ceph/src/boost/libs/mpl/doc/refmanual/inherit.html

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   7 <title>The MPL Reference Manual: inherit</title>
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  12 <td class="header-group page-location"><a href="../refmanual.html" class="navigation-link">Front Page</a> / <a href="./metafunctions.html" class="navigation-link">Metafunctions</a> / <a href="./miscellaneous.html" class="navigation-link">Miscellaneous</a> / <a href="./inherit.html" class="navigation-link">inherit</a></td>
  13 </tr></table><div class="header-separator"></div>
  14 <div class="section" id="inherit">
  15 <h1><a class="toc-backref" href="./miscellaneous.html#id1566">inherit</a></h1>
  16 <div class="section" id="id1163">
  17 <h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3>
  18 <pre class="literal-block">
  19 template&lt;
  20       typename T1, typename T2
  21     &gt;
  22 struct <a href="./inherit.html" class="identifier">inherit</a><tt class="literal"><span class="pre">2</span></tt>
  23 {
  24     typedef <em>unspecified</em> type;
  25 };
  26
  27 <em>...</em>
  28
  29 template&lt;
  30       typename T1, typename T2,<em>...</em> typename T<em>n</em>
  31     &gt;
  32 struct <a href="./inherit.html" class="identifier">inherit</a><em>n</em>
  33 {
  34     typedef <em>unspecified</em> type;
  35 };
  36
  37 template&lt;
  38       typename T1
  39     , typename T2
  40     <em>...</em>
  41     , typename T<em>n</em> = <em>unspecified</em>
  42     &gt;
  43 struct <a href="./inherit.html" class="identifier">inherit</a>
  44 {
  45     typedef <em>unspecified</em> type;
  46 };
  47 </pre>
  48 </div>
  49 <div class="section" id="id1164">
  50 <h3><a class="subsection-title" href="#description" name="description">Description</a></h3>
  51 <p>Returns an unspecified class type publically derived from <tt class="literal"><span class="pre">T1</span></tt>, <tt class="literal"><span class="pre">T2</span></tt>,... <tt class="literal"><span class="pre">Tn</span></tt>.
  52 Guarantees that derivation from <a class="reference internal" href="./empty-base.html">empty_base</a> is always a no-op,
  53 regardless of the position and number of <a class="reference internal" href="./empty-base.html">empty_base</a> classes in
  54 <tt class="literal"><span class="pre">T1</span></tt>, <tt class="literal"><span class="pre">T2</span></tt>,... <tt class="literal"><span class="pre">Tn</span></tt>.</p>
  55 </div>
  56 <div class="section" id="id1165">
  57 <h3><a class="subsection-title" href="#header" name="header">Header</a></h3>
  58 <pre class="literal-block">
  59 #include &lt;<a href="../../../../boost/mpl/inherit.hpp" class="header">boost/mpl/inherit.hpp</a>&gt;
  60 </pre>
  61 </div>
  62 <div class="section" id="id1166">
  63 <h3><a class="subsection-title" href="#model-of" name="model-of">Model of</a></h3>
  64 <p><a class="reference internal" href="./metafunction.html">Metafunction</a></p>
  65 </div>
  66 <div class="section" id="id1167">
  67 <h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3>
  68 <table border="1" class="docutils table">
  69 <colgroup>
  70 <col width="22%" />
  71 <col width="28%" />
  72 <col width="51%" />
  73 </colgroup>
  74 <thead valign="bottom">
  75 <tr><th class="head">Parameter</th>
  76 <th class="head">Requirement</th>
  77 <th class="head">Description</th>
  78 </tr>
  79 </thead>
  80 <tbody valign="top">
  81 <tr><td><tt class="literal"><span class="pre">T1</span></tt>, <tt class="literal"><span class="pre">T2</span></tt>,... <tt class="literal"><span class="pre">Tn</span></tt></td>
  82 <td>A class type</td>
  83 <td>Classes to derived from.</td>
  84 </tr>
  85 </tbody>
  86 </table>
  87 </div>
  88 <div class="section" id="id1168">
  89 <h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3>
