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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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        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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<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/reference.html">Reference</a></span></dt>
<dt><span class="section"><a href="boost_typeindex/performance.html">Performance</a></span></dt>
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<div class="section boost_typeindex_motivation">
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<a name="boost_typeindex.motivation"></a><a class="link" href="index.html#boost_typeindex.motivation" title="Motivation">Motivation</a>
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<p>
      Sometimes getting and storing at runtime information about template type is
      required. For such cases usually used 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>.
      And that is the point, where problems strat: * <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)
      * <code class="computeroutput"><span class="keyword">typeid</span><span class="special">(</span><span class="identifier">T</span><span class="special">)</span></code> strips
      const, volatile and references from type * 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> across shared libraries * 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> do not
      strip const, volatile and references * only a few STLs have <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">type_index</span></code>
      implementation * no easy way to store type info without stripping const, volatile
      and references * no nice and portable way to get human readable type name
    </p>
<p>
      Boost.TypeIndex was designed to work around those issues.
    </p>
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<td align="left"><p><small>Last revised: June 03, 2012 at 10:37:07 GMT</small></p></td>
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