boost_1_45_0/libs/utility/checked_delete.html

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					<h1>checked_delete.hpp</h1>
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		<p>
			The header <STRONG>&lt;boost/checked_delete.hpp&gt;</STRONG> defines two 
			function templates, <STRONG>checked_delete</STRONG> and <STRONG>checked_array_delete</STRONG>, 
			and two class templates, <STRONG>checked_deleter</STRONG> and <STRONG>checked_array_deleter</STRONG>.
		</p>
		<P>The C++ Standard allows, in 5.3.5/5, pointers to incomplete class types to be 
			deleted with a <EM>delete-expression</EM>. When the class has a non-trivial 
			destructor, or a class-specific operator delete, the behavior is undefined. 
			Some compilers issue a warning when an incomplete type is deleted, but 
			unfortunately, not all do, and programmers sometimes ignore or disable 
			warnings.</P>
		<P>A particularly troublesome case is when a smart pointer's destructor, such as <STRONG>
				boost::scoped_ptr&lt;T&gt;::~scoped_ptr</STRONG>, is instantiated with an 
			incomplete type. This can often lead to silent, hard to track failures.</P>
		<P>The supplied function and class templates can be used to prevent these problems, 
			as they require a complete type, and cause a compilation error otherwise.</P>
		<h3><a name="Synopsis">Synopsis</a></h3>
		<pre>
namespace boost
{

template&lt;class T&gt; void checked_delete(T * p);
template&lt;class T&gt; void checked_array_delete(T * p);
template&lt;class T&gt; struct checked_deleter;
template&lt;class T&gt; struct checked_array_deleter;

}
</pre>
		<h3>checked_delete</h3>
		<h4><a name="checked_delete">template&lt;class T&gt; void checked_delete(T * p);</a></h4>
		<blockquote>
			<p>
				<b>Requires:</b> <b>T</b> must be a complete type. The expression <tt>delete p</tt>
				must be well-formed.
			</p>
			<p>
				<b>Effects:</b> <tt>delete p;</tt>
			</p>
		</blockquote>
		<h3>checked_array_delete</h3>
		<h4><a name="checked_array_delete">template&lt;class T&gt; void checked_array_delete(T 
				* p);</a></h4>
		<blockquote>
			<p>
				<b>Requires:</b> <b>T</b> must be a complete type. The expression <tt>delete [] p</tt>
				must be well-formed.
			</p>
			<p>
				<b>Effects:</b> <tt>delete [] p;</tt>
			</p>
		</blockquote>
		<h3>checked_deleter</h3>
		<pre>
template&lt;class T&gt; struct checked_deleter
{
    typedef void result_type;
    typedef T * argument_type;
    void operator()(T * p) const;
};
</pre>
		<h4>void checked_deleter&lt;T&gt;::operator()(T * p) const;</h4>
		<blockquote>
			<p>
				<b>Requires:</b> <b>T</b> must be a complete type. The expression <tt>delete p</tt>
				must be well-formed.
			</p>
			<p>
				<b>Effects:</b> <tt>delete p;</tt>
			</p>
		</blockquote>
		<h3>checked_array_deleter</h3>
		<pre>
template&lt;class T&gt; struct checked_array_deleter
{
    typedef void result_type;
    typedef T * argument_type;
    void operator()(T * p) const;
};
</pre>
		<h4>void checked_array_deleter&lt;T&gt;::operator()(T * p) const;</h4>
		<blockquote>
			<p>
				<b>Requires:</b> <b>T</b> must be a complete type. The expression <tt>delete [] p</tt>
				must be well-formed.
			</p>
			<p>
				<b>Effects:</b> <tt>delete [] p;</tt>
			</p>
		</blockquote>
		<h3><a name="Acknowledgements">Acknowledgements</a></h3>
		<p>
			The function templates <STRONG>checked_delete</STRONG> and <STRONG>checked_array_delete</STRONG>
			were originally part of <STRONG>&lt;boost/utility.hpp&gt;</STRONG>, and the 
			documentation acknowledged Beman Dawes, Dave Abrahams, Vladimir Prus, Rainer 
			Deyke, John Maddock, and others as contributors.
		</p>
		<p>
			<br>
			<small>Copyright © 2002 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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