Boost.NumericConversion">
- <link rel="up" href="../index.html" title="Chapter 1. Boost.NumericConversion">
- <link rel="prev" href="bounds___traits_class.html" title="bounds<> traits class">
- <link rel="next" href="numeric_converter_policy_classes.html" title="Numeric Converter Policy Classes">
- </head>
- <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
- <table cellpadding="2" width="100%"><tr>
- <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td>
- <td align="center"><a href="../../../../../../index.html">Home</a></td>
- <td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td>
- <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
- <td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
- <td align="center"><a href="../../../../../../more/index.htm">More</a></td>
- </tr></table>
- <hr>
- <div class="spirit-nav">
- <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>
- </div>
- <div class="section">
- <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 class="toc">
- <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">
- <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 class="toc">
- <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">
- <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">
- <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">
- <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">
- <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">
- <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">
- <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">
- <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">
- <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>
- </th>
- <th>
- </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>
- </th>
- <th>
- </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>
- </th>
- <th>
- </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">
- <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>
- <div class="spirit-nav">
- <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>
- </div>
- </body>
- </html>
|