[Insight-users] Re: extend classes with cableswig

[Brad King]

Gaetan Lehmann wrote:
> swig allow to extend classes with the keyword %extend.
> 
> I want to implement methods such as __getitem__, __setitem__ and 
> __len__  in Size, Index, Array and FixedArray classes, so those basic 
> objects can  be accessed with native python interface, and with bound 
> checking, which  is more python user friendly. Adding __repr__ or 
> __str__ method to those  classes would also allow user to easily see the 
> content of objects of  those classes...
> Also, I want to implement __str__ in LighObject class, to return the  
> string produced by the Print method, so lots of itk objects can be 
> printed  with "print anItkObject"
> 
> Sadely, with cableswig, it seems %extend have no effect. Do you know why ?
> What can be done to extend classes ? Currently, I'm adding all those  
> method directly in .h files...

I think you're stuck for now.  The "right" way to do this is to get rid 
of CableSwig and extend standard SWIG with a %xml(gccxml) option to 
import a gccxml dump.  Then all the standard swig stuff will work 
properly.  I think this approach will be much better than trying to get 
all the swig extension syntax into CableSwig.

-Brad