[C++-sig] [boost.python] Can't import a wrapped template class

[Paul O. Seidon]

Stefan Seefeld wrote:

> On 10/26/2012 02:24 PM, Paul O. Seidon wrote:
>> Paul O.  Seidon wrote:
>>
>> That doesn't do it either. I can't help but post the compete code here to
>> be sure I'm not misunderstood. The lib consists of varbls.cpp and
>> varbls.h and the wrapper main.cpp.
> 
>> varbls.cpp
>> ==========
>>
>> #include "varbls.h"
>>
>>
>> template <typename TYPE>
>> _Variable<TYPE>::_Variable()
>> : _value( 0)
>> {
>>     //ctor
>> }
> 
> [...]
> 
> What symbols does your compiled varbls.o file export ? I bet none. And
> it can't. That's the problem I'm trying to explain.
> 
>     Stefan
> 

As Alex said, this seems to be a C++ issue. Hope you'll help me 
nevertheless. There can't be that much that's missing.

How do I do that export?

This whole mess is caused by the use of a template class. You see, there's a 
class VariableFloat. It is not a template class and is not derived from a 
template class. And it works, I can use it from w/i my Python modules. Well, 
it's deactivated for now to prevent "side effects".

Yes, I have to provide a TYPE to the tempate to enable the compiler to 
generate code. Isn't 

typedef _Variable<double>  VariableDouble;

BOOST_PYTHON_MODULE(_varbls)
{

    class_<VariableDouble>("VariableDouble")
        .def( init<>())
        .def( init<const double&>())
    ;
}

doing that?

Paul