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Also port some "glaringly obvious" bugfixes from HEAD. Hope it doesn't cause problems. [SVN r35237]
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80 lines
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<!-- Generated by the Spirit (http://spirit.sf.net) QuickDoc -->
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<title>Adding New Methods</title>
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<font size="6" face="Verdana, Arial, Helvetica, sans-serif"><b>Adding New Methods</b></font>
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<p>
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Suppose that you want to add a function to a class, turning it into a member
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function:</p>
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<code><pre>
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<span class=keyword>struct </span><span class=identifier>World
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</span><span class=special>{
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</span><span class=keyword>void </span><span class=identifier>set</span><span class=special>(</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>string </span><span class=identifier>msg</span><span class=special>) { </span><span class=keyword>this</span><span class=special>-></span><span class=identifier>msg </span><span class=special>= </span><span class=identifier>msg</span><span class=special>; }
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</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>string </span><span class=identifier>msg</span><span class=special>;
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};
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</span><span class=identifier>std</span><span class=special>::</span><span class=identifier>string </span><span class=identifier>greet</span><span class=special>(</span><span class=identifier>World</span><span class=special>& </span><span class=identifier>w</span><span class=special>)
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{
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</span><span class=keyword>return </span><span class=identifier>w</span><span class=special>.</span><span class=identifier>msg</span><span class=special>;
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}
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</span></pre></code>
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<p>
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Here, we want to make <tt>greet</tt> work as a member function of the class <tt>World</tt>. We do
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that using the <tt>add_method</tt> construct:</p>
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<code><pre>
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<span class=identifier>W </span><span class=special>= </span><span class=identifier>Class</span><span class=special>(</span><span class=string>"World"</span><span class=special>, </span><span class=string>"hello.h"</span><span class=special>)
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</span><span class=identifier>add_method</span><span class=special>(</span><span class=identifier>W</span><span class=special>, </span><span class=string>"greet"</span><span class=special>)
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</span></pre></code>
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<p>
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Notice also that then you can rename it, set its policy, just like a regular
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member function:</p>
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<code><pre>
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<span class=identifier>rename</span><span class=special>(</span><span class=identifier>W</span><span class=special>.</span><span class=identifier>greet</span><span class=special>, </span><span class=literal>'Greet'</span><span class=special>)
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</span></pre></code>
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<p>
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Now from Python:</p>
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<code><pre>
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<span class=special>>>> </span><span class=identifier>import </span><span class=identifier>hello
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</span><span class=special>>>> </span><span class=identifier>w </span><span class=special>= </span><span class=identifier>hello</span><span class=special>.</span><span class=identifier>World</span><span class=special>()
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>>> </span><span class=identifier>w</span><span class=special>.</span><span class=identifier>set</span><span class=special>(</span><span class=literal>'Ni'</span><span class=special>)
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>>> </span><span class=identifier>w</span><span class=special>.</span><span class=identifier>greet</span><span class=special>()
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</span><span class=literal>'Ni'
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</span><span class=special>>>> </span><span class=identifier>print </span><span class=literal>'Oh no! The knights who say Ni!'
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</span><span class=identifier>Oh </span><span class=identifier>no</span><span class=special>! </span><span class=identifier>The </span><span class=identifier>knights </span><span class=identifier>who </span><span class=identifier>say </span><span class=identifier>Ni</span><span class=special>!
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</span></pre></code>
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<br>
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<hr size="1"><p class="copyright">Copyright © 2003 Bruno da Silva de Oliveira<br>Copyright © 2002-2003 Joel de Guzman<br><br>
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<font size="2">Distributed under
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the Boost Software License, Version 1.0. (See accompanying file
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LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) </font> </p>
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