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<font size="6" face="Verdana, Arial, Helvetica, sans-serif"><b>Basic Interface</b></font>
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<p>
Class <tt>object</tt> wraps <tt>PyObject*</tt>. All the intricacies of dealing with
<tt>PyObject</tt>s such as managing reference counting are handled by the
<tt>object</tt> class. C++ object interoperability is seamless. Boost.Python C++
<tt>object</tt>s can in fact be explicitly constructed from any C++ object.</p>
<p>
To illustrate, this Python code snippet:</p>
<code><pre>
<span class=identifier>def </span><span class=identifier>f</span><span class=special>(</span><span class=identifier>x</span><span class=special>, </span><span class=identifier>y</span><span class=special>):
</span><span class=keyword>if </span><span class=special>(</span><span class=identifier>y </span><span class=special>== </span><span class=literal>'foo'</span><span class=special>):
</span><span class=identifier>x</span><span class=special>[</span><span class=number>3</span><span class=special>:</span><span class=number>7</span><span class=special>] = </span><span class=literal>'bar'
</span><span class=keyword>else</span><span class=special>:
</span><span class=identifier>x</span><span class=special>.</span><span class=identifier>items </span><span class=special>+= </span><span class=identifier>y</span><span class=special>(</span><span class=number>3</span><span class=special>, </span><span class=identifier>x</span><span class=special>)
</span><span class=keyword>return </span><span class=identifier>x
</span><span class=identifier>def </span><span class=identifier>getfunc</span><span class=special>():
</span><span class=keyword>return </span><span class=identifier>f</span><span class=special>;
</span></pre></code>
<p>
Can be rewritten in C++ using Boost.Python facilities this way:</p>
<code><pre>
<span class=identifier>object </span><span class=identifier>f</span><span class=special>(</span><span class=identifier>object </span><span class=identifier>x</span><span class=special>, </span><span class=identifier>object </span><span class=identifier>y</span><span class=special>) {
</span><span class=keyword>if </span><span class=special>(</span><span class=identifier>y </span><span class=special>== </span><span class=string>"foo"</span><span class=special>)
</span><span class=identifier>x</span><span class=special>.</span><span class=identifier>slice</span><span class=special>(</span><span class=number>3</span><span class=special>,</span><span class=number>7</span><span class=special>) = </span><span class=string>"bar"</span><span class=special>;
</span><span class=keyword>else
</span><span class=identifier>x</span><span class=special>.</span><span class=identifier>attr</span><span class=special>(</span><span class=string>"items"</span><span class=special>) += </span><span class=identifier>y</span><span class=special>(</span><span class=number>3</span><span class=special>, </span><span class=identifier>x</span><span class=special>);
</span><span class=keyword>return </span><span class=identifier>x</span><span class=special>;
}
</span><span class=identifier>object </span><span class=identifier>getfunc</span><span class=special>() {
</span><span class=keyword>return </span><span class=identifier>object</span><span class=special>(</span><span class=identifier>f</span><span class=special>);
}
</span></pre></code>
<p>
Apart from cosmetic differences due to the fact that we are writing the
code in C++, the look and feel should be immediately apparent to the Python
coder.</p>
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<hr size="1"><p class="copyright">Copyright © 2002-2003 David Abrahams<br>Copyright © 2002-2003 Joel de Guzman<br><br>
<font size="2">Permission to copy, use, modify, sell and distribute this document
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