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| <h1>assert.hpp</h1> |
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| <td colspan="2" height="64"> </td> |
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| <p> |
| <a href="#BOOST_ASSERT">BOOST_ASSERT</a><br /> |
| <a href="#BOOST_ASSERT_MSG">BOOST_ASSERT_MSG</a><br /> |
| <a href="#BOOST_VERIFY">BOOST_VERIFY</a><br /> |
| <a href="#BOOST_VERIFY_MSG">BOOST_VERIFY_MSG</a><br /> |
| </p> |
| |
| <h2><a name="BOOST_ASSERT">BOOST_ASSERT</a></h2> |
| <p> |
| The header <code><boost/assert.hpp></code> defines the macro <code>BOOST_ASSERT</code>, |
| which is similar to the standard <code>assert</code> macro defined in <code><cassert></code>. |
| The macro is intended to be used in both Boost libraries and user |
| code. |
| </p> |
| <p>• By default, <code>BOOST_ASSERT(expr)</code> expands to <code>assert(expr)</code>.</p> |
| <p>• If the macro <code>BOOST_DISABLE_ASSERTS</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_ASSERT(expr)</code> expands to <code>((void)0)</code>, regardless of whether |
| the macro <code>NDEBUG</code> is defined. This allows users to selectively disable <code>BOOST_ASSERT</code> without |
| affecting the definition of the standard <code>assert</code>.</p> |
| <p>• If the macro <code>BOOST_ENABLE_ASSERT_HANDLER</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_ASSERT(expr)</code> expands to</p> |
| <blockquote> |
| <pre>(<a href="../config/doc/html/boost_config/boost_macro_reference.html#boost_config.boost_macro_reference.boost_helper_macros">BOOST_LIKELY</a>(!!(expr))? ((void)0): ::boost::assertion_failed(#expr, <a href="current_function.html">BOOST_CURRENT_FUNCTION</a>, __FILE__, __LINE__))</pre> |
| </blockquote> |
| <p>That is, it evaluates <code>expr</code> and if it's false, calls <code>::boost::assertion_failed(#expr, BOOST_CURRENT_FUNCTION, __FILE__, __LINE__)</code>. |
| This is true regardless of whether <code>NDEBUG</code> is defined.</p> |
| <p><code>boost::assertion_failed</code> is declared in <code><boost/assert.hpp></code> as</p> |
| <blockquote> |
| <pre>namespace boost |
| { |
| void assertion_failed(char const * expr, char const * function, char const * file, long line); |
| } |
| </pre> |
| </blockquote> |
| <p>but it is never defined. The user is expected to supply an appropriate |
| definition.</p> |
| <p>• If the macro <code>BOOST_ENABLE_ASSERT_DEBUG_HANDLER</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_ASSERT(expr)</code> expands to <code>((void)0)</code> when <code>NDEBUG</code> is |
| defined. Otherwise the behavior is as if <code>BOOST_ENABLE_ASSERT_HANDLER</code> has been defined.</p> |
| <p>As is the case with <code><cassert></code>, <code><boost/assert.hpp></code> |
| can be included multiple times in a single translation unit. <code>BOOST_ASSERT</code> |
| will be redefined each time as specified above.</p> |
| |
| <h2><a name="BOOST_ASSERT_MSG">BOOST_ASSERT_MSG</a></h2> |
| <p> |
| The macro <code>BOOST_ASSERT_MSG</code> is similar to <code>BOOST_ASSERT</code>, but it takes an additional argument, |
| a character literal, supplying an error message.</p> |
| <p>• By default, <code>BOOST_ASSERT_MSG(expr,msg)</code> expands to <code>assert((expr)&&(msg))</code>.</p> |
| <p>• If the macro <code>BOOST_DISABLE_ASSERTS</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_ASSERT_MSG(expr,msg)</code> expands to <code>((void)0)</code>, regardless of whether |
| the macro <code>NDEBUG</code> is defined.</p> |
| <p>• If the macro <code>BOOST_ENABLE_ASSERT_HANDLER</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_ASSERT_MSG(expr,msg)</code> expands to</p> |
