• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1<html>
2<head>
3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
4<title>Macro BOOST_CONTRACT_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 1. Boost.Contract 1.0.0">
8<link rel="up" href="reference.html#header.boost.contract_macro_hpp" title="Header &lt;boost/contract_macro.hpp&gt;">
9<link rel="prev" href="BOOST_CO_idm46268584347456.html" title="Macro BOOST_CONTRACT_STATIC_PUBLIC_FUNCTION">
10<link rel="next" href="BOOST_CO_idm46268584298528.html" title="Macro BOOST_CONTRACT_PUBLIC_FUNCTION_OVERRIDE">
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_CO_idm46268584347456.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="reference.html#header.boost.contract_macro_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="BOOST_CO_idm46268584298528.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
24</div>
25<div class="refentry">
26<a name="BOOST_CO_idm46268584330448"></a><div class="titlepage"></div>
27<div class="refnamediv">
28<h2><span class="refentrytitle">Macro BOOST_CONTRACT_PUBLIC_FUNCTION</span></h2>
29<p>BOOST_CONTRACT_PUBLIC_FUNCTION — Program contracts that can be completely disabled at compile-time for non-static public functions that do not override. </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_macro_hpp" title="Header &lt;boost/contract_macro.hpp&gt;">boost/contract_macro.hpp</a>&gt;
33
34</span>BOOST_CONTRACT_PUBLIC_FUNCTION(...)</pre></div>
35<div class="refsect1">
36<a name="idm45988674922176"></a><h2>Description</h2>
37<p>This is used together with <code class="computeroutput"><a class="link" href="BOOST_CO_idm46268584560672.html" title="Macro BOOST_CONTRACT_PRECONDITION">BOOST_CONTRACT_PRECONDITION</a></code>,  <code class="computeroutput"><a class="link" href="BOOST_CO_idm46268584548992.html" title="Macro BOOST_CONTRACT_POSTCONDITION">BOOST_CONTRACT_POSTCONDITION</a></code>, <code class="computeroutput"><a class="link" href="BOOST_CONTRACT_EXCEPT.html" title="Macro BOOST_CONTRACT_EXCEPT">BOOST_CONTRACT_EXCEPT</a></code>, and <code class="computeroutput"><a class="link" href="BOOST_CONTRACT_OLD.html" title="Macro BOOST_CONTRACT_OLD">BOOST_CONTRACT_OLD</a></code> to specify preconditions, postconditions, exception guarantees, and old value copies at body that can be completely disabled at compile-time for non-static public functions (virtual or not, void or not) that do not override:</p>
38<pre class="programlisting"><span class="keyword">class</span> <span class="identifier">u</span> <span class="special">{</span>
39    <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>
40
41    <span class="identifier">BOOST_CONTRACT_INVARIANT</span><span class="special">(</span><span class="special">{</span> <span class="comment">// Optional (as for static and volatile).</span>
42        <span class="identifier">BOOST_CONTRACT_ASSERT</span><span class="special">(</span><span class="special">...</span><span class="special">)</span><span class="special">;</span>
43        <span class="special">...</span>
44    <span class="special">}</span><span class="special">)</span>
45
46<span class="keyword">public</span><span class="special">:</span>
47    <span class="comment">// Non-virtual (same if void).</span>
48    <span class="identifier">t</span> <span class="identifier">f</span><span class="special">(</span><span class="special">...</span><span class="special">)</span> <span class="special">{</span>
49        <span class="identifier">t</span> <span class="identifier">result</span><span class="special">;</span>
50        <span class="identifier">BOOST_CONTRACT_OLD_PTR</span><span class="special">(</span><span class="identifier">old_type</span><span class="special">)</span><span class="special">(</span><span class="identifier">old_var</span><span class="special">)</span><span class="special">;</span>
51        <span class="identifier">BOOST_CONTRACT_PUBLIC_FUNCTION</span><span class="special">(</span><span class="keyword">this</span><span class="special">)</span>
52            <span class="identifier">BOOST_CONTRACT_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="identifier">BOOST_CONTRACT_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="identifier">BOOST_CONTRACT_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="identifier">BOOST_CONTRACT_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> <span class="comment">// Trailing `;` is required.</span>
69
70        <span class="special">...</span> <span class="comment">// Function body (use `return result = return_expr`).</span>
71    <span class="special">}</span>
72
73    <span class="comment">// Virtual and void.</span>
74    <span class="keyword">virtual</span> <span class="keyword">void</span> <span class="identifier">g</span><span class="special">(</span><span class="special">...</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">virtual_</span><span class="special">*</span> <span class="identifier">v</span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span> <span class="special">{</span>
75        <span class="identifier">BOOST_CONTRACT_OLD_PTR</span><span class="special">(</span><span class="identifier">old_type</span><span class="special">)</span><span class="special">(</span><span class="identifier">old_var</span><span class="special">)</span><span class="special">;</span>
