libs/contract/doc/html/boost/contract/public_f_idm45123869756752.html

   1 <html>
   2 <head>
   3 <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
   4 <title>Function template public_function</title>
   5 <link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css">
   6 <meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
   7 <link rel="home" href="../../index.html" title="Chapter&#160;1.&#160;Boost.Contract 1.0.0">
   8 <link rel="up" href="../../reference.html#header.boost.contract.public_function_hpp" title="Header &lt;boost/contract/public_function.hpp&gt;">
   9 <link rel="prev" href="../../BOOST_CONTRACT_OVERRIDES.html" title="Macro BOOST_CONTRACT_OVERRIDES">
  10 <link rel="next" href="public_f_idm45123869746336.html" title="Function template public_function">
  11 </head>
  12 <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
  13 <table cellpadding="2" width="100%"><tr>
  14 <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td>
  15 <td align="center"><a href="../../../../../../index.html">Home</a></td>
  16 <td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td>
  17 <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td>
  18 <td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td>
  19 <td align="center"><a href="../../../../../../more/index.htm">More</a></td>
  20 </tr></table>
  21 <hr>
  22 <div class="spirit-nav">
  23 <a accesskey="p" href="../../BOOST_CONTRACT_OVERRIDES.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../reference.html#header.boost.contract.public_function_hpp"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="public_f_idm45123869746336.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
  24 </div>
  25 <div class="refentry">
  26 <a name="boost.contract.public_f_idm45123869756752"></a><div class="titlepage"></div>
  27 <div class="refnamediv">
  28 <h2><span class="refentrytitle">Function template public_function</span></h2>
  29 <p>boost::contract::public_function &#8212; Program contracts for static public functions. </p>
  30 </div>
  31 <h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2>
  32 <div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../reference.html#header.boost.contract.public_function_hpp" title="Header &lt;boost/contract/public_function.hpp&gt;">boost/contract/public_function.hpp</a>&gt;
  33
  34 </span>
  35 <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Class<span class="special">&gt;</span>
  36   <a class="link" href="specify__idm45123870039968.html" title="Class template specify_precondition_old_postcondition_except">specify_precondition_old_postcondition_except</a> <span class="identifier">public_function</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></div>
  37 <div class="refsect1">
  38 <a name="idm45751727417328"></a><h2>Description</h2>
  39 <p>This is used to specify preconditions, postconditions, exception guarantees, old value copies at body, and check static class invariants for static public functions:</p>
  40 <pre class="programlisting"><span class="keyword">class</span> <span class="identifier">u</span> <span class="special">{</span>
  41     <span class="keyword">friend</span> <span class="keyword">class</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">contract</span><span class="special">::</span><span class="identifier">access</span><span class="special">;</span>
  42
  43     <span class="keyword">static</span> <span class="keyword">void</span> <span class="identifier">static_invariant</span><span class="special">(</span><span class="special">)</span> <span class="special">{</span> <span class="comment">// Optional (as for non-static).</span>
  44         <span class="identifier">BOOST_CONTRACT_ASSERT</span><span class="special">(</span><span class="special">...</span><span class="special">)</span><span class="special">;</span>
  45         <span class="special">...</span>
  46     <span class="special">}</span>
  47
  48 <span class="keyword">public</span><span class="special">:</span>
  49     <span class="keyword">static</span> <span class="keyword">void</span> <span class="identifier">f</span><span class="special">(</span><span class="special">...</span><span class="special">)</span> <span class="special">{</span>
  50         <span class="identifier">boost</span><span class="special">::</span><span class="identifier">contract</span><span class="special">::</span><span class="identifier">old_ptr</span><span class="special">&lt;</span><span class="identifier">old_type</span><span class="special">&gt;</span> <span class="identifier">old_var</span><span class="special">;</span>
  51         <span class="identifier">boost</span><span class="special">::</span><span class="identifier">contract</span><span class="special">::</span><span class="identifier">check</span> <span class="identifier">c</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">contract</span><span class="special">::</span><span class="identifier">public_function</span><span class="special">&lt;</span><span class="identifier">u</span><span class="special">&gt;</span><span class="special">(</span><span class="special">)</span>
  52             <span class="special">.</span><span class="identifier">precondition</span><span class="special">(</span><span class="special">[</span><span class="special">&amp;</span><span class="special">]</span> <span class="special">{</span> <span class="comment">// Optional.</span>