  90 <p>For artibrary class types <em>t</em><sub>1</sub>,<em>t</em><sub>2</sub>,... <em>t</em><sub>n</sub>:</p>
  91 <pre class="literal-block">
  92 typedef inherit2&lt;t1,t2&gt;::type r;
  93 </pre>
  94 <table class="docutils field-list" frame="void" rules="none">
  95 <col class="field-name" />
  96 <col class="field-body" />
  97 <tbody valign="top">
  98 <tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first">A class type.</p>
  99 </td>
 100 </tr>
 101 <tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">t1</span></tt> and <tt class="literal"><span class="pre">t2</span></tt> are complete types.</p>
 102 </td>
 103 </tr>
 104 <tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first">If both <tt class="literal"><span class="pre">t1</span></tt> and <tt class="literal"><span class="pre">t2</span></tt> are identical to <tt class="literal"><span class="pre"><a href="./empty-base.html" class="identifier">empty_base</a></span></tt>, equivalent to</p>
 105 <pre class="literal-block">
 106 typedef <a href="./empty-base.html" class="identifier">empty_base</a> r;
 107 </pre>
 108 <p>otherwise, if <tt class="literal"><span class="pre">t1</span></tt> is identical to <tt class="literal"><span class="pre"><a href="./empty-base.html" class="identifier">empty_base</a></span></tt>, equivalent to</p>
 109 <pre class="literal-block">
 110 typedef t2 r;
 111 </pre>
 112 <p>otherwise, if <tt class="literal"><span class="pre">t2</span></tt> is identical to <tt class="literal"><span class="pre"><a href="./empty-base.html" class="identifier">empty_base</a></span></tt>, equivalent to</p>
 113 <pre class="literal-block">
 114 typedef t1 r;
 115 </pre>
 116 <p>otherwise equivalent to</p>
 117 <pre class="last literal-block">
 118 struct r : t1, t2 {};
 119 </pre>
 120 </td>
 121 </tr>
 122 </tbody>
 123 </table>
 124 <!-- ........................................................................... -->
 125 <pre class="literal-block">
 126 typedef <a href="./inherit.html" class="identifier">inherit</a><em>n</em>&lt;t1,t2,<em>...</em>t<em>n</em>&gt;::type r;
 127 </pre>
 128 <table class="docutils field-list" frame="void" rules="none">
 129 <col class="field-name" />
 130 <col class="field-body" />
 131 <tbody valign="top">
 132 <tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first">A class type.</p>
 133 </td>
 134 </tr>
 135 <tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><em>t</em><sub>1</sub>,<em>t</em><sub>2</sub>,... <em>t</em><sub>n</sub> are complete types.</p>
 136 </td>
 137 </tr>
 138 <tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first">Equivalent to</p>
 139 <pre class="last literal-block">
 140 struct r
 141     : <a href="./inherit.html" class="identifier">inherit</a><tt class="literal"><span class="pre">2</span></tt>&lt;
 142           <a href="./inherit.html" class="identifier">inherit</a><em>n-1</em>&lt;t1,t2,<em>...</em>t<em>n-1</em>&gt;::type
 143         , t<em>n</em>
 144         &gt;
 145 {
 146 };
 147 </pre>
 148 </td>
 149 </tr>
 150 </tbody>
 151 </table>
 152 <!-- ........................................................................... -->
 153 <pre class="literal-block">
 154 typedef <a href="./inherit.html" class="identifier">inherit</a>&lt;t1,t2,<em>...</em>t<em>n</em>&gt;::type r;
 155 </pre>
 156 <table class="docutils field-list" frame="void" rules="none">
 157 <col class="field-name" />
 158 <col class="field-body" />
 159 <tbody valign="top">
 160 <tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><em>t</em><sub>1</sub>,<em>t</em><sub>2</sub>,... <em>t</em><sub>n</sub> are complete types.</p>
 161 </td>
 162 </tr>
 163 <tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first">A class type.</p>
 164 </td>
 165 </tr>
 166 <tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first">Equivalent to</p>
 167 <pre class="last literal-block">
