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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="core.typeinfo"></a><a class="link" href="typeinfo.html" title="typeinfo">typeinfo</a>
  28 </h2></div></div></div>
  29 <div class="toc"><dl class="toc"><dt><span class="section"><a href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp">Header
  30       &lt;boost/core/typeinfo.hpp&gt;</a></span></dt></dl></div>
  31 <div class="simplesect">
  32 <div class="titlepage"><div><div><h3 class="title">
  33 <a name="idm46687073118816"></a>Authors</h3></div></div></div>
  34 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
  35           Peter Dimov
  36         </li></ul></div>
  37 </div>
  38 <div class="section">
  39 <div class="titlepage"><div><div><h3 class="title">
  40 <a name="core.typeinfo.header_boost_core_typeinfo_hpp"></a><a class="link" href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp" title="Header &lt;boost/core/typeinfo.hpp&gt;">Header
  41       &lt;boost/core/typeinfo.hpp&gt;</a>
  42 </h3></div></div></div>
  43 <p>
  44         The header <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">core</span><span class="special">/</span><span class="identifier">typeinfo</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
  45         defines a class <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">typeinfo</span></code>, which is an alias for <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">type_info</span></code>
  46         when RTTI is enabled, and is a reasonable substitute when RTTI is not supported.
  47       </p>
  48 <p>
  49         The macro <code class="computeroutput"><span class="identifier">BOOST_CORE_TYPEID</span></code>,
  50         when applied to a type <code class="computeroutput"><span class="identifier">T</span></code>,
  51         is the equivalent of <code class="computeroutput"><span class="keyword">typeid</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code>
  52         and produces a reference to a const <code class="computeroutput"><span class="identifier">typeinfo</span></code>
  53         object.
  54       </p>
  55 <p>
  56         The function <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangled_name</span></code> takes a <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">typeinfo</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">ti</span></code> and either returns <code class="computeroutput"><span class="identifier">ti</span><span class="special">.</span><span class="identifier">name</span><span class="special">()</span></code>,
  57         when that string doesn't need to be demangled, or <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangle</span><span class="special">(</span><span class="identifier">ti</span><span class="special">.</span><span class="identifier">name</span><span class="special">())</span></code>,
  58         when it does. The return type of <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangled_name</span></code>
  59         is <code class="computeroutput"><span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span></code> in the first case and <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code>
  60         in the second.
  61       </p>
  62 <div class="section">
  63 <div class="titlepage"><div><div><h4 class="title">
  64 <a name="core.typeinfo.header_boost_core_typeinfo_hpp.synopsis"></a><a class="link" href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp.synopsis" title="Synopsis">Synopsis</a>
  65 </h4></div></div></div>
  66 <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span>
  67 <span class="special">{</span>
  68
  69 <span class="keyword">namespace</span> <span class="identifier">core</span>
  70 <span class="special">{</span>
  71     <span class="keyword">class</span> <span class="identifier">typeinfo</span><span class="special">;</span>
  72     <span class="comment">/* char const* or std::string */</span> <span class="identifier">demangled_name</span><span class="special">(</span> <span class="identifier">typeinfo</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">ti</span> <span class="special">);</span>
  73 <span class="special">}</span>
  74
  75 <span class="special">}</span>
  76
  77 <span class="preprocessor">#define</span> <span class="identifier">BOOST_CORE_TYPEID</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span> <span class="comment">/*unspecified*/</span>
  78 </pre>
  79 </div>
  80 <div class="section">
  81 <div class="titlepage"><div><div><h4 class="title">
  82 <a name="core.typeinfo.header_boost_core_typeinfo_hpp.example"></a><a class="link" href="typeinfo.html#core.typeinfo.header_boost_core_typeinfo_hpp.example" title="Example">Example</a>
  83 </h4></div></div></div>
  84 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">core</span><span class="special">/</span><span class="identifier">typeinfo</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
  85 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">iostream</span><span class="special">&gt;</span>
  86
  87 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T1</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">T2</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">X</span>
  88 <span class="special">{</span>
  89 <span class="special">};</span>
  90
  91 <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
  92 <span class="special">{</span>
  93     <span class="keyword">typedef</span> <span class="identifier">X</span><span class="special">&lt;</span><span class="keyword">void</span> <span class="keyword">const</span><span class="special">*,</span> <span class="keyword">void</span><span class="special">(*)(</span><span class="keyword">float</span><span class="special">)&gt;</span> <span class="identifier">T</span><span class="special">;</span>
  94
  95     <span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">typeinfo</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">ti</span> <span class="special">=</span> <span class="identifier">BOOST_CORE_TYPEID</span><span class="special">(</span><span class="identifier">T</span><span class="special">);</span>
  96
  97     <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">core</span><span class="special">::</span><span class="identifier">demangled_name</span><span class="special">(</span> <span class="identifier">ti</span> <span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>
  98 <span class="special">}</span>
  99 </pre>
 100 </div>
 101 </div>
 102 </div>
 103 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 104 <td align="left"></td>
 105 <td align="right"><div class="copyright-footer">Copyright &#169; 2014 Peter Dimov<br>Copyright &#169; 2014 Glen Fernandes<br>Copyright &#169; 2014 Andrey Semashev<p>
 106         Distributed under the <a href="http://boost.org/LICENSE_1_0.txt" target="_top">Boost
 107         Software License, Version 1.0</a>.
 108       </p>
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