  53                 <span class="identifier">BOOST_CONTRACT_ASSERT</span><span class="special">(</span><span class="special">...</span><span class="special">)</span><span class="special">;</span>
  54                 <span class="special">...</span>
  55             <span class="special">}</span><span class="special">)</span>
  56             <span class="special">.</span><span class="identifier">old</span><span class="special">(</span><span class="special">[</span><span class="special">&amp;</span><span class="special">]</span> <span class="special">{</span> <span class="comment">// Optional.</span>
  57                 <span class="identifier">old_var</span> <span class="special">=</span> <span class="identifier">BOOST_CONTRACT_OLDOF</span><span class="special">(</span><span class="identifier">old_expr</span><span class="special">)</span><span class="special">;</span>
  58                 <span class="special">...</span>
  59             <span class="special">}</span><span class="special">)</span>
  60             <span class="special">.</span><span class="identifier">postcondition</span><span class="special">(</span><span class="special">[</span><span class="special">&amp;</span><span class="special">]</span> <span class="special">{</span> <span class="comment">// Optional.</span>
  61                 <span class="identifier">BOOST_CONTRACT_ASSERT</span><span class="special">(</span><span class="special">...</span><span class="special">)</span><span class="special">;</span>
  62                 <span class="special">...</span>
  63             <span class="special">}</span><span class="special">)</span>
  64             <span class="special">.</span><span class="identifier">except</span><span class="special">(</span><span class="special">[</span><span class="special">&amp;</span><span class="special">]</span> <span class="special">{</span> <span class="comment">// Optional.</span>
  65                 <span class="identifier">BOOST_CONTRACT_ASSERT</span><span class="special">(</span><span class="special">...</span><span class="special">)</span><span class="special">;</span>
  66                 <span class="special">...</span>
  67             <span class="special">}</span><span class="special">)</span>
  68         <span class="special">;</span>
  69
  70         <span class="special">...</span> <span class="comment">// Function body.</span>
  71     <span class="special">}</span>
  72
  73     <span class="special">...</span>
  74 <span class="special">}</span><span class="special">;</span>
  75 </pre>
  76 <p>For optimization, this can be omitted for static public functions that do not have preconditions, postconditions and exception guarantees, within classes that have no static invariants.</p>
  77 <p><span class="bold"><strong>See Also:</strong></span></p>
  78 <p> <a class="link" href="../../boost_contract/tutorial.html#boost_contract.tutorial.static_public_functions" title="Static Public Functions"> Static Public Functions</a></p>
  79 <p>
  80 </p>
  81 <p>
  82
  83
  84 </p>
  85 <div class="variablelist"><table border="0" class="variablelist compact">
  86 <colgroup>
  87 <col align="left" valign="top">
  88 <col>
  89 </colgroup>
  90 <tbody>
  91 <tr>
  92 <td><p><span class="term">Template Parameters:</span></p></td>
  93 <td><div class="variablelist"><table border="0" class="variablelist compact">
  94 <colgroup>
  95 <col align="left" valign="top">
  96 <col>
  97 </colgroup>
  98 <tbody><tr>
  99 <td><p><span class="term"><code class="computeroutput">Class</code></span></p></td>
 100 <td><p>The type of the class containing the static public function declaring the contract. This template parameter must be explicitly specified for static public functions (because they have no object <code class="computeroutput">this</code> so there is no function argument from which this type template parameter can be deduced by this library).</p></td>
 101 </tr></tbody>
 102 </table></div></td>
 103 </tr>
 104 <tr>
 105 <td><p><span class="term">Returns:</span></p></td>
 106 <td><p>The result of this function must be explicitly assigned to a variable of type <code class="computeroutput"><a class="link" href="check.html" title="Class check">boost::contract::check</a></code> declared locally just before the code of the static function body (otherwise this library will generate a run-time error, see <code class="computeroutput"><a class="link" href="../../BOOST_CO_idm45123870548928.html" title="Macro BOOST_CONTRACT_ON_MISSING_CHECK_DECL">BOOST_CONTRACT_ON_MISSING_CHECK_DECL</a></code>). </p></td>
 107 </tr>
 108 </tbody>
 109 </table></div>
 110 </div>
 111 </div>
 112 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 113 <td align="left"></td>
 114 <td align="right"><div class="copyright-footer">Copyright &#169; 2008-2018 Lorenzo Caminiti<p>
 115         Distributed under the Boost Software License, Version 1.0 (see accompanying
 116         file LICENSE_1_0.txt or a copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
 117       </p>
 118 </div></td>
 119 </tr></table>
 120 <hr>
 121 <div class="spirit-nav">
 122 <a accesskey="p" href="../../BOOST_CONTRACT_OVERRIDES.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../reference.html#header.boost.contract.public_function_hpp"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="public_f_idm45123869746336.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a>
 123 </div>
 124 </body>
 125 </html>