<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <title>Struct _value</title> <link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> <meta name="generator" content="DocBook XSL Stylesheets V1.75.2"> <link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> <link rel="up" href="../../proto/reference.html#header.boost.proto.transform.arg_hpp" title="Header <boost/proto/transform/arg.hpp>"> <link rel="prev" href="_child_c/impl.html" title="Struct template impl"> <link rel="next" href="_value/impl.html" title="Struct template impl"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <table cellpadding="2" width="100%"><tr> <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../boost.png"></td> <td align="center"><a href="../../../../index.html">Home</a></td> <td align="center"><a 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class="link" href="../../PrimitiveTransform.html" title="Concept PrimitiveTransform">PrimitiveTransform</a> that returns the value of the current terminal expression. </p> </div> <h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> <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.transform.arg_hpp" title="Header <boost/proto/transform/arg.hpp>">boost/proto/transform/arg.hpp</a>> </span> <span class="keyword">struct</span> <a class="link" href="_value.html" title="Struct _value">_value</a> <span class="special">:</span> <span class="keyword"></span> <a class="link" href="transform.html" title="Struct template transform">proto::transform</a><span class="special"><</span> <span class="identifier">_value</span> <span class="special">></span> <span class="special">{</span> <span class="comment">// member classes/structs/unions</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> <span class="keyword">typename</span> State<span class="special">,</span> <span class="keyword">typename</span> Data<span class="special">></span> <span class="keyword">struct</span> <a class="link" href="_value/impl.html" title="Struct template impl">impl</a> <span class="special">:</span> <span class="keyword"></span> <a class="link" href="transform_impl.html" title="Struct template transform_impl">proto::transform_impl</a><span class="special"><</span> <span class="identifier">Expr</span><span class="special">,</span> <span class="identifier">State</span><span class="special">,</span> <span class="identifier">Data</span> <span class="special">></span> <span class="special">{</span> <span class="comment">// types</span> <span class="keyword">typedef</span> <span class="keyword">typename</span> <a class="link" href="result_of/value.html" title="Struct template value">proto::result_of::value</a><span class="special"><</span> <span class="identifier">Expr</span> <span class="special">></span><span class="special">::</span><span class="identifier">type</span> <a class="link" href="_value/impl.html#boost.proto._value.impl.result_type"><span class="identifier">result_type</span></a><span class="special">;</span> <span class="comment">// <a class="link" href="_value/impl.html#id1286772-bb">public member functions</a></span> <span class="keyword">typename</span> <a class="link" href="result_of/value.html" title="Struct template value">proto::result_of::value</a><span class="special"><</span> <span class="identifier">Expr</span> <span class="special">></span><span class="special">::</span><span class="identifier">type</span> <a class="link" href="_value/impl.html#id1286777-bb"><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span></a><span class="special">(</span><span class="keyword">typename</span> <span class="identifier">impl</span><span class="special">::</span><span class="identifier">expr_param</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">impl</span><span class="special">::</span><span class="identifier">state_param</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">impl</span><span class="special">::</span><span class="identifier">data_param</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> <span class="special">}</span><span class="special">;</span> <span class="special">}</span><span class="special">;</span></pre></div> <div class="refsect1"> <a name="id2428329"></a><h2>Description</h2> <p> Example: </p> <pre class="programlisting"><a class="link" href="terminal.html" title="Struct template terminal">proto::terminal</a><span class="special"><</span><span class="keyword">int</span><span class="special">></span><span class="special">::</span><span class="identifier">type</span> <span class="identifier">i</span> <span class="special">=</span> <span class="special">{</span><span class="number">42</span><span class="special">}</span><span class="special">;</span> <span class="keyword">int</span> <span class="identifier">j</span> <span class="special">=</span> <span class="identifier">proto</span><span class="special">::</span><span class="identifier">_value</span><span class="special">(</span><span class="special">)</span><span class="special">(</span><span class="identifier">i</span><span class="special">)</span><span class="special">;</span> <span class="identifier">assert</span><span class="special">(</span> <span class="number">42</span> <span class="special">==</span> <span class="identifier">j</span> <span class="special">)</span><span class="special">;</span></pre> <p> </p> </div> </div> <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> <td align="left"></td> <td align="right"><div class="copyright-footer">Copyright © 2008 Eric Niebler<p> Distributed under the Boost Software License, Version 1.0. (See accompanying 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>) </p> </div></td> </tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="_child_c/impl.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../proto/reference.html#header.boost.proto.transform.arg_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="_value/impl.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> </div> </body> </html>