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>Struct template make_expr</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="../../../proto/reference.html#header.boost.proto.make_expr_hpp" title="Header <boost/proto/make_expr.hpp>"> 10<link rel="prev" href="../functional/unpack_expr/resu_1_3_33_5_31_2_1_1_2_5.html" title="Struct template result<This(Sequence)>"> 11<link rel="next" href="make_e_1_3_33_5_31_2_1_2_2.html" title="Struct template make_expr<Tag, Domain, A...>"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" 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href="make_e_1_3_33_5_31_2_1_2_2.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="refentry"> 27<a name="boost.proto.result_of.make_expr"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Struct template make_expr</span></h2> 30<p>boost::proto::result_of::make_expr — Metafunction that computes the return type of the 31 <code class="computeroutput"><a class="link" href="../make_expr.html" title="Function make_expr">proto::make_expr()</a></code> 32 function, with a domain deduced from the domains of the children.</p> 33</div> 34<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 35<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="../../../proto/reference.html#header.boost.proto.make_expr_hpp" title="Header <boost/proto/make_expr.hpp>">boost/proto/make_expr.hpp</a>> 36 37</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> Tag<span class="special">,</span> <span class="keyword">typename</span><span class="special">...</span> A<span class="special">></span> 38<span class="keyword">struct</span> <a class="link" href="make_expr.html" title="Struct template make_expr">make_expr</a> <span class="special">{</span> 39 <span class="comment">// <a class="link" href="make_expr.html#boost.proto.result_of.make_exprtypes">types</a></span> 40 <span class="keyword">typedef</span> <em class="replaceable"><code><span class="identifier">domain</span><span class="special">-</span><span class="identifier">deduced</span><span class="special">-</span><span class="identifier">from</span><span class="special">-</span><span class="identifier">child</span><span class="special">-</span><span class="identifier">types</span></code></em> <a class="link" href="make_expr.html#boost.proto.result_of.make_expr.D"><span class="identifier">D</span></a><span class="special">;</span> 41 <span class="keyword">typedef</span> <span class="keyword">typename</span> <a class="link" href="make_expr.html" title="Struct template make_expr">proto::result_of::make_expr</a><span class="special"><</span><span class="identifier">Tag</span><span class="special">,</span> <span class="identifier">D</span><span class="special">,</span> <span class="identifier">A</span><span class="special">...</span><span class="special">></span><span class="special">::</span><span class="identifier">type</span> <a name="boost.proto.result_of.make_expr.type"></a><span class="identifier">type</span><span class="special">;</span> 42<span class="special">}</span><span class="special">;</span></pre></div> 43<div class="refsect1"> 44<a name="id-1.3.33.5.33.6.4"></a><h2>Description</h2> 45<p> 46 Computes the return type of the 47 <code class="computeroutput"><a class="link" href="../make_expr.html" title="Function make_expr">proto::make_expr()</a></code> function. 48 </p> 49<p> 50 In this specialization, the domain is deduced from the domains of the child types. 51 If <code class="computeroutput"><a class="link" href="../is_domain.html" title="Struct template is_domain">proto::is_domain</a><A<sub>0</sub>>::value</code> 52 is <code class="computeroutput">true</code>, then another specialization is selected. 53 </p> 54<div class="refsect2"> 55<a name="id-1.3.33.5.33.6.4.4"></a><h3> 56<a name="boost.proto.result_of.make_exprtypes"></a><code class="computeroutput">make_expr</code> 57 public 58 types</h3> 59<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 60<p> 61<span class="keyword">typedef</span> <em class="replaceable"><code><span class="identifier">domain</span><span class="special">-</span><span class="identifier">deduced</span><span class="special">-</span><span class="identifier">from</span><span class="special">-</span><span class="identifier">child</span><span class="special">-</span><span class="identifier">types</span></code></em> <a name="boost.proto.result_of.make_expr.D"></a><span class="identifier">D</span><span class="special">;</span></p> 62<p> 63 In this specialization, Proto uses the domains of the child expressions to compute the 64 domain of the parent. See 65 <code class="computeroutput"><a class="link" href="../deduce_domain.html" title="Struct deduce_domain">proto::deduce_domain</a></code> for a full 66 description of the procedure used. 67 </p> 68</li></ol></div> 69</div> 70</div> 71</div> 72<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 73<td align="left"></td> 74<td align="right"><div class="copyright-footer">Copyright © 2008 Eric Niebler<p> 75 Distributed under the Boost Software License, Version 1.0. (See accompanying 76 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>) 77 </p> 78</div></td> 79</tr></table> 80<hr> 81<div class="spirit-nav"> 82<a accesskey="p" href="../functional/unpack_expr/resu_1_3_33_5_31_2_1_1_2_5.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../proto/reference.html#header.boost.proto.make_expr_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="make_e_1_3_33_5_31_2_1_2_2.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> 83</div> 84</body> 85</html> 86
