mirror of
https://github.com/boostorg/phoenix.git
synced 2026-02-15 01:12:09 +00:00
68 lines
5.8 KiB
HTML
68 lines
5.8 KiB
HTML
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
|
|
<title>Binding Member Variables</title>
|
|
<link rel="stylesheet" href="../../../boostbook.css" type="text/css">
|
|
<meta name="generator" content="DocBook XSL Stylesheets V1.76.1">
|
|
<link rel="home" href="../../../index.html" title="Chapter 1. Phoenix 3.0">
|
|
<link rel="up" href="../bind.html" title="Bind">
|
|
<link rel="prev" href="binding_member_functions.html" title="Binding Member Functions">
|
|
<link rel="next" href="compatibility_with_other_boost_bind.html" title="Compatibility with other Boost.Bind">
|
|
</head>
|
|
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
|
|
<table cellpadding="2" width="100%"><tr><td valign="top"></td></tr></table>
|
|
<hr>
|
|
<div class="spirit-nav">
|
|
<a accesskey="p" href="binding_member_functions.html"><img src="../../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../bind.html"><img src="../../../images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../images/home.png" alt="Home"></a><a accesskey="n" href="compatibility_with_other_boost_bind.html"><img src="../../../images/next.png" alt="Next"></a>
|
|
</div>
|
|
<div class="section">
|
|
<div class="titlepage"><div><div><h4 class="title">
|
|
<a name="phoenix.modules.bind.binding_member_variables"></a><a class="link" href="binding_member_variables.html" title="Binding Member Variables">Binding
|
|
Member Variables</a>
|
|
</h4></div></div></div>
|
|
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">phoenix</span><span class="special">/</span><span class="identifier">bind</span><span class="special">/</span><span class="identifier">bind_member_variable</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
|
|
</pre>
|
|
<p>
|
|
Member variables can also be bound much like member functions. Member variables
|
|
are not functions. Yet, like the <a class="link" href="../core/references.html" title="References"><code class="computeroutput"><span class="identifier">ref</span><span class="special">(</span><span class="identifier">x</span><span class="special">)</span></code></a>
|
|
that acts like a nullary function returning a reference to the data, member
|
|
variables, when bound, act like a unary function, taking in a pointer or
|
|
reference to an object as its argument and returning a reference to the
|
|
bound member variable. For instance, given:
|
|
</p>
|
|
<pre class="programlisting"><span class="keyword">struct</span> <span class="identifier">xyz</span>
|
|
<span class="special">{</span>
|
|
<span class="keyword">int</span> <span class="identifier">v</span><span class="special">;</span>
|
|
<span class="special">};</span>
|
|
</pre>
|
|
<p>
|
|
<code class="computeroutput"><span class="identifier">xyz</span><span class="special">::</span><span class="identifier">v</span></code> can be bound as:
|
|
</p>
|
|
<pre class="programlisting"><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">xyz</span><span class="special">::</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">obj</span><span class="special">)</span> <span class="comment">// obj is an xyz object
|
|
</span></pre>
|
|
<p>
|
|
As noted, just like the bound member function, a bound member variable
|
|
also expects the first (and only) argument to be a pointer or reference
|
|
to an object. The object (reference or pointer) can be lazily bound. Examples:
|
|
</p>
|
|
<pre class="programlisting"><span class="identifier">xyz</span> <span class="identifier">obj</span><span class="special">;</span>
|
|
<span class="identifier">bind</span><span class="special">(&</span><span class="identifier">xyz</span><span class="special">::</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">arg1</span><span class="special">)</span> <span class="comment">// arg1.v
|
|
</span><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">xyz</span><span class="special">::</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">obj</span><span class="special">)</span> <span class="comment">// obj.v
|
|
</span><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">xyz</span><span class="special">::</span><span class="identifier">v</span><span class="special">,</span> <span class="identifier">arg1</span><span class="special">)(</span><span class="identifier">obj</span><span class="special">)</span> <span class="special">=</span> <span class="number">4</span> <span class="comment">// obj.v = 4
|
|
</span></pre>
|
|
</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 © 2002-2005, 2010 Joel de Guzman, Dan Marsden, Thomas Heller<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="binding_member_functions.html"><img src="../../../images/prev.png" alt="Prev"></a><a accesskey="u" href="../bind.html"><img src="../../../images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../images/home.png" alt="Home"></a><a accesskey="n" href="compatibility_with_other_boost_bind.html"><img src="../../../images/next.png" alt="Next"></a>
|
|
</div>
|
|
</body>
|
|
</html>
|