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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>current_exception</h3> |
| </div> |
| <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> |
| <pre>namespace |
| boost |
| { |
| <span class="RenoIncludeSPAN"> <span class="RenoLink"><a href="exception_ptr.html">exception_ptr</a></span> <span class="RenoLink">current_exception</span>();</span> |
| }</pre> |
| </div><h4>Requirements:</h4> |
| <p>The <span class="RenoLink">current_exception</span> function must not be called outside of a catch block.</p> |
| <p>In addition, to safely copy an exception from one thread to another, if the exception object is copied by <span class="RenoLink">current_exception</span> or <span class="RenoLink"><a href="copy_exception.html">copy_exception</a></span>, the two copies must not have shared state. Exceptions that have value-type semantics (as well as the boost::<span class="RenoLink"><a href="exception.html">exception</a></span> type itself) satisfy this requirement.</p> |
| <h4>Returns:</h4> |
| <div><ul><li> An <span class="RenoLink"><a href="exception_ptr.html">exception_ptr</a></span> that refers to the currently handled exception or a copy of the currently handled exception.</li> |
| <li> If the function needs to allocate memory and the attempt fails, it returns an <span class="RenoLink"><a href="exception_ptr.html">exception_ptr</a></span> that refers to an instance of std::bad_alloc.</li> |
| </ul></div> |
| <h4>Throws:</h4> |
| <p>Nothing.</p> |
| <h4>Notes:</h4> |
| <div><ul><li> It is unspecified whether the return values of two successive calls to <span class="RenoLink">current_exception</span> refer to the same exception object.</li> |
| <li> Correct implementation of <span class="RenoLink">current_exception</span> may require compiler support, unless <span class="RenoLink"><a href="enable_current_exception.html">enable_current_exception</a></span> was used at the time the currently handled exception object was passed to throw. Whenever <span class="RenoLink">current_exception</span> fails to properly copy the current exception object, it returns an <span class="RenoLink"><a href="exception_ptr.html">exception_ptr</a></span> to an object of type that is as close as possible to the original exception type, using <span class="RenoLink"><a href="unknown_exception.html">unknown_exception</a></span> as a final fallback. All such types derive from boost::<span class="RenoLink"><a href="exception.html">exception</a></span>, and:<div><ul><li> if the original exception object derives from boost::<span class="RenoLink"><a href="exception.html">exception</a></span>, then the boost::<span class="RenoLink"><a href="exception.html">exception</a></span> sub-object of the object referred to by the returned <span class="RenoLink"><a href="exception_ptr.html">exception_ptr</a></span> is initialized by the boost::<span class="RenoLink"><a href="exception.html">exception</a></span> copy constructor;</li> |
| <li> if available, the exception contains the std::type_info of the original exception object, accessible through <span class="RenoLink"><a href="get_error_info.html">get_error_info</a></span><<span class="RenoLink"><a href="original_exception_type.html">original_exception_type</a></span>>.</li> |
| </ul></div> |
| </li> |
| </ul></div> |
| </div><div class="RenoAutoDIV"><div class="RenoHR"><hr/></div> |
| See also: <span class="RenoPageList"><a href="boost-exception.html">Boost Exception</a> | <a href="boost_exception_ptr_hpp.html">boost/exception_ptr.hpp</a> | <a href="copy_exception.html">copy_exception</a> | <a href="enable_current_exception.html">enable_current_exception</a> | <a href="frequently_asked_questions.html">Frequently Asked Questions</a> | <a href="original_exception_type.html">original_exception_type</a> | <a href="unknown_exception.html">unknown_exception</a></span> |
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| <!-- Copyright (c) 2006-2009 Emil Dotchevski and Reverge Studios, Inc. --> |
| <!-- Distributed under the Boost Software License, Version 1.0. (See accompanying --> |
| <!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) --> |
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| <small>Copyright (c) 2006-2009 by Emil Dotchevski and Reverge Studios, Inc.<br/> |
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