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| <p> |
| References are functions. They hold a reference to a value stored somewhere. |
| For example, given: |
| </p> |
| <pre class="programlisting"><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">3</span><span class="special">;</span> |
| <span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">s</span> <span class="special">=</span> <span class="string">"Hello World"</span><span class="special">;</span> |
| </pre> |
| <p> |
| we create <code class="computeroutput"><span class="identifier">references</span></code> to |
| <code class="computeroutput"><span class="identifier">i</span></code> and <code class="computeroutput"><span class="identifier">s</span></code> |
| this way: |
| </p> |
| <pre class="programlisting"><span class="identifier">ref</span><span class="special">(</span><span class="identifier">i</span><span class="special">)</span> |
| <span class="identifier">ref</span><span class="special">(</span><span class="identifier">s</span><span class="special">)</span> |
| </pre> |
| <p> |
| Like <code class="computeroutput"><span class="identifier">val</span></code>, the expressions |
| above evaluates to a nullary function; the first one returning an <code class="computeroutput"><span class="keyword">int</span><span class="special">&</span></code>, |
| and the second one returning a <code class="computeroutput"><span class="keyword">char</span> |
| <span class="keyword">const</span><span class="special">*&</span></code>. |
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| <p> |
| (See <a href="../../../../../example/references.cpp" target="_top">references.cpp</a>) |
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| <span class="inlinemediaobject"><img src="../../../images/tip.png" alt="tip"></span> Learn more about references <a class="link" href="../../modules/core/references.html" title="References">here.</a> |
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| <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>) |
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