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 as_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.traits_hpp" title="Header <boost/proto/traits.hpp>"> 10<link rel="prev" href="../functional/right/resu_1_3_33_5_39_2_1_4_7_2.html" title="Struct template result<This(Expr)>"> 11<link rel="next" href="as_child.html" title="Struct template as_child"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../boost.png"></td> 16<td align="center"><a href="../../../../../index.html">Home</a></td> 17<td align="center"><a href="../../../../../libs/libraries.htm">Libraries</a></td> 18<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 19<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 20<td align="center"><a href="../../../../../more/index.htm">More</a></td> 21</tr></table> 22<hr> 23<div class="spirit-nav"> 24<a accesskey="p" href="../functional/right/resu_1_3_33_5_39_2_1_4_7_2.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../proto/reference.html#header.boost.proto.traits_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="as_child.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="refentry"> 27<a name="boost.proto.result_of.as_expr"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Struct template as_expr</span></h2> 30<p>boost::proto::result_of::as_expr — A metafunction that computes the return type of the 31 <code class="computeroutput"><a class="link" href="../as_expr.html" title="Function as_expr">proto::as_expr</a>()</code> function.</p> 32</div> 33<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 34<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.traits_hpp" title="Header <boost/proto/traits.hpp>">boost/proto/traits.hpp</a>> 35 36</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> T<span class="special">,</span> <span class="keyword">typename</span> <a class="link" href="../../../Domain.html" title="Concept Domain">Domain</a> <span class="special">=</span> <a class="link" href="../default_domain.html" title="Struct default_domain">proto::default_domain</a><span class="special">></span> 37<span class="keyword">struct</span> <a class="link" href="as_expr.html" title="Struct template as_expr">as_expr</a> <span class="special">{</span> 38 <span class="comment">// types</span> 39 <span class="keyword">typedef</span> <span class="keyword">typename</span> <span class="identifier">Domain</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">as_expr</span><span class="special"><</span> <span class="identifier">T</span> <span class="special">></span><span class="special">::</span><span class="identifier">result_type</span> <a name="boost.proto.result_of.as_expr.type"></a><span class="identifier">type</span><span class="special">;</span> 40<span class="special">}</span><span class="special">;</span></pre></div> 41<div class="refsect1"> 42<a name="id-1.3.33.5.41.11.4"></a><h2>Description</h2> 43<p> 44 The <code class="computeroutput">proto::result_of::as_expr<></code> metafunction turns types 45 into Proto expression types, if they are not already, in a domain-specific way. It is intended 46 for use to compute the type of a local variable that can hold the result of the 47 <code class="computeroutput"><a class="link" href="../as_expr.html" title="Function as_expr">proto::as_expr</a>()</code> function. 48 </p> 49<p> 50 See <code class="computeroutput"><a class="link" href="../domain/as_expr.html" title="Struct template as_expr">proto::domain::as_expr</a><></code> 51 for a complete description of the default behavior. 52 </p> 53</div> 54</div> 55<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 56<td align="left"></td> 57<td align="right"><div class="copyright-footer">Copyright © 2008 Eric Niebler<p> 58 Distributed under the Boost Software License, Version 1.0. (See accompanying 59 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>) 60 </p> 61</div></td> 62</tr></table> 63<hr> 64<div class="spirit-nav"> 65<a accesskey="p" href="../functional/right/resu_1_3_33_5_39_2_1_4_7_2.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../proto/reference.html#header.boost.proto.traits_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="as_child.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> 66</div> 67</body> 68</html> 69
