1<?xml version="1.0" encoding="utf-8" ?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> 4<head> 5<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 6<meta name="generator" content="Docutils 0.7: http://docutils.sourceforge.net/" /> 7<title>The MPL Reference Manual: bool_</title> 8<link rel="stylesheet" href="../style.css" type="text/css" /> 9</head> 10<body class="docframe refmanual"> 11<table class="header"><tr class="header"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./numeric.html" class="navigation-link">Prev</a> <a href="./int.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group">Back <a href="./int.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./numeric.html" class="navigation-link">Up</a> <a href="../refmanual.html" class="navigation-link">Home</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./refmanual_toc.html" class="navigation-link">Full TOC</a></span></td> 12<td class="header-group page-location"><a href="../refmanual.html" class="navigation-link">Front Page</a> / <a href="./data-types.html" class="navigation-link">Data Types</a> / <a href="./numeric.html" class="navigation-link">Numeric</a> / <a href="./bool.html" class="navigation-link">bool_</a></td> 13</tr></table><div class="header-separator"></div> 14<div class="section" id="bool"> 15<h1><a class="toc-backref" href="./numeric.html#id1576">bool_</a></h1> 16<div class="section" id="id1222"> 17<h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> 18<pre class="literal-block"> 19template< 20 bool C 21 > 22struct <a href="./bool.html" class="identifier">bool_</a> 23{ 24 // <em>unspecified</em> 25 // ... 26}; 27 28typedef <a href="./bool.html" class="identifier">bool_</a><true> <a href="./bool.html" class="identifier">true_</a>; 29typedef <a href="./bool.html" class="identifier">bool_</a><false> <a href="./bool.html" class="identifier">false_</a>; 30</pre> 31</div> 32<div class="section" id="id1223"> 33<h3><a class="subsection-title" href="#description" name="description">Description</a></h3> 34<p>A boolean <a class="reference internal" href="./integral-constant.html">Integral Constant</a> wrapper.</p> 35</div> 36<div class="section" id="id1224"> 37<h3><a class="subsection-title" href="#header" name="header">Header</a></h3> 38<pre class="literal-block"> 39#include <<a href="../../../../boost/mpl/bool.hpp" class="header">boost/mpl/bool.hpp</a>> 40</pre> 41</div> 42<div class="section" id="id1225"> 43<h3><a class="subsection-title" href="#model-of" name="model-of">Model of</a></h3> 44<p><a class="reference internal" href="./integral-constant.html">Integral Constant</a></p> 45</div> 46<div class="section" id="id1226"> 47<h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3> 48<table border="1" class="docutils table"> 49<colgroup> 50<col width="21%" /> 51<col width="42%" /> 52<col width="37%" /> 53</colgroup> 54<thead valign="bottom"> 55<tr><th class="head">Parameter</th> 56<th class="head">Requirement</th> 57<th class="head">Description</th> 58</tr> 59</thead> 60<tbody valign="top"> 61<tr><td><tt class="literal"><span class="pre">C</span></tt></td> 62<td>A boolean integral constant</td> 63<td>A value to wrap.</td> 64</tr> 65</tbody> 66</table> 67</div> 68<div class="section" id="id1227"> 69<h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> 70<p>The semantics of an expression are defined only 71where they differ from, or are not defined in <a class="reference internal" href="./integral-constant.html">Integral Constant</a>.</p> 72<p>For arbitrary integral constant <tt class="literal"><span class="pre">c</span></tt>:</p> 73<table border="1" class="docutils table"> 74<colgroup> 75<col width="24%" /> 76<col width="76%" /> 77</colgroup> 78<thead valign="bottom"> 79<tr><th class="head">Expression</th> 80<th class="head">Semantics</th> 81</tr> 82</thead> 83<tbody valign="top"> 84<tr><td><tt class="literal"><span class="pre"><a href="./bool.html" class="identifier">bool_</a><c></span></tt></td> 85<td>An <a class="reference internal" href="./integral-constant.html">Integral Constant</a> <tt class="literal"><span class="pre">x</span></tt> such that <tt class="literal"><span class="pre">x::value</span> <span class="pre">==</span> <span class="pre">c</span></tt> 86and <tt class="literal"><span class="pre">x::<a href="./value-type.html" class="identifier">value_type</a></span></tt> is identical to <tt class="literal"><span class="pre">bool</span></tt>.</td> 87</tr> 88</tbody> 89</table> 90</div> 91<div class="section" id="id1228"> 92<h3><a class="subsection-title" href="#example" name="example">Example</a></h3> 93<pre class="literal-block"> 94<a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< <a href="./bool.html" class="identifier">bool_</a><true>::<a href="./value-type.html" class="identifier">value_type</a>, bool > )); 95<a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< <a href="./bool.html" class="identifier">bool_</a><true>, <a href="./bool.html" class="identifier">true_</a> > )); } 96<a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< <a href="./bool.html" class="identifier">bool_</a><true>::type, <a href="./bool.html" class="identifier">bool_</a><true> > )); 97<a href="./assert-relation.html" class="identifier">BOOST_MPL_ASSERT_RELATION</a>( <a href="./bool.html" class="identifier">bool_</a><true>::value, ==, true ); 98assert( <a href="./bool.html" class="identifier">bool_</a><true>() == true ); 99</pre> 100</div> 101<div class="section" id="id1229"> 102<h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> 103<p><a class="reference internal" href="./data-types.html">Data Types</a>, <a class="reference internal" href="./integral-constant.html">Integral Constant</a>, <a class="reference internal" href="./int.html">int_</a>, <a class="reference internal" href="./long.html">long_</a>, <a class="reference internal" href="./integral-c.html">integral_c</a></p> 104<!-- Data Types/Numeric//int_ |20 --> 105</div> 106</div> 107 108<div class="footer-separator"></div> 109<table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./numeric.html" class="navigation-link">Prev</a> <a href="./int.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group">Back <a href="./int.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./numeric.html" class="navigation-link">Up</a> <a href="../refmanual.html" class="navigation-link">Home</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./refmanual_toc.html" class="navigation-link">Full TOC</a></span></td> 110<td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div> 111Distributed under the Boost Software License, Version 1.0. (See accompanying 112file 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> 113</html> 114