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  26 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
  27 <a name="core.checked_delete"></a><a class="link" href="checked_delete.html" title="checked_delete">checked_delete</a>
  28 </h2></div></div></div>
  29 <div class="toc"><dl class="toc">
  30 <dt><span class="section"><a href="checked_delete.html#core.checked_delete.overview">Overview</a></span></dt>
  31 <dt><span class="section"><a href="checked_delete.html#core.checked_delete.synopsis">Synopsis</a></span></dt>
  32 <dt><span class="section"><a href="checked_delete.html#core.checked_delete.checked_delete">checked_delete</a></span></dt>
  33 <dt><span class="section"><a href="checked_delete.html#core.checked_delete.checked_array_delete">checked_array_delete</a></span></dt>
  34 <dt><span class="section"><a href="checked_delete.html#core.checked_delete.checked_deleter">checked_deleter</a></span></dt>
  35 <dt><span class="section"><a href="checked_delete.html#core.checked_delete.checked_array_deleter">checked_array_deleter</a></span></dt>
  36 <dt><span class="section"><a href="checked_delete.html#core.checked_delete.acknowledgements">Acknowledgements</a></span></dt>
  37 </dl></div>
  38 <div class="simplesect">
  39 <div class="titlepage"><div><div><h3 class="title">
  40 <a name="idp81391888"></a>Authors</h3></div></div></div>
  41 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
  42 <li class="listitem">
  43           Beman Dawes
  44         </li>
  45 <li class="listitem">
  46           Dave Abrahams
  47         </li>
  48 <li class="listitem">
  49           Vladimir Prus
  50         </li>
  51 <li class="listitem">
  52           Rainer Deyke
  53         </li>
  54 <li class="listitem">
  55           John Maddock
  56         </li>
  57 </ul></div>
  58 </div>
  59 <div class="section">
  60 <div class="titlepage"><div><div><h3 class="title">
  61 <a name="core.checked_delete.overview"></a><a class="link" href="checked_delete.html#core.checked_delete.overview" title="Overview">Overview</a>
  62 </h3></div></div></div>
  63 <p>
  64         The header <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">checked_delete</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
  65         defines two function templates, <code class="computeroutput"><span class="identifier">checked_delete</span></code>
  66         and <code class="computeroutput"><span class="identifier">checked_array_delete</span></code>,
  67         and two class templates, <code class="computeroutput"><span class="identifier">checked_deleter</span></code>
  68         and <code class="computeroutput"><span class="identifier">checked_array_deleter</span></code>.
  69       </p>
  70 <p>
  71         The C++ Standard allows, in 5.3.5/5, pointers to incomplete class types to
  72         be deleted with a delete-expression. When the class has a non-trivial destructor,
  73         or a class-specific operator delete, the behavior is undefined. Some compilers
  74         issue a warning when an incomplete type is deleted, but unfortunately, not
  75         all do, and programmers sometimes ignore or disable warnings.
  76       </p>
  77 <p>
  78         A particularly troublesome case is when a smart pointer's destructor, such
  79         as <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">scoped_ptr</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;::~</span><span class="identifier">scoped_ptr</span></code>, is instantiated with an incomplete
  80         type. This can often lead to silent, hard to track failures.
  81       </p>
  82 <p>
  83         The supplied function and class templates can be used to prevent these problems,
  84         as they require a complete type, and cause a compilation error otherwise.