 168 typedef <a href="./inherit.html" class="identifier">inherit</a><em>n</em>&lt;t1,t2,<em>...</em>t<em>n</em>&gt;::type r;
 169 </pre>
 170 </td>
 171 </tr>
 172 </tbody>
 173 </table>
 174 </div>
 175 <div class="section" id="id1169">
 176 <h3><a class="subsection-title" href="#complexity" name="complexity">Complexity</a></h3>
 177 <p>Amortized constant time.</p>
 178 </div>
 179 <div class="section" id="id1170">
 180 <h3><a class="subsection-title" href="#example" name="example">Example</a></h3>
 181 <pre class="literal-block">
 182 struct udt1 { int n; };
 183 struct udt2 {};
 184
 185 typedef <a href="./inherit.html" class="identifier">inherit</a>&lt;udt1,udt2&gt;::type r1;
 186 typedef <a href="./inherit.html" class="identifier">inherit</a>&lt;<a href="./empty-base.html" class="identifier">empty_base</a>,udt1&gt;::type r2;
 187 typedef <a href="./inherit.html" class="identifier">inherit</a>&lt;<a href="./empty-base.html" class="identifier">empty_base</a>,udt1,<a href="./empty-base.html" class="identifier">empty_base</a>,<a href="./empty-base.html" class="identifier">empty_base</a>&gt;::type r3;
 188 typedef <a href="./inherit.html" class="identifier">inherit</a>&lt;udt1,<a href="./empty-base.html" class="identifier">empty_base</a>,udt2&gt;::type r4;
 189 typedef <a href="./inherit.html" class="identifier">inherit</a>&lt;<a href="./empty-base.html" class="identifier">empty_base</a>,<a href="./empty-base.html" class="identifier">empty_base</a>&gt;::type r5;
 190
 191 <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_base_and_derived&lt; udt1, r1&gt; ));
 192 <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_base_and_derived&lt; udt2, r1&gt; ));
 193 <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same&lt; r2, udt1&gt; ));
 194 <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same&lt; r3, udt1 &gt; ));
 195 <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_base_and_derived&lt; udt1, r4 &gt; ));
 196 <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_base_and_derived&lt; udt2, r4 &gt; ));
 197 <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same&lt; r5, <a href="./empty-base.html" class="identifier">empty_base</a> > ));
 198 </pre>
 199 </div>
 200 <div class="section" id="id1171">
 201 <h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3>
 202 <p><a class="reference internal" href="./metafunctions.html">Metafunctions</a>, <a class="reference internal" href="./empty-base.html">empty_base</a>, <a class="reference internal" href="./inherit-linearly.html">inherit_linearly</a>, <a class="reference internal" href="./identity.html">identity</a></p>
 203 <!-- Metafunctions/Miscellaneous//inherit_linearly |40 -->
 204 </div>
 205 </div>
 206
 207 <div class="footer-separator"></div>
 208 <table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./always.html" class="navigation-link">Prev</a>&nbsp;<a href="./inherit-linearly.html" class="navigation-link">Next</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./always.html" class="navigation-link">Back</a>&nbsp;<a href="./inherit-linearly.html" class="navigation-link">Along</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./miscellaneous.html" class="navigation-link">Up</a>&nbsp;<a href="../refmanual.html" class="navigation-link">Home</a></span><span class="navigation-group-separator">&nbsp;|&nbsp;</span><span class="navigation-group"><a href="./refmanual_toc.html" class="navigation-link">Full TOC</a></span></td>
 209 <td><div class="copyright-footer"><div class="copyright">Copyright ©  2001-2009 Aleksey Gurtovoy and David Abrahams</div>
 210 Distributed under the Boost Software License, Version 1.0. (See accompanying
 211 file LICENSE_1_0.txt or copy at <a class="reference external" href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)</div></td></tr></table></body>
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