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<font size="6" face="Verdana, Arial, Helvetica, sans-serif"><b>Reducing Compiling Time</b></font>
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<p>
If you have ever exported a lot of classes, you know that it takes quite a good
time to compile the Boost.Python wrappers. Plus the memory consumption can
easily become too high. If this is causing you problems, you can split the
class_ definitions in multiple files:</p>
<code><pre>
<span class=comment>/* file point.cpp */
</span><span class=preprocessor>#include </span><span class=special><</span><span class=identifier>point</span><span class=special>.</span><span class=identifier>h</span><span class=special>>
</span><span class=preprocessor>#include </span><span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>python</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>>
</span><span class=keyword>void </span><span class=identifier>export_point</span><span class=special>()
{
</span><span class=identifier>class_</span><span class=special><</span><span class=identifier>point</span><span class=special>>(</span><span class=string>"point"</span><span class=special>)...;
}
/* </span><span class=identifier>file </span><span class=identifier>triangle</span><span class=special>.</span><span class=identifier>cpp </span><span class=special>*/
</span><span class=preprocessor>#include </span><span class=special><</span><span class=identifier>triangle</span><span class=special>.</span><span class=identifier>h</span><span class=special>>
</span><span class=preprocessor>#include </span><span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>python</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>>
</span><span class=keyword>void </span><span class=identifier>export_triangle</span><span class=special>()
{
</span><span class=identifier>class_</span><span class=special><</span><span class=identifier>triangle</span><span class=special>>(</span><span class=string>"triangle"</span><span class=special>)...;
}
</span></pre></code>
<p>
Now you create a file <tt>main.cpp</tt>, which contains the <tt>BOOST_PYTHON_MODULE</tt>
macro, and call the various export functions inside it. </p>
<code><pre>
<span class=keyword>void </span><span class=identifier>export_point</span><span class=special>();
</span><span class=keyword>void </span><span class=identifier>export_triangle</span><span class=special>();
</span><span class=identifier>BOOST_PYTHON_MODULE</span><span class=special>(</span><span class=identifier>_geom</span><span class=special>)
{
</span><span class=identifier>export_point</span><span class=special>();
</span><span class=identifier>export_triangle</span><span class=special>();
}
</span></pre></code>
<p>
Compiling and linking together all this files produces the same result as the
usual approach:</p>
<code><pre>
<span class=preprocessor>#include </span><span class=special><</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>python</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>>
</span><span class=preprocessor>#include </span><span class=special><</span><span class=identifier>point</span><span class=special>.</span><span class=identifier>h</span><span class=special>>
</span><span class=preprocessor>#include </span><span class=special><</span><span class=identifier>triangle</span><span class=special>.</span><span class=identifier>h</span><span class=special>>
</span><span class=identifier>BOOST_PYTHON_MODULE</span><span class=special>(</span><span class=identifier>_geom</span><span class=special>)
{
</span><span class=identifier>class_</span><span class=special><</span><span class=identifier>point</span><span class=special>>(</span><span class=string>"point"</span><span class=special>)...;
</span><span class=identifier>class_</span><span class=special><</span><span class=identifier>triangle</span><span class=special>>(</span><span class=string>"triangle"</span><span class=special>)...;
}
</span></pre></code>
<p>
but the memory is kept under control. </p>
<p>
This method is recommended too if you are developing the C++ library and
exporting it to Python at the same time: changes in a class will only demand
the compilation of a single cpp, instead of the entire wrapper code.</p>
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<td class="note_box">
<img src="theme/note.gif"></img> If you're exporting your classes with <a href="../../../pyste/index.html">
Pyste</a>,
take a look at the <tt>--multiple</tt> option, that generates the wrappers in
various files as demonstrated here. </td>
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<td class="note_box">
<img src="theme/note.gif"></img> This method is useful too if you are getting the error message
<i>"fatal error C1204:Compiler limit:internal structure overflow"</i> when compiling
a large source file, as explained in the <a href="../../v2/faq.html#c1204">
FAQ</a>. </td>
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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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