76        <span class="identifier">BOOST_CONTRACT_PUBLIC_FUNCTION</span><span class="special">(</span><span class="identifier">v</span><span class="special">,</span> <span class="keyword">this</span><span class="special">)</span>
77            <span class="special">...</span>
78            <span class="identifier">BOOST_CONTRACT_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>
79                <span class="identifier">old_var</span> <span class="special">=</span> <span class="identifier">BOOST_CONTRACT_OLDOF</span><span class="special">(</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">old_expr</span><span class="special">)</span><span class="special">;</span>
80                <span class="special">...</span>
81            <span class="special">}</span><span class="special">)</span>
82            <span class="special">...</span>
83        <span class="special">;</span> <span class="comment">// Trailing `;` is required.</span>
84
85        <span class="special">...</span> <span class="comment">// Function body.</span>
86    <span class="special">}</span>
87
88    <span class="comment">// Virtual and non-void.</span>
89    <span class="keyword">virtual</span> <span class="identifier">t</span> <span class="identifier">h</span><span class="special">(</span><span class="special">...</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">virtual_</span><span class="special">*</span> <span class="identifier">v</span> <span class="special">=</span> <span class="number">0</span><span class="special">)</span> <span class="special">{</span>
90        <span class="identifier">t</span> <span class="identifier">result</span><span class="special">;</span>
91        <span class="identifier">BOOST_CONTRACT_OLD_PTR</span><span class="special">(</span><span class="identifier">old_type</span><span class="special">)</span><span class="special">(</span><span class="identifier">old_var</span><span class="special">)</span><span class="special">;</span>
92        <span class="identifier">BOOST_CONTRACT_PUBLIC_FUNCTION</span><span class="special">(</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">result</span><span class="special">,</span> <span class="keyword">this</span><span class="special">)</span>
93            <span class="special">...</span>
94            <span class="identifier">BOOST_CONTRACT_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>
95                <span class="identifier">old_var</span> <span class="special">=</span> <span class="identifier">BOOST_CONTRACT_OLDOF</span><span class="special">(</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">old_expr</span><span class="special">)</span><span class="special">;</span>
96                <span class="special">...</span>
97            <span class="special">}</span><span class="special">)</span>
98            <span class="identifier">BOOST_CONTRACT_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="identifier">t</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">result</span><span class="special">)</span> <span class="special">{</span> <span class="comment">// Optional</span>
99                <span class="identifier">BOOST_CONTRACT_ASSERT</span><span class="special">(</span><span class="special">...</span><span class="special">)</span><span class="special">;</span>
100                <span class="special">...</span>
101            <span class="special">}</span><span class="special">)</span>
102            <span class="special">...</span>
103        <span class="special">;</span> <span class="comment">// Trailing `;` is required.</span>
104
105        <span class="special">...</span> <span class="comment">// Function body (use `return result = return_expr`).</span>
106    <span class="special">}</span>
107
108    <span class="special">...</span>
109<span class="special">}</span><span class="special">;</span>
110</pre>
111<p>For optimization, this can be omitted for non-virtual public functions that do not have preconditions, postconditions and exception guarantees, within classes that have no invariants. Virtual public functions should always use  <code class="computeroutput"><a class="link" href="BOOST_CO_idm46268584330448.html" title="Macro BOOST_CONTRACT_PUBLIC_FUNCTION">BOOST_CONTRACT_PUBLIC_FUNCTION</a></code> otherwise this library will not be able to correctly use them for subcontracting.</p>
112<p>This is an overloaded variadic macro and it can be used in the following different ways (note that no code is generated when  <code class="computeroutput"><a class="link" href="BOOST_CO_idm46268585398736.html" title="Macro BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS">BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS</a></code> is defined).</p>
113<p>1. <code class="computeroutput">BOOST_CONTRACT_PUBLIC_FUNCTION(obj)</code> expands to code equivalent to the following (for non-virtual public functions that are not static and do not override, returning void or not):</p>
114<pre class="programlisting"><span class="preprocessor">#ifndef</span> <span class="identifier">BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS</span>
115    <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">internal_var</span> <span class="special">=</span>
