1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> 4<title>Macro BOOST_TTI_TRAIT_HAS_MEMBER_DATA</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. The Type Traits Introspection Library"> 8<link rel="up" href="header/boost/tti/has_member_data_hpp.html" title="Header <boost/tti/has_member_data.hpp>"> 9<link rel="prev" href="header/boost/tti/has_member_data_hpp.html" title="Header <boost/tti/has_member_data.hpp>"> 10<link rel="next" href="BOOST_TTI_HAS_MEMBER_DATA.html" title="Macro BOOST_TTI_HAS_MEMBER_DATA"> 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="header/boost/tti/has_member_data_hpp.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="header/boost/tti/has_member_data_hpp.html"><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_TTI_HAS_MEMBER_DATA.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="refentry"> 26<a name="BOOST_TT_idm46187194146272"></a><div class="titlepage"></div> 27<div class="refnamediv"> 28<h2><span class="refentrytitle">Macro BOOST_TTI_TRAIT_HAS_MEMBER_DATA</span></h2> 29<p>BOOST_TTI_TRAIT_HAS_MEMBER_DATA — Expands to a metafunction which tests whether a member data with a particular name and type exists. </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: <<a class="link" href="header/boost/tti/has_member_data_hpp.html" title="Header <boost/tti/has_member_data.hpp>">boost/tti/has_member_data.hpp</a>> 33 34</span>BOOST_TTI_TRAIT_HAS_MEMBER_DATA(trait, name)</pre></div> 35<div class="refsect1"> 36<a name="idm45456560503728"></a><h2>Description</h2> 37<p>trait = the name of the metafunction.</p> 38<p>name = the name of the inner member to introspect.</p> 39<p>generates a metafunction called "trait" where 'trait' is the macro parameter. template<class BOOST_TTI_TP_ET,class BOOST_TTI_TP_TYPE> 40 struct trait 41 { 42 static const value = unspecified; 43 typedef mpl::bool_<true-or-false> type; 44 }; 45 46 The metafunction types and return: 47 48 BOOST_TTI_TP_ET = the enclosing type in which to look for our 'name' 49 OR 50 The type of the member data in the form of a pointer 51 to member data. 52 53 BOOST_TTI_TP_TYPE = (optional) The type of the member data if the first 54 parameter is the enclosing type. 55 56 returns = 'value' is true if the 'name' exists, with the correct data type, 57 otherwise 'value' is false. 58 </p> 59</div> 60</div> 61<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 62<td align="left"></td> 63<td align="right"><div class="copyright-footer">Copyright © 2011-2013 Tropic Software 64 East Inc<p> 65 Distributed under the Boost Software License, Version 1.0. (See accompanying 66 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>) 67 </p> 68</div></td> 69</tr></table> 70<hr> 71<div class="spirit-nav"> 72<a accesskey="p" href="header/boost/tti/has_member_data_hpp.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="header/boost/tti/has_member_data_hpp.html"><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_TTI_HAS_MEMBER_DATA.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 73</div> 74</body> 75</html> 76
