https://svn.boost.org/trac10/ticket/3 <pre class="wiki">When overload is used, if functions whose parameters use automatic conversions are declared first, the functinos whose parameters are wrapped extension classes do not resolve. I attached a file which demonstrates what happens. Two automatic conversions are defined, on GeVector2 and GeVector3. Then 3 overloaded functions are defined and exposed, the first two using the automatic conversions from above, and the third using a simple Foo class. When the functions using the automatic conversions are declared after the function taking Foo as a parameter, it all works. Here is your test program: import prob f = prob.Foo() print prob.testfoo( f ) However, the automatic conversions work between themselves (i.e. a failed conversion to a GeVector2 when trying to convert a GeVector3 will not fail the conversion to GeVector3). I also found that by throwing the exception unconditinoally at the beginning of the conversion functions makes it work for the wrapped ext.class. This indicates that the following code is the culprit: // Convert from a list of two. boost::python::list l = from_python( p, boost::python::type&lt;boost::python::list&gt;() ); runnign that makes the subsequent intent to convert to a wrapped class fail somehow. Any idea? </pre> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/3 Trac 1.4.3 blais Mon, 24 Sep 2001 22:16:44 GMT https://svn.boost.org/trac10/ticket/3#comment:3 https://svn.boost.org/trac10/ticket/3#comment:3 <ul> <li><strong>status</strong> <span class="trac-field-old">assigned</span> → <span class="trac-field-new">closed</span> </li> </ul> Ticket Robert Ramey Fri, 11 Jun 2010 04:11:25 GMT https://svn.boost.org/trac10/ticket/3#comment:4 https://svn.boost.org/trac10/ticket/3#comment:4 <ul> <li><strong>resolution</strong> <span class="trac-field-old">None</span> → <span class="trac-field-new">fixed</span> </li> </ul> <p> (In <a class="changeset" href="https://svn.boost.org/trac10/changeset/62785" title="fix #3 for version_type">[62785]</a>) fix <a class="closed ticket" href="https://svn.boost.org/trac10/ticket/3" title="#3: Bugs: automatic conversion and overload proble (closed: fixed)">#3</a> for version_type </p> Ticket Robert Ramey Fri, 11 Jun 2010 04:12:47 GMT https://svn.boost.org/trac10/ticket/3#comment:6 https://svn.boost.org/trac10/ticket/3#comment:6 <ul> <li><strong>severity</strong> → <span class="trac-field-new">Problem</span> </li> </ul> <p> hello world </p> Ticket