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 unexpr</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.expr_hpp" title="Header <boost/proto/expr.hpp>"> 10<link rel="prev" href="expr/result.html" title="Struct template result"> 11<link rel="next" href="is_proto_expr.html" title="Struct is_proto_expr"> 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="expr/result.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../proto/reference.html#header.boost.proto.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="is_proto_expr.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 25</div> 26<div class="refentry"> 27<a name="boost.proto.unexpr"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Struct template unexpr</span></h2> 30<p>boost::proto::unexpr — Lets you inherit the interface of an expression while hiding from Proto the fact that 31 the type is a Proto expression.</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.expr_hpp" title="Header <boost/proto/expr.hpp>">boost/proto/expr.hpp</a>> 35 36</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> <a class="link" href="../../Expr.html" title="Concept Expr">Expr</a><span class="special">></span> 37<span class="keyword">struct</span> <a class="link" href="unexpr.html" title="Struct template unexpr">unexpr</a> <span class="special">:</span> <span class="keyword"></span> Expr <span class="special">{</span> 38 <span class="comment">// <a class="link" href="unexpr.html#boost.proto.unexprconstruct-copy-destruct">construct/copy/destruct</a></span> 39 <a class="link" href="unexpr.html#id-1_3_33_5_9_1_1_3_5-bb"><span class="identifier">unexpr</span></a><span class="special">(</span><span class="identifier">Expr</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 40<span class="special">}</span><span class="special">;</span></pre></div> 41<div class="refsect1"> 42<a name="id-1.3.33.5.11.5.4"></a><h2>Description</h2> 43<p> 44 For an expression type <code class="computeroutput">E</code>, 45 <code class="computeroutput"> 46 <a class="link" href="is_expr.html" title="Struct template is_expr">proto::is_expr</a><E>::value 47 </code> is <code class="computeroutput">true</code>, but 48 <code class="computeroutput"> 49 <a class="link" href="is_expr.html" title="Struct template is_expr">proto::is_expr</a><proto::unexpr<E> >::value 50 </code> is <code class="computeroutput">false</code>. 51 </p> 52<div class="refsect2"> 53<a name="id-1.3.33.5.11.5.4.3"></a><h3> 54<a name="boost.proto.unexprconstruct-copy-destruct"></a><code class="computeroutput">unexpr</code> 55 public 56 construct/copy/destruct</h3> 57<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><pre class="literallayout"><a name="id-1_3_33_5_9_1_1_3_5-bb"></a><span class="identifier">unexpr</span><span class="special">(</span><span class="identifier">Expr</span> <span class="keyword">const</span> <span class="special">&</span> expr<span class="special">)</span><span class="special">;</span></pre></li></ol></div> 58</div> 59</div> 60</div> 61<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 62<td align="left"></td> 63<td align="right"><div class="copyright-footer">Copyright © 2008 Eric Niebler<p> 64 Distributed under the Boost Software License, Version 1.0. (See accompanying 65 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>) 66 </p> 67</div></td> 68</tr></table> 69<hr> 70<div class="spirit-nav"> 71<a accesskey="p" href="expr/result.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../proto/reference.html#header.boost.proto.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="is_proto_expr.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 72</div> 73</body> 74</html> 75