| <blockquote> |
| <pre>(<a href="../config/doc/html/boost_config/boost_macro_reference.html#boost_config.boost_macro_reference.boost_helper_macros">BOOST_LIKELY</a>(!!(expr))? ((void)0): ::boost::assertion_failed_msg(#expr, msg, <a href="current_function.html">BOOST_CURRENT_FUNCTION</a>, __FILE__, __LINE__))</pre> |
| </blockquote> |
| <p>This is true regardless of whether <code>NDEBUG</code> is defined.</p> |
| <p><code>boost::assertion_failed_msg</code> is declared in <code><boost/assert.hpp></code> as</p> |
| <blockquote> |
| <pre>namespace boost |
| { |
| void assertion_failed_msg(char const * expr, char const * msg, char const * function, char const * file, long line); |
| } |
| </pre> |
| </blockquote> |
| <p>but it is never defined. The user is expected to supply an appropriate |
| definition.</p> |
| <p>• If the macro <code>BOOST_ENABLE_ASSERT_DEBUG_HANDLER</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_ASSERT_MSG(expr)</code> expands to <code>((void)0)</code> when <code>NDEBUG</code> is |
| defined. Otherwise the behavior is as if <code>BOOST_ENABLE_ASSERT_HANDLER</code> has been defined.</p> |
| <p>As is the case with <code><cassert></code>, <code><boost/assert.hpp></code> |
| can be included multiple times in a single translation unit. <code>BOOST_ASSERT_MSG</code> |
| will be redefined each time as specified above.</p> |
| |
| <h2><a name="BOOST_VERIFY">BOOST_VERIFY</a></h2> |
| <p>The macro <code>BOOST_VERIFY</code> has the same behavior as <code>BOOST_ASSERT</code>, except that |
| the expression that is passed to <code>BOOST_VERIFY</code> is always |
| evaluated. This is useful when the asserted expression has desirable side |
| effects; it can also help suppress warnings about unused variables when the |
| only use of the variable is inside an assertion.</p> |
| <p>• If the macro <code>BOOST_DISABLE_ASSERTS</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_VERIFY(expr)</code> expands to <code>((void)(expr))</code>.</p> |
| <p>• If the macro <code>BOOST_ENABLE_ASSERT_HANDLER</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_VERIFY(expr)</code> expands to <code>BOOST_ASSERT(expr)</code>.</p> |
| <p>• Otherwise, <code>BOOST_VERIFY(expr)</code> expands to <code>((void)(expr))</code> when <code>NDEBUG</code> is |
| defined, to <code>BOOST_ASSERT(expr)</code> when it's not.</p> |
| <h2><a name="BOOST_VERIFY_MSG">BOOST_VERIFY_MSG</a></h2> |
| <p>The macro <code>BOOST_VERIFY_MSG</code> is similar to <code>BOOST_VERIFY</code>, with an additional parameter, an error message.</p> |
| <p>• If the macro <code>BOOST_DISABLE_ASSERTS</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_VERIFY_MSG(expr,msg)</code> expands to <code>((void)(expr))</code>.</p> |
| <p>• If the macro <code>BOOST_ENABLE_ASSERT_HANDLER</code> is defined when <code><boost/assert.hpp></code> |
| is included, <code>BOOST_VERIFY_MSG(expr,msg)</code> expands to <code>BOOST_ASSERT_MSG(expr,msg)</code>.</p> |
| <p>• Otherwise, <code>BOOST_VERIFY_MSG(expr,msg)</code> expands to <code>((void)(expr))</code> when <code>NDEBUG</code> is |
| defined, to <code>BOOST_ASSERT_MSG(expr,msg)</code> when it's not.</p> |
| <hr /> |
| <p> |
| <small>Copyright © 2002, 2007, 2014 by Peter Dimov. Copyright © 2011 |
| by Beman Dawes. Distributed under the Boost Software |
| License, Version 1.0. See accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> |
| or copy at <a href="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>.</small></p> |
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