<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.0 Strict//EN' 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd'> <html xmlns='http://www.w3.org/1999/xhtml' xml:lang='en' lang='en'> <head> <meta http-equiv='Content-Type' content='text/html; charset=utf-8'/> <title>diagnostic_information</title> <link href='reno.css' type='text/css' rel='stylesheet'/> </head> <body> <div class="body-0"> <div class="body-1"> <div class="body-2"> <div> <div id="boost_logo"> <a href="http://www.boost.org"><img style="border:0" src="../../../boost.png" alt="Boost" width="277" height="86"/></a> </div> <h1>Boost Exception</h1> </div> <!-- 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) --> <div class="RenoIncludeDIV"><div class="RenoAutoDIV"><h3>diagnostic_information</h3> </div> <div class="RenoIncludeDIV"><p><span class="RenoEscape">#<!--<wiki>`#</wiki>--></span>include <<span class="RenoLink"><a href="boost_exception_diagnostic_information_hpp.html">boost/exception/diagnostic_information.hpp</a></span>><span class="RenoBR"> </span><br/><span class="RenoEscape">#<!--<wiki>`#</wiki>--></span>include <<span class="RenoLink"><a href="boost_exception_ptr_hpp.html">boost/exception_ptr.hpp</a></span>><span class="RenoBR"> </span><br/></p> <pre>namespace boost { <span class="RenoIncludeSPAN"> template <class E> std::string <span class="RenoLink">diagnostic_information</span>( E const & e ); std::string <span class="RenoLink">diagnostic_information</span>( <span class="RenoLink"><a href="exception_ptr.html">exception_ptr</a></span> const & p );</span> }</pre> </div><h4>Returns:</h4> <p>A string value that contains varying amount of implementation-specific diagnostic information about the passed object:</p> <div><ul><li>If E can be statically converted to boost::<span class="RenoLink"><a href="exception.html">exception</a></span>, the returned value contains the string representations of all <span class="RenoLink"><a href="error_info.html">error_info</a></span> objects stored in the boost::<span class="RenoLink"><a href="exception.html">exception</a></span> through <span class="RenoLink"><a href="exception_operator_shl.html">operator<<</a></span>, along with other diagnostic information relevant to the exception. If e can be dynamically converted to std::exception, the returned value also contains the what() string.</li> <li>Otherwise, if E can be statically converted to std::exception:<div><ul><li>if e can be dynamically converted to boost::exception, the returned value is the same as if E could be statically converted to boost::<span class="RenoLink"><a href="exception.html">exception</a></span>;</li> <li>otherwise the returned value contains the what() string.</li> </ul></div> </li> <li>Otherwise, the boost::<span class="RenoLink">diagnostic_information</span> template is not available.</li> </ul></div> <p>The string representation of each <span class="RenoLink"><a href="error_info.html">error_info</a></span> object is deduced by a function call that is bound at the time the <span class="RenoLink"><a href="error_info.html">error_info</a></span><Tag,T> template is instantiated. The following overload resolutions are attempted in order:</p> <div><ol><li>Unqualified call to to_string(x), where x is of type <span class="RenoLink"><a href="error_info.html">error_info</a></span><Tag,T> (the return value is expected to be of type std::string.)</li> <li>Unqualified call to to_string(x.<span class="RenoLink"><a href="error_info_value.html">value</a></span>()) (the return value is expected to be of type std::string.)</li> <li>Unqualified call to s << x.<span class="RenoLink"><a href="error_info_value.html">value</a></span>(), where s is a std::ostringstream.</li> </ol></div> <p>The first successfully bound function is used at the time <span class="RenoLink">diagnostic_information</span> is called; if all 3 overload resolutions are unsuccessful, the system is unable to convert the <span class="RenoLink"><a href="error_info.html">error_info</a></span> object to string, and <i>an unspecified stub string value is used without issuing a compile error.</i></p> <p>The <span class="RenoLink"><a href="exception_ptr.html">exception_ptr</a></span> overload of <span class="RenoLink">diagnostic_information</span> is equivalent to:</p> <pre>if( p ) try { <span class="RenoLink"><a href="rethrow_exception.html">rethrow_exception</a></span>(p); } catch(...) { return <span class="RenoLink"><a href="current_exception_diagnostic_information.html">current_exception_diagnostic_information</a></span>(); } else return <unspecified-string-value>;</pre> <h4>Notes:</h4> <div><ul><li>The format of the returned string is unspecified.</li> <li>The returned string is <i>not</i> user-friendly.</li> <li>The returned string may include additional platform-specific diagnostic information.</li> </ul></div> <div class="RenoIncludeDIV"><h4>Example:</h4> <p>this is a possible output from the <span class="RenoLink">diagnostic_information</span> function, as used in <i>libs/exception/example/example_io.cpp:</i></p> <pre>example_io.cpp(70): Throw in function class boost::shared_ptr<struct _iobuf> __cdecl my_fopen(const char *,const char *) Dynamic exception type: class boost::exception_detail::clone_impl<struct fopen_error> std::exception::what: example_io error [struct boost::<span class="RenoLink"><a href="errinfo_api_function.html">errinfo_api_function</a></span>_ *] = fopen [struct boost::<span class="RenoLink"><a href="errinfo_errno.html">errinfo_errno</a></span>_ *] = 2, "No such file or directory" [struct boost::<span class="RenoLink"><a href="errinfo_file_name.html">errinfo_file_name</a></span>_ *] = tmp1.txt [struct boost::<span class="RenoLink"><a href="errinfo_file_open_mode.html">errinfo_file_open_mode</a></span>_ *] = rb</pre> </div></div><div class="RenoAutoDIV"><div class="RenoHR"><hr/></div> See also: <span class="RenoPageList"><a href="BOOST_THROW_EXCEPTION.html">BOOST_THROW_EXCEPTION</a> | <a href="boost-exception.html">Boost Exception</a> | <a href="boost_exception_diagnostic_information_hpp.html">boost/exception/diagnostic_information.hpp</a> | <a href="configuration_macros.html">Configuration Macros</a> | <a href="current_exception_diagnostic_information.html">current_exception_diagnostic_information</a> | <a href="tutorial_diagnostic_information.html">Diagnostic Information</a> | <a href="diagnostic_information_what.html">diagnostic_information_what</a> | <a href="frequently_asked_questions.html">Frequently Asked Questions</a> | <a href="motivation.html">Motivation</a> | <a href="throw_exception.html">throw_exception</a></span> </div> <!-- 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) --> <div id="footer"> <p> <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> <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> <small>Copyright (c) 2006-2009 by Emil Dotchevski and Reverge Studios, Inc.<br/> Distributed under the <a href="http://www.boost.org/LICENSE_1_0.txt">Boost Software License, Version 1.0</a>.</small> </p> </div> </div> </div> </div> </body> </html>