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: apply</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="./invocation.html" class="navigation-link">Prev</a> <a href="./apply-wrap.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group">Back <a href="./apply-wrap.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./invocation.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="./invocation.html" class="navigation-link">Invocation</a> / <a href="./apply.html" class="navigation-link">apply</a></td> 13</tr></table><div class="header-separator"></div> 14<div class="section" id="apply"> 15<h1><a class="toc-backref" href="./invocation.html#id1525">apply</a></h1> 16<div class="section" id="id887"> 17<h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> 18<pre class="literal-block"> 19template< 20 typename F 21 > 22struct apply0 23{ 24 typedef <em>unspecified</em> type; 25}; 26 27template< 28 typename F, typename A1 29 > 30struct apply1 31{ 32 typedef <em>unspecified</em> type; 33}; 34 35<em>...</em> 36 37template< 38 typename F, typename A1,<em>...</em> typename An 39 > 40struct <a href="./apply.html" class="identifier">apply</a><em>n</em> 41{ 42 typedef <em>unspecified</em> type; 43}; 44 45template< 46 typename F 47 , typename A1 = <em>unspecified</em> 48 <em>...</em> 49 , typename An = <em>unspecified</em> 50 > 51struct <a href="./apply.html" class="identifier">apply</a> 52{ 53 typedef <em>unspecified</em> type; 54}; 55</pre> 56</div> 57<div class="section" id="id888"> 58<h3><a class="subsection-title" href="#description" name="description">Description</a></h3> 59<p>Invokes a <a class="reference internal" href="./metafunction-class.html">Metafunction Class</a> or a <a class="reference internal" href="./lambda-expression.html">Lambda Expression</a> <tt class="literal"><span class="pre">F</span></tt> with arguments <tt class="literal"><span class="pre">A1</span></tt>,... <tt class="literal"><span class="pre">An</span></tt>.</p> 60</div> 61<div class="section" id="id889"> 62<h3><a class="subsection-title" href="#header" name="header">Header</a></h3> 63<pre class="literal-block"> 64#include <<a href="../../../../boost/mpl/apply.hpp" class="header">boost/mpl/apply.hpp</a>> 65</pre> 66</div> 67<div class="section" id="id890"> 68<h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3> 69<table border="1" class="docutils table"> 70<colgroup> 71<col width="15%" /> 72<col width="36%" /> 73<col width="48%" /> 74</colgroup> 75<thead valign="bottom"> 76<tr><th class="head">Parameter</th> 77<th class="head">Requirement</th> 78<th class="head">Description</th> 79</tr> 80</thead> 81<tbody valign="top"> 82<tr><td><tt class="literal"><span class="pre">F</span></tt></td> 83<td><a class="reference internal" href="./lambda-expression.html">Lambda Expression</a></td> 84<td>An expression to invoke.</td> 85</tr> 86<tr><td><tt class="literal"><span class="pre">A1</span></tt>,... <tt class="literal"><span class="pre">An</span></tt></td> 87<td>Any type</td> 88<td>Invocation arguments.</td> 89</tr> 90</tbody> 91</table> 92</div> 93<div class="section" id="id891"> 94<h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> 95<p>For any <a class="reference internal" href="./lambda-expression.html">Lambda Expression</a> <tt class="literal"><span class="pre">f</span></tt> and arbitrary types <tt class="literal"><span class="pre">a1</span></tt>,... <tt class="literal"><span class="pre">an</span></tt>:</p> 96<pre class="literal-block"> 97typedef <a href="./apply.html" class="identifier">apply</a><em>n</em><f,a1,<em>...</em>a<em>n</em>>::type t; 98typedef <a href="./apply.html" class="identifier">apply</a><f,a1,<em>...</em>a<em>n</em>>::type t; 99</pre> 100<table class="docutils field-list" frame="void" rules="none"> 101<col class="field-name" /> 102<col class="field-body" /> 103<tbody valign="top"> 104<tr class="field"><th class="field-name">Return type:</th><td class="field-body">Any type.</td> 105</tr> 106<tr class="field"><th class="field-name">Semantics:</th><td class="field-body">Equivalent to <tt class="literal"><span class="pre">typedef</span> <span class="pre"><a href="./apply-wrap.html" class="identifier">apply_wrap</a></span></tt><em>n</em><tt class="literal"><span class="pre"><</span> <span class="pre"><a href="./lambda.html" class="identifier">lambda</a><f>::type,a1,...</span> <span class="pre">an>::type</span> <span class="pre">t;</span></tt>.</td> 107</tr> 108</tbody> 109</table> 110</div> 111<div class="section" id="id892"> 112<h3><a class="subsection-title" href="#example" name="example">Example</a></h3> 113<pre class="literal-block"> 114template< typename N1, typename N2 > struct int_plus 115 : <a href="./int.html" class="identifier">int_</a><( N1::value + N2::value )> 116{ 117}; 118 119typedef <a href="./apply.html" class="identifier">apply</a>< int_plus<<a href="./placeholders.html" class="identifier">_1</a>,<a href="./placeholders.html" class="identifier">_2</a>>, <a href="./int.html" class="identifier">int_</a><2>, <a href="./int.html" class="identifier">int_</a><3> >::type r1; 120typedef <a href="./apply.html" class="identifier">apply</a>< <a href="./quote.html" class="identifier">quote</a><tt class="literal"><span class="pre">2</span></tt><int_plus>, <a href="./int.html" class="identifier">int_</a><2>, <a href="./int.html" class="identifier">int_</a><3> >::type r2; 121 122<a href="./assert-relation.html" class="identifier">BOOST_MPL_ASSERT_RELATION</a>( r1::value, ==, 5 ); 123<a href="./assert-relation.html" class="identifier">BOOST_MPL_ASSERT_RELATION</a>( r2::value, ==, 5 ); 124</pre> 125</div> 126<div class="section" id="id893"> 127<h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> 128<p><a class="reference internal" href="./metafunctions.html">Metafunctions</a>, <a class="reference internal" href="./apply-wrap.html">apply_wrap</a>, <a class="reference internal" href="./lambda.html">lambda</a>, <a class="reference internal" href="./quote.html">quote</a>, <a class="reference internal" href="./bind.html">bind</a></p> 129<!-- Metafunctions/Invocation//apply_wrap |20 --> 130</div> 131</div> 132 133<div class="footer-separator"></div> 134<table class="footer"><tr class="footer"><td class="header-group navigation-bar"><span class="navigation-group"><a href="./invocation.html" class="navigation-link">Prev</a> <a href="./apply-wrap.html" class="navigation-link">Next</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group">Back <a href="./apply-wrap.html" class="navigation-link">Along</a></span><span class="navigation-group-separator"> | </span><span class="navigation-group"><a href="./invocation.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> 135<td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div> 136Distributed under the Boost Software License, Version 1.0. (See accompanying 137file 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> 138</html> 139