boost_1_45_0/libs/utility/assert.html

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					<h1>assert.hpp</h1>
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		<p>
			The header <STRONG>&lt;boost/assert.hpp&gt;</STRONG> defines the macro <b>BOOST_ASSERT</b>, 
			which is similar to the standard <STRONG>assert</STRONG> macro defined in <STRONG>&lt;cassert&gt;</STRONG>. 
			The macro is intended to be used in Boost libraries.
		</p>
		<P>By default, <tt>BOOST_ASSERT(expr)</tt> is equivalent to <tt>assert(expr)</tt>.</P>
		<P>When the macro <STRONG>BOOST_DISABLE_ASSERTS</STRONG> is defined when <STRONG>&lt;boost/assert.hpp&gt;</STRONG>
			is included, <tt>BOOST_ASSERT(expr)</tt> is defined as <tt>((void)0)</tt>. This 
			allows users to selectively disable <STRONG>BOOST_ASSERT</STRONG> without 
			affecting the definition of the standard <STRONG>assert</STRONG>.</P>
		<P>When the macro <STRONG>BOOST_ENABLE_ASSERT_HANDLER</STRONG> is defined when <STRONG>&lt;boost/assert.hpp&gt;</STRONG>
			is included, <tt>BOOST_ASSERT(expr)</tt> evaluates <b>expr</b> and, if the 
			result is false, evaluates the expression</P>
		<P><tt>::boost::assertion_failed(#expr, <a href="current_function.html">BOOST_CURRENT_FUNCTION</a>, 
				__FILE__, __LINE__)</tt></P>
		<P><STRONG>assertion_failed</STRONG> is declared in <STRONG>&lt;boost/assert.hpp&gt;</STRONG>
			as</P>
		<pre>
namespace boost
{

void assertion_failed(char const * expr, char const * function, char const * file, long line);

}
</pre>
		<p>but it is never defined. The user is expected to supply an appropriate 
			definition.</p>
		<P>As is the case with <STRONG>&lt;cassert&gt;</STRONG>, <STRONG>&lt;boost/assert.hpp&gt;</STRONG>
			can be included multiple times in a single translation unit. <STRONG>BOOST_ASSERT</STRONG>
			will be redefined each time as specified above.</P>
		<p><STRONG>&lt;boost/assert.hpp&gt;</STRONG> also defines the macro <STRONG>BOOST_VERIFY</STRONG>. 
			It has exactly the same behavior as <STRONG>BOOST_ASSERT</STRONG>, except that 
			the expression that is passed to <STRONG>BOOST_VERIFY</STRONG> 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><br>
			<small>Copyright © 2002, 2007 by Peter Dimov. 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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