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<h1>Boost Exception</h1>
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<!-- Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc. -->
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<div class="RenoIncludeDIV"><div class="RenoAutoDIV"><h3>exception_ptr</h3>
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<div class="RenoIncludeDIV"><p><span class="RenoEscape">&#35;<!--<wiki>`&#35;</wiki>--></span>include &lt;<span class="RenoLink"><a href="boost_exception_ptr_hpp.html">boost/exception_ptr.hpp</a></span>&gt;</p>
<pre>namespace
boost
    {
<span class="RenoIncludeSPAN">    typedef ---unspecified--- <span class="RenoLink">exception_ptr</span>;</span>
    }</pre>
</div><p>The <span class="RenoLink">exception_ptr</span> type can be used to refer to a copy of an exception object. It is Default Constructible, Copy Constructible, Assignable and Equality Comparable; <span class="RenoLink">exception_ptr</span>'s operations do not throw.</p>
<p>The referenced object remains valid at least as long as there is an <span class="RenoLink">exception_ptr</span> object that refers to it.</p>
<p>Two instances of <span class="RenoLink">exception_ptr</span> are equivalent and compare equal if and only if they refer to the same exception.</p>
<p>The default constructor of <span class="RenoLink">exception_ptr</span> produces the null value of the type. The null value is equivalent only to itself.</p>
<h4>Thread safety:</h4>
<p>The <span class="RenoLink">exception_ptr</span> type is "as thread-safe as built-in types":</p>
<div><ul><li> An <span class="RenoLink">exception_ptr</span> instance can be "read" simultaneously by multiple threads</li>
<li> Different <span class="RenoLink">exception_ptr</span> instances can be "written to" simultaneously by multiple threads, even when these instances refer to the same exception object</li>
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<p>All other simultaneous accesses result in undefined behavior.</p>
<h4>Nesting of exceptions:</h4>
<p>An <span class="RenoLink">exception_ptr</span> can be added as <span class="RenoLink"><a href="error_info.html">error_info</a></span> to any boost::<span class="RenoLink"><a href="exception.html">exception</a></span>. This is a convenient way to nest exceptions. There is no limit on the depth of the nesting, however cyclic references result in undefined behavior.</p>
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See also: <span class="RenoPageList"><a href="boost-exception.html">Boost Exception</a>&nbsp;| <a href="boost_exception_errinfo_nested_exception_hpp.html">boost/exception/errinfo_nested_exception.hpp</a>&nbsp;| <a href="boost_exception_ptr_hpp.html">boost/exception_ptr.hpp</a>&nbsp;| <a href="copy_exception.html">copy_exception</a>&nbsp;| <a href="current_exception.html">current_exception</a>&nbsp;| <a href="diagnostic_information.html">diagnostic_information</a>&nbsp;| <a href="enable_current_exception.html">enable_current_exception</a>&nbsp;| <a href="original_exception_type.html">original_exception_type</a>&nbsp;| <a href="rethrow_exception.html">rethrow_exception</a>&nbsp;| <a href="throw_exception.html">throw_exception</a>&nbsp;| <a href="unknown_exception.html">unknown_exception</a></span>
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<!-- Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc. -->
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