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<div><h2 class="title">
<a name="boost_typeindex"></a>Chapter&#160;1.&#160;Boost.TypeIndex 1.0</h2></div>
<div><p class="copyright">Copyright &#169; 2012 Antony Polukhin</p></div>
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<a name="boost_typeindex.legal"></a><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>)
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<p><b>Table of Contents</b></p>
<dl>
<dt><span class="section"><a href="index.html#boost_typeindex.motivation">Motivation</a></span></dt>
<dt><span class="section"><a href="boost_typeindex/getting_started.html">Getting started</a></span></dt>
<dt><span class="section"><a href="boost_typeindex/examples.html">Examples</a></span></dt>
<dt><span class="section"><a href="boost_typeindex_header_reference.html">Boost.TypeIndex Header Reference</a></span></dt>
<dd><dl><dt><span class="section"><a href="boost_typeindex_header_reference.html#header.boost.type_index_hpp">Header &lt;boost/type_index.hpp&gt;</a></span></dt></dl></dd>
<dt><span class="section"><a href="boost_typeindex/performance.html">Performance</a></span></dt>
<dt><span class="section"><a href="boost_typeindex/compiler_support.html">Compiler support</a></span></dt>
</dl>
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<div class="section boost_typeindex_motivation">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="boost_typeindex.motivation"></a><a class="link" href="index.html#boost_typeindex.motivation" title="Motivation">Motivation</a>
</h2></div></div></div>
<p>
      Sometimes getting and storing information about a template type at runtime
      is required. For such cases a construction like <code class="computeroutput"><span class="special">&amp;</span><span class="keyword">typeid</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code> or C++11 class <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">type_index</span></code>
      is usually used. And that is the point, where problems start:
    </p>
<div class="itemizedlist"><ul class="itemizedlist" type="disc">
<li class="listitem">
          <code class="computeroutput"><span class="keyword">typeid</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code> and
          <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">type_index</span></code> require Run Time Type Info
          (RTTI)
        </li>
<li class="listitem">
          some implementations of <code class="computeroutput"><span class="keyword">typeid</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code>
          strip const, volatile and references from type, while others don't
        </li>
<li class="listitem">
          some compilers have bugs and do not correctly compare <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">type_info</span></code>
          objects across shared libraries
        </li>
<li class="listitem">
          only a few implementations already provide <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">type_index</span></code>
        </li>
<li class="listitem">
          no easy way to store type info without stripping const, volatile and references
        </li>
<li class="listitem">
          no nice and portable way to get human readable type names
        </li>
</ul></div>
<p>
      Boost.TypeIndex was designed to work around those issues.
    </p>
<p>
      &#65279;
    </p>
<div class="note"><table border="0" summary="Note">
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<th align="left">Note</th>
</tr>
<tr><td align="left" valign="top"><p>
        <code class="computeroutput"><span class="identifier">T</span></code> means type here. Think
        of it as of <code class="computeroutput"><span class="identifier">T</span></code> in <code class="computeroutput"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span></code>
      </p></td></tr>
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<div class="warning"><table border="0" summary="Warning">
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<th align="left">Warning</th>
</tr>
<tr><td align="left" valign="top"><p>
        This library is not accepted to Boost, it is currrently waiting for review.
      </p></td></tr>
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<td align="left"><p><small>Last revised: August 14, 2012 at 12:00:03 GMT</small></p></td>
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