1<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.0 Strict//EN' 2'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd'> 3<html xmlns='http://www.w3.org/1999/xhtml' xml:lang='en' lang='en'> 4<head> 5 <meta http-equiv='Content-Type' content='text/html; charset=utf-8'/> 6 <title>exception_ptr</title> 7 <link href='reno.css' type='text/css' rel='stylesheet'/> 8</head> 9<body> 10<div class="body-0"> 11<div class="body-1"> 12<div class="body-2"> 13<div> 14<div id="boost_logo"> 15<a href="http://www.boost.org"><img style="border:0" src="../../../boost.png" alt="Boost" width="277" height="86"/></a> 16</div> 17<h1>Boost Exception</h1> 18</div> 19<!-- Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc. --> 20<!-- Distributed under the Boost Software License, Version 1.0. (See accompanying --> 21<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) --> 22<div class="RenoIncludeDIV"><div class="RenoAutoDIV"><h3>exception_ptr</h3> 23</div> 24<div class="RenoIncludeDIV"><p><span class="RenoEscape">#<!--<wiki>`#</wiki>--></span>include <<span class="RenoLink"><a href="boost_exception_ptr_hpp.html">boost/exception_ptr.hpp</a></span>></p> 25<pre>namespace 26boost 27 { 28<span class="RenoIncludeSPAN"> typedef ---unspecified--- <span class="RenoLink">exception_ptr</span>;</span> 29 }</pre> 30</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> 31<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> 32<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> 33<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> 34<h4>Thread safety:</h4> 35<p>The <span class="RenoLink">exception_ptr</span> type is "as thread-safe as built-in types":</p> 36<div><ul><li> An <span class="RenoLink">exception_ptr</span> instance can be "read" simultaneously by multiple threads</li> 37<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> 38</ul></div> 39<p>All other simultaneous accesses result in undefined behavior.</p> 40<h4>Nesting of exceptions:</h4> 41<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> 42</div><div class="RenoAutoDIV"><div class="RenoHR"><hr/></div> 43See also: <span class="RenoPageList"><a href="boost-exception.html">Boost Exception</a> | <a href="boost_exception_errinfo_nested_exception_hpp.html">boost/exception/errinfo_nested_exception.hpp</a> | <a href="boost_exception_ptr_hpp.html">boost/exception_ptr.hpp</a> | <a href="copy_exception.html">copy_exception</a> | <a href="current_exception.html">current_exception</a> | <a href="diagnostic_information.html">diagnostic_information</a> | <a href="enable_current_exception.html">enable_current_exception</a> | <a href="original_exception_type.html">original_exception_type</a> | <a href="rethrow_exception.html">rethrow_exception</a> | <a href="throw_exception.html">throw_exception</a> | <a href="unknown_exception.html">unknown_exception</a></span> 44</div> 45<!-- Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc. --> 46<!-- Distributed under the Boost Software License, Version 1.0. (See accompanying --> 47<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) --> 48<div id="footer"> 49<p> 50<a class="logo" href="http://jigsaw.w3.org/css-validator/check/referer"><img class="logo_pic" src="valid-css.png" alt="Valid CSS" height="31" width="88"/></a> 51<a class="logo" href="http://validator.w3.org/check?uri=referer"><img class="logo_pic" src="valid-xhtml.png" alt="Valid XHTML 1.0" height="31" width="88"/></a> 52<small>Copyright (c) 2006-2009 by Emil Dotchevski and Reverge Studios, Inc.<br/> 53Distributed under the <a href="http://www.boost.org/LICENSE_1_0.txt">Boost Software License, Version 1.0</a>.</small> 54</p> 55</div> 56</div> 57</div> 58</div> 59</body> 60</html> 61
