1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>Macro BOOST_INTRUSIVE_OPTION_CONSTANT</title> 6<link rel="stylesheet" href="../../doc/src/boostbook.css" type="text/css"> 7<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 8<link rel="home" href="index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> 9<link rel="up" href="intrusive/reference.html#header.boost.intrusive.pack_options_hpp" title="Header <boost/intrusive/pack_options.hpp>"> 10<link rel="prev" href="BOOST_IN_idm45020921475488.html" title="Macro BOOST_INTRUSIVE_OPTION_TYPE"> 11<link rel="next" href="boost/intrusive/get_pare_idm45020921461200.html" title="Function template get_parent_from_member"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../boost.png"></td> 16<td align="center"><a href="../../index.html">Home</a></td> 17<td align="center"><a href="../../libs/libraries.htm">Libraries</a></td> 18<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 19<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 20<td align="center"><a href="../../more/index.htm">More</a></td> 21</tr></table> 22<hr> 23<div class="spirit-nav"> 24<a accesskey="p" href="BOOST_IN_idm45020921475488.html"><img src="../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="intrusive/reference.html#header.boost.intrusive.pack_options_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/intrusive/get_pare_idm45020921461200.html"><img src="../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="refentry"> 27<a name="BOOST_IN_idm45020921469264"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Macro BOOST_INTRUSIVE_OPTION_CONSTANT</span></h2> 30<p>BOOST_INTRUSIVE_OPTION_CONSTANT</p> 31</div> 32<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 33<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="intrusive/reference.html#header.boost.intrusive.pack_options_hpp" title="Header <boost/intrusive/pack_options.hpp>">boost/intrusive/pack_options.hpp</a>> 34 35</span>BOOST_INTRUSIVE_OPTION_CONSTANT(OPTION_NAME, TYPE, VALUE, CONSTANT_NAME)</pre></div> 36<div class="refsect1"> 37<a name="id-1.3.20.42.22.6.4"></a><h2>Description</h2> 38<p>Defines an option class of name OPTION_NAME that can be used to specify a constant of type TYPE with value VALUE...</p> 39<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">OPTION_NAME</span><span class="special"><</span><span class="identifier">TYPE</span> <span class="identifier">VALUE</span><span class="special">></span> 40<span class="special">{</span> <span class="identifier">unspecified_content</span> <span class="special">}</span><span class="special">;</span> 41</pre> 42<p>...that after being combined with <code class="computeroutput"><a class="link" href="boost/intrusive/pack_options.html" title="Struct template pack_options">boost::intrusive::pack_options</a></code>, will contain a CONSTANT_NAME static constant of value VALUE. Example:</p> 43<pre class="programlisting"><span class="comment">//[includes and namespaces omitted for brevity]</span> 44 45<span class="comment">//This macro will create the following class:</span> 46<span class="comment">// template<bool Enabled></span> 47<span class="comment">// struct incremental</span> 48<span class="comment">// { unspecified_content };</span> 49<span class="identifier">BOOST_INTRUSIVE_OPTION_CONSTANT</span><span class="special">(</span><span class="identifier">incremental</span><span class="special">,</span> <span class="keyword">bool</span><span class="special">,</span> <span class="identifier">Enabled</span><span class="special">,</span> <span class="identifier">is_incremental</span><span class="special">)</span> 50 51<span class="keyword">struct</span> <span class="identifier">empty_default</span><span class="special">{</span><span class="special">}</span><span class="special">;</span> 52 53<span class="keyword">const</span> <span class="keyword">bool</span> <span class="identifier">is_incremental</span> <span class="special">=</span> <span class="identifier">pack_options</span><span class="special"><</span> <span class="identifier">empty_default</span><span class="special">,</span> <span class="identifier">incremental</span><span class="special"><</span><span class="keyword">true</span><span class="special">></span> <span class="special">></span><span class="special">::</span><span class="identifier">type</span><span class="special">::</span><span class="identifier">is_incremental</span><span class="special">;</span> 54 55<span class="identifier">BOOST_STATIC_ASSERT</span><span class="special">(</span><span class="special">(</span> <span class="identifier">is_incremental</span> <span class="special">==</span> <span class="keyword">true</span> <span class="special">)</span><span class="special">)</span><span class="special">;</span> 56</pre> 57<p> </p> 58</div> 59</div> 60<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 61<td align="left"></td> 62<td align="right"><div class="copyright-footer">Copyright © 2005 Olaf Krzikalla<br>Copyright © 2006-2015 Ion Gaztanaga<p> 63 Distributed under the Boost Software License, Version 1.0. (See accompanying 64 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 65 </p> 66</div></td> 67</tr></table> 68<hr> 69<div class="spirit-nav"> 70<a accesskey="p" href="BOOST_IN_idm45020921475488.html"><img src="../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="intrusive/reference.html#header.boost.intrusive.pack_options_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/intrusive/get_pare_idm45020921461200.html"><img src="../../doc/src/images/next.png" alt="Next"></a> 71</div> 72</body> 73</html> 74