  85       </p>
  86 </div>
  87 <div class="section">
  88 <div class="titlepage"><div><div><h3 class="title">
  89 <a name="core.checked_delete.synopsis"></a><a class="link" href="checked_delete.html#core.checked_delete.synopsis" title="Synopsis">Synopsis</a>
  90 </h3></div></div></div>
  91 <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span>
  92 <span class="special">{</span>
  93     <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">void</span> <span class="identifier">checked_delete</span><span class="special">(</span><span class="identifier">T</span> <span class="special">*</span> <span class="identifier">p</span><span class="special">);</span>
  94     <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">void</span> <span class="identifier">checked_array_delete</span><span class="special">(</span><span class="identifier">T</span> <span class="special">*</span> <span class="identifier">p</span><span class="special">);</span>
  95     <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">checked_deleter</span><span class="special">;</span>
  96     <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">checked_array_deleter</span><span class="special">;</span>
  97 <span class="special">}</span>
  98 </pre>
  99 </div>
 100 <div class="section">
 101 <div class="titlepage"><div><div><h3 class="title">
 102 <a name="core.checked_delete.checked_delete"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_delete" title="checked_delete">checked_delete</a>
 103 </h3></div></div></div>
 104 <div class="section">
 105 <div class="titlepage"><div><div><h4 class="title">
 106 <a name="core.checked_delete.checked_delete.template_class_t_void_checked_de"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_delete.template_class_t_void_checked_de" title="template&lt;class T&gt; void checked_delete(T * p);">template&lt;class
 107         T&gt; void checked_delete(T * p);</a>
 108 </h4></div></div></div>
 109 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 110 <li class="listitem">
 111               <span class="bold"><strong>Requires:</strong></span> <code class="computeroutput"><span class="identifier">T</span></code>
 112               must be a complete type. The expression <code class="computeroutput"><span class="keyword">delete</span>
 113               <span class="identifier">p</span></code> must be well-formed.
 114             </li>
 115 <li class="listitem">
 116               <span class="bold"><strong>Effects:</strong></span> <code class="computeroutput"><span class="keyword">delete</span>
 117               <span class="identifier">p</span><span class="special">;</span></code>
 118             </li>
 119 </ul></div>
 120 </div>
 121 </div>
 122 <div class="section">
 123 <div class="titlepage"><div><div><h3 class="title">
 124 <a name="core.checked_delete.checked_array_delete"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_array_delete" title="checked_array_delete">checked_array_delete</a>
 125 </h3></div></div></div>
 126 <div class="section">
 127 <div class="titlepage"><div><div><h4 class="title">
 128 <a name="core.checked_delete.checked_array_delete.template_class_t_void_checked_ar"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_array_delete.template_class_t_void_checked_ar" title="template&lt;class T&gt; void checked_array_delete(T * p);">template&lt;class
 129         T&gt; void checked_array_delete(T * p);</a>
 130 </h4></div></div></div>
 131 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 132 <li class="listitem">
 133               <span class="bold"><strong>Requires:</strong></span> <code class="computeroutput"><span class="identifier">T</span></code>
 134               must be a complete type. The expression <code class="computeroutput"><span class="keyword">delete</span>
 135               <span class="special">[]</span> <span class="identifier">p</span></code>
 136               must be well-formed.
 137             </li>
 138 <li class="listitem">
 139               <span class="bold"><strong>Effects:</strong></span> <code class="computeroutput"><span class="keyword">delete</span>
 140               <span class="special">[]</span> <span class="identifier">p</span><span class="special">;</span></code>
 141             </li>
 142 </ul></div>
 143 </div>
 144 </div>
 145 <div class="section">
 146 <div class="titlepage"><div><div><h3 class="title">
 147 <a name="core.checked_delete.checked_deleter"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_deleter" title="checked_deleter">checked_deleter</a>
 148 </h3></div></div></div>
 149 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">checked_deleter</span>
 150 <span class="special">{</span>
 151     <span class="keyword">typedef</span> <span class="keyword">void</span> <span class="identifier">result_type</span><span class="special">;</span>
 152     <span class="keyword">typedef</span> <span class="identifier">T</span> <span class="special">*</span> <span class="identifier">argument_type</span><span class="special">;</span>
 153     <span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">T</span> <span class="special">*</span> <span class="identifier">p</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
 154 <span class="special">};</span>
 155 </pre>
 156 <div class="section">
 157 <div class="titlepage"><div><div><h4 class="title">
 158 <a name="core.checked_delete.checked_deleter.void_checked_deleter_t_operator_"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_deleter.void_checked_deleter_t_operator_" title="void checked_deleter&lt;T&gt;::operator()(T * p) const;">void
 159         checked_deleter&lt;T&gt;::operator()(T * p) const;</a>
 160 </h4></div></div></div>
 161 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 162 <li class="listitem">
 163               <span class="bold"><strong>Requires:</strong></span> <code class="computeroutput"><span class="identifier">T</span></code>
 164               must be a complete type. The expression <code class="computeroutput"><span class="keyword">delete</span>
 165               <span class="identifier">p</span></code> must be well-formed.