116            <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">(</span><span class="identifier">obj</span><span class="special">)</span>
117<span class="preprocessor">#endif</span>
118</pre>
119<p>2. <code class="computeroutput">BOOST_CONTRACT_PUBLIC_FUNCTION(v, obj)</code> expands to code equivalent to the following (for virtual public functions that do not override, returning void):</p>
120<pre class="programlisting"><span class="preprocessor">#ifndef</span> <span class="identifier">BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS</span>
121    <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">internal_var</span> <span class="special">=</span>
122            <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">(</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">obj</span><span class="special">)</span>
123<span class="preprocessor">#endif</span>
124</pre>
125<p>3. <code class="computeroutput">BOOST_CONTRACT_PUBLIC_FUNCTION(v, r, obj)</code> expands to code equivalent to the following (for virtual public functions that do not override, not returning void):</p>
126<pre class="programlisting"><span class="preprocessor">#ifndef</span> <span class="identifier">BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS</span>
127    <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">internal_var</span> <span class="special">=</span>
128            <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">(</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">r</span><span class="special">,</span> <span class="identifier">obj</span><span class="special">)</span>
129<span class="preprocessor">#endif</span>
130</pre>
131<p>Where (these are all variadic macro parameters so they can contain commas not protected by round parenthesis):</p>
132<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
133<li class="listitem"><p><code class="computeroutput"><span class="bold"><strong>v</strong></span></code> is the extra parameter of type  <code class="computeroutput"><a class="link" href="boost/contract/virtual_.html" title="Class virtual_">boost::contract::virtual_</a></code><code class="computeroutput">*</code> and default value <code class="computeroutput">0</code> from the enclosing virtual public function declaring the contract. </p></li>
134<li class="listitem"><p><code class="computeroutput"><span class="bold"><strong>r</strong></span></code> is a reference to the return value of the enclosing virtual public function declaring the contract. This is usually a local variable declared by the enclosing virtual public function just before the contract, but programmers must set it to the actual value being returned by the function at each <code class="computeroutput">return</code> statement. </p></li>
135<li class="listitem"><p><code class="computeroutput"><span class="bold"><strong>obj</strong></span></code> is the object <code class="computeroutput">this</code> from the scope of the enclosing public function declaring the contract. This object might be mutable, <code class="computeroutput">const</code>, <code class="computeroutput">volatile</code>, or <code class="computeroutput">const volatile</code> depending on the cv-qualifier of the enclosing function (volatile public functions will check volatile class invariants, see <a class="link" href="boost_contract/extras.html#boost_contract.extras.volatile_public_functions" title="Volatile Public Functions">
136        Volatile Public Functions</a>). </p></li>
137<li class="listitem"><p><code class="computeroutput"><span class="bold"><strong>internal_var</strong></span></code> is a variable name internally generated by this library (this name is unique but only on different line numbers so this macro cannot be expanded multiple times on the same line).</p></li>
138</ul></div>
139<p>
140</p>
141<p><span class="bold"><strong>See Also:</strong></span></p>
142<p> <a class="link" href="boost_contract/extras.html#boost_contract.extras.disable_contract_compilation__macro_interface_" title="Disable Contract Compilation (Macro Interface)">
143        Disable Contract Compilation</a>,  <a class="link" href="boost_contract/tutorial.html#boost_contract.tutorial.public_functions" title="Public Functions"> Public Functions</a>,  <a class="link" href="boost_contract/tutorial.html#boost_contract.tutorial.virtual_public_functions" title="Virtual Public Functions">
144        Virtual Public Functions</a> </p>
145<p>
146</p>
147<p>
148</p>
149</div>
150</div>
151<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
152<td align="left"></td>
153<td align="right"><div class="copyright-footer">Copyright © 2008-2019 Lorenzo Caminiti<p>
154        Distributed under the Boost Software License, Version 1.0 (see accompanying
155        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>)
156      </p>
157</div></td>
158</tr></table>
159<hr>
160<div class="spirit-nav">
161<a accesskey="p" href="BOOST_CO_idm46268584347456.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="reference.html#header.boost.contract_macro_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="BOOST_CO_idm46268584298528.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a>
162</div>
163</body>
164</html>
165