Re: [Swig-user] directorargout: removing unneeded arguments

[Bob H. <bh...@co...>]

Bump.

On 5/8/2014 2:02 PM, Bob Hood wrote:
> I'm using SWIG 2.0.4 with Python.
>
> I've run into the first instance where I need to have an 'argout' mechanism
> for a Director-controlled method.  Something along these lines:
>
>     typedef double Vector[3];
>     ...
>     class MyClass
>     {
>        ...
>        virtual int get_pos(Vector v);    // <-- 'v' is an output-onlyargument
>     };
>
> with
>
>     %feature("director") MyClass;
>
> in the interface file.
>
> I've applied the "%typemap(directorargout) Vector" and achieved the desired
> effect.  However, it appears that the generated Python method continues to
> require the Vector 'v' argument to the method, even though it serves no useful
> purposeand is not of a known type to Python; e.g. this works properly:
>
>     def get_pos(self, v):
>         return (1, (0, 0, 0))
>
> However, if I attempt to leave off the 'v' argument:
>
>     def get_pos(self):
>         return (1, (0, 0, 0))
>
> I get an error about the method requiring 1 argument with 2 provided.  Is
> there a way that I can tell SWIG that the Python-based argument is irrelevant
> (perhaps using some kind of %ignore directive) and that it should not attempt
> to pass it to the Python code when invoking PyObject_CallMethod()?