Re: Warning 303: %extend defined for an undeclared class opencascade::handle.

> On 27 Jul 2020, at 11.18, Kustaa Nyholm <[email protected]> wrote:
> 
> I get the 303 for following, although the test_ball seems to compile fine?
> 
> I just can't figure this out.
> 
> 
> %{
> #include <Standard_Transient.hxx>
> 
> opencascade::handle<int> test_ball;
> 
> %}
> 
> %extend opencascade::handle
> {
> 
> };
> 
> I've looked into Standard_Transient.hxx and there handle is forward declared as:
> 
> namespace opencascade {
>  template <class T> class handle;
> }
> 
> I cannot seem to find the actual class def for handle though.
> 
> wbr Kusti
> 

Found the actual class def and I think I know how to solve this, but
I still not understand why the above does not work.

First of all I figure I should be working on class 'Standard_Handle', not handle,
but to make it work I need to introduce Standard_Handle to SWIG like this:


class Standard_Handle {
    Standard_Handle()=0;
};

%ignore operator Standard_Transient*();

%extend Standard_Handle
{
    operator Standard_Transient* ()
    {
      return static_cast<Standard_Transient*>(this);
    }

};


And this is because the actual header that contains the declaration is never seen by
SWIG cause I'm / the SWIG .i files I'm working on do not feed that/those headers to it, right?
The include above is only processed by the C++ compiler.

Ok, so above produces no warnings, however it does not fix the actual problem
I'm having but I will make an other post of it.

wbr Kusti