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: quote</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="./bind.html" class="navigation-link">Prev</a> <a href="./arg.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./bind.html" class="navigation-link">Back</a> <a href="./arg.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./composition-and-argument-binding.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="./metafunctions.html" class="navigation-link">Metafunctions</a> / <a href="./composition-and-argument-binding.html" class="navigation-link">Composition and Argument Binding</a> / <a href="./quote.html" class="navigation-link">quote</a></td> 13</tr></table><div class="header-separator"></div> 14<div class="section" id="quote"> 15<h1><a class="toc-backref" href="./composition-and-argument-binding.html#id1532">quote</a></h1> 16<div class="section" id="id938"> 17<h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> 18<pre class="literal-block"> 19template< 20 template< typename P1 > class F 21 , typename Tag = <em>unspecified</em> 22 > 23struct quote1 24{ 25 // <em>unspecified</em> 26 // <em>...</em> 27}; 28 29<em>...</em> 30 31template< 32 template< typename P1,<em>...</em> typename P<em>n</em> > class F 33 , typename Tag = <em>unspecified</em> 34 > 35struct <a href="./quote.html" class="identifier">quote</a><em>n</em> 36{ 37 // <em>unspecified</em> 38 // <em>...</em> 39}; 40</pre> 41</div> 42<div class="section" id="id939"> 43<h3><a class="subsection-title" href="#description" name="description">Description</a></h3> 44<p><tt class="literal"><span class="pre"><a href="./quote.html" class="identifier">quote</a></span></tt><em>n</em> is a higher-order primitive that wraps an <em>n</em>-ary <a class="reference internal" href="./metafunction.html">Metafunction</a> to create 45a corresponding <a class="reference internal" href="./metafunction-class.html">Metafunction Class</a>.</p> 46</div> 47<div class="section" id="id940"> 48<h3><a class="subsection-title" href="#header" name="header">Header</a></h3> 49<pre class="literal-block"> 50#include <<a href="../../../../boost/mpl/quote.hpp" class="header">boost/mpl/quote.hpp</a>> 51</pre> 52</div> 53<div class="section" id="id941"> 54<h3><a class="subsection-title" href="#model-of" name="model-of">Model of</a></h3> 55<p><a class="reference internal" href="./metafunction-class.html">Metafunction Class</a></p> 56</div> 57<div class="section" id="id942"> 58<h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3> 59<table border="1" class="docutils table"> 60<colgroup> 61<col width="18%" /> 62<col width="27%" /> 63<col width="55%" /> 64</colgroup> 65<thead valign="bottom"> 66<tr><th class="head">Parameter</th> 67<th class="head">Requirement</th> 68<th class="head">Description</th> 69</tr> 70</thead> 71<tbody valign="top"> 72<tr><td><tt class="literal"><span class="pre">F</span></tt></td> 73<td><a class="reference internal" href="./metafunction.html">Metafunction</a></td> 74<td>A metafunction to wrap.</td> 75</tr> 76<tr><td><tt class="literal"><span class="pre">Tag</span></tt></td> 77<td>Any type</td> 78<td>A tag determining wrap semantics.</td> 79</tr> 80</tbody> 81</table> 82</div> 83<div class="section" id="id943"> 84<h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> 85<p>For any <em>n</em>-ary <a class="reference internal" href="./metafunction.html">Metafunction</a> <tt class="literal"><span class="pre">f</span></tt> and arbitrary type <tt class="literal"><span class="pre">tag</span></tt>:</p> 86<pre class="literal-block"> 87typedef <a href="./quote.html" class="identifier">quote</a><em>n</em><f> g; 88typedef <a href="./quote.html" class="identifier">quote</a><em>n</em><f,tag> g; 89</pre> 90<table class="docutils field-list" frame="void" rules="none"> 91<col class="field-name" /> 92<col class="field-body" /> 93<tbody valign="top"> 94<tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first"><a class="reference internal" href="./metafunction-class.html">Metafunction Class</a></p> 95</td> 96</tr> 97<tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first">Equivalent to</p> 98<pre class="literal-block"> 99struct g 100{ 101 template< typename A1,<em>...</em> typename A<em>n</em> > struct <a href="./apply.html" class="identifier">apply</a> 102 : f<A1,<em>...</em>A<em>n</em>> 103 { 104 }; 105}; 106</pre> 107<p>if <tt class="literal"><span class="pre">f<A1,...An></span></tt> has a nested type member <tt class="literal"><span class="pre">::type</span></tt>, and to</p> 108<pre class="literal-block"> 109struct g 110{ 111 template< typename A1,<em>...</em> typename A<em>n</em> > struct <a href="./apply.html" class="identifier">apply</a> 112 { 113 typedef f<A1,<em>...</em>A<em>n</em>> type; 114 }; 115}; 116</pre> 117<p class="last">otherwise.</p> 118</td> 119</tr> 120</tbody> 121</table> 122</div> 123<div class="section" id="id944"> 124<h3><a class="subsection-title" href="#example" name="example">Example</a></h3> 125<pre class="literal-block"> 126template< typename T > struct f1 127{ 128 typedef T type; 129}; 130 131template< 132 typename T1, typename T2, typename T3, typename T4, typename T5 133 > 134struct f5 135{ 136 // no 'type' member! 137}; 138 139typedef <a href="./quote.html" class="identifier">quote</a><tt class="literal"><span class="pre">1</span></tt><f1>::<a href="./apply.html" class="identifier">apply</a><int>::type t1; 140typedef <a href="./quote.html" class="identifier">quote</a><tt class="literal"><span class="pre">5</span></tt><f5>::<a href="./apply.html" class="identifier">apply</a><char,short,int,long,float>::type t5; 141 142<a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< t1, int > )); 143<a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< t5, f5<char,short,int,long,float> > )); 144</pre> 145</div> 146<div class="section" id="id945"> 147<h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> 148<p><a class="reference internal" href="./composition-and-argument-binding.html">Composition and Argument Binding</a>, <a class="reference internal" href="./invocation.html">invocation</a>, <a class="reference internal" href="./bind.html">bind</a>, <a class="reference internal" href="./lambda.html">lambda</a>, <a class="reference internal" href="./protect.html">protect</a>, <a class="reference internal" href="./apply.html">apply</a></p> 149<!-- Metafunctions/Composition and Argument Binding//arg |50 --> 150</div> 151</div> 152 153<div class="footer-separator"></div> 154<table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./bind.html" class="navigation-link">Prev</a> <a href="./arg.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./bind.html" class="navigation-link">Back</a> <a href="./arg.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./composition-and-argument-binding.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> 155<td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div> 156Distributed under the Boost Software License, Version 1.0. (See accompanying 157file 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> 158</html> 159