 166             </li>
 167 <li class="listitem">
 168               <span class="bold"><strong>Effects:</strong></span> <code class="computeroutput"><span class="keyword">delete</span>
 169               <span class="identifier">p</span><span class="special">;</span></code>
 170             </li>
 171 </ul></div>
 172 </div>
 173 </div>
 174 <div class="section">
 175 <div class="titlepage"><div><div><h3 class="title">
 176 <a name="core.checked_delete.checked_array_deleter"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_array_deleter" title="checked_array_deleter">checked_array_deleter</a>
 177 </h3></div></div></div>
 178 <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span> <span class="keyword">struct</span> <span class="identifier">checked_array_deleter</span>
 179 <span class="special">{</span>
 180     <span class="keyword">typedef</span> <span class="keyword">void</span> <span class="identifier">result_type</span><span class="special">;</span>
 181     <span class="keyword">typedef</span> <span class="identifier">T</span> <span class="special">*</span> <span class="identifier">argument_type</span><span class="special">;</span>
 182     <span class="keyword">void</span> <span class="keyword">operator</span><span class="special">()(</span><span class="identifier">T</span> <span class="special">*</span> <span class="identifier">p</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
 183 <span class="special">};</span>
 184 </pre>
 185 <div class="section">
 186 <div class="titlepage"><div><div><h4 class="title">
 187 <a name="core.checked_delete.checked_array_deleter.void_checked_array_deleter_t_ope"></a><a class="link" href="checked_delete.html#core.checked_delete.checked_array_deleter.void_checked_array_deleter_t_ope" title="void checked_array_deleter&lt;T&gt;::operator()(T * p) const;">void
 188         checked_array_deleter&lt;T&gt;::operator()(T * p) const;</a>
 189 </h4></div></div></div>
 190 <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
 191 <li class="listitem">
 192               <span class="bold"><strong>Requires:</strong></span> <code class="computeroutput"><span class="identifier">T</span></code>
 193               must be a complete type. The expression <code class="computeroutput"><span class="keyword">delete</span>
 194               <span class="special">[]</span> <span class="identifier">p</span></code>
 195               must be well-formed.
 196             </li>
 197 <li class="listitem">
 198               <span class="bold"><strong>Effects:</strong></span> <code class="computeroutput"><span class="keyword">delete</span>
 199               <span class="special">[]</span> <span class="identifier">p</span><span class="special">;</span></code>
 200             </li>
 201 </ul></div>
 202 </div>
 203 </div>
 204 <div class="section">
 205 <div class="titlepage"><div><div><h3 class="title">
 206 <a name="core.checked_delete.acknowledgements"></a><a class="link" href="checked_delete.html#core.checked_delete.acknowledgements" title="Acknowledgements">Acknowledgements</a>
 207 </h3></div></div></div>
 208 <p>
 209         The function templates <code class="computeroutput"><span class="identifier">checked_delete</span></code>
 210         and <code class="computeroutput"><span class="identifier">checked_array_delete</span></code>
 211         were originally part of <code class="computeroutput"><span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">utility</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>,
 212         and the documentation acknowledged Beman Dawes, Dave Abrahams, Vladimir Prus,
 213         Rainer Deyke, John Maddock, and others as contributors.
 214       </p>
 215 </div>
 216 </div>
 217 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 218 <td align="left"></td>
 219 <td align="right"><div class="copyright-footer">Copyright &#169; 2014 Peter Dimov<br>Copyright &#169; 2014 Glen Fernandes<br>Copyright &#169; 2014 Andrey Semashev<p>
 220         Distributed under the <a href="http://boost.org/LICENSE_1_0.txt" target="_top">Boost
 221         Software License, Version 1.0</a>.
 222       </p>
 223 </div></td>
 224 </tr></table>
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