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<li class="level2"><div class="li"><span class="li"><a href="#typeinfo" class="toc">typeinfo</a></span></div>
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<li class="level3"><div class="li"><span class="li"><a href="#type_info" class="toc">type_info</a></span></div></li>
<li class="level3"><div class="li"><span class="li"><a href="#bad_cast" class="toc">bad_cast</a></span></div></li>
<li class="level3"><div class="li"><span class="li"><a href="#bad_typeid" class="toc">bad_typeid</a></span></div></li></ul>
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<h2><a name="typeinfo" id="typeinfo">typeinfo</a></h2>
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<p>
The <code>&lt;typeinfo&gt;</code> header provides class definitions used for run-time type information.

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<h3><a name="type_info" id="type_info">type_info</a></h3>
<div class="level3">
<pre class="cpp code cpp" style="font-family:monospace;"><span class="kw2">class</span> type_info
<span class="br0">&#123;</span>
<span class="kw2">public</span><span class="sy4">:</span>
    <span class="kw2">virtual</span> ~type_info<span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    <span class="kw4">bool</span> operator<span class="sy1">==</span><span class="br0">&#40;</span><span class="kw4">const</span> type_info<span class="sy3">&amp;</span>  rhs <span class="br0">&#41;</span> <span class="kw4">const</span><span class="sy4">;</span>
    <span class="kw4">bool</span> operator<span class="sy3">!</span><span class="sy1">=</span><span class="br0">&#40;</span><span class="kw4">const</span> type_info<span class="sy3">&amp;</span>  rhs <span class="br0">&#41;</span> <span class="kw4">const</span><span class="sy4">;</span>
    <span class="kw4">bool</span> before<span class="br0">&#40;</span><span class="kw4">const</span> type_info<span class="sy3">&amp;</span>  rhs <span class="br0">&#41;</span> <span class="kw4">const</span><span class="sy4">;</span>
    <span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> name<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw4">const</span><span class="sy4">;</span>
<span class="kw2">private</span><span class="sy4">:</span>
    type_info<span class="br0">&#40;</span><span class="kw4">const</span> type_info<span class="sy3">&amp;</span>  rhs <span class="br0">&#41;</span><span class="sy4">;</span>
    type_info<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">&#40;</span><span class="kw4">const</span> type_info<span class="sy3">&amp;</span>  rhs <span class="br0">&#41;</span><span class="sy4">;</span>
<span class="br0">&#125;</span><span class="sy4">;</span></pre>
<p>

Class type_info is the type of the object that is returned by the <a href="../keywords/typeid.html" class="wikilink1" title="keywords:typeid">typeid</a> expression. It provides implementation specific type information. The type name provided and collation sequence are implementation defined, and may vary between programs even when using the same compiler.
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<h3><a name="bad_cast" id="bad_cast">bad_cast</a></h3>
<div class="level3">
<pre class="cpp code cpp" style="font-family:monospace;"><span class="kw2">class</span> bad_cast <span class="sy4">:</span> <span class="kw2">public</span> exception
<span class="br0">&#123;</span>
<span class="kw2">public</span><span class="sy4">:</span>
    bad_cast<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    bad_cast<span class="br0">&#40;</span><span class="kw4">const</span> bad_cast<span class="sy3">&amp;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    bad_cast<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">&#40;</span><span class="kw4">const</span> bad_cast<span class="sy3">&amp;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    <span class="kw2">virtual</span> ~bad_cast<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    <span class="kw2">virtual</span> <span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> what<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw4">const</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
<span class="br0">&#125;</span><span class="sy4">;</span></pre>
<p>

Class bad_cast is the type of the object that is thrown by an invalid <a href="../keywords/dynamic_cast.html" class="wikilink1" title="keywords:dynamic_cast">dynamic_cast</a> expression. The standard explicitly defines it will be thrown when a cast to a reference type fails.
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<h3><a name="bad_typeid" id="bad_typeid">bad_typeid</a></h3>
<div class="level3">
<pre class="cpp code cpp" style="font-family:monospace;"><span class="kw2">class</span> bad_typeid <span class="sy4">:</span> <span class="kw2">public</span> exception
<span class="br0">&#123;</span>
<span class="kw2">public</span><span class="sy4">:</span>
    bad_typeid<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    bad_typeid<span class="br0">&#40;</span><span class="kw4">const</span> bad_typeid<span class="sy3">&amp;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    bad_typeid<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">&#40;</span><span class="kw4">const</span> bad_typeid<span class="sy3">&amp;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    <span class="kw2">virtual</span> ~bad_typeid<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
    <span class="kw2">virtual</span> <span class="kw4">const</span> <span class="kw4">char</span><span class="sy2">*</span> what<span class="br0">&#40;</span><span class="br0">&#41;</span> <span class="kw4">const</span> <span class="kw1">throw</span><span class="br0">&#40;</span><span class="br0">&#41;</span><span class="sy4">;</span>
<span class="br0">&#125;</span><span class="sy4">;</span></pre>
<p>

Class bad_typeid is the type of the object that is thrown if the argument in a <a href="../keywords/typeid.html" class="wikilink1" title="keywords:typeid">typeid</a> expression is null.

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