Sounds reasonable to me. I am a little concerned about the number of
classes, but I guess it's only one extra class per decorator which isn't
too bad.
We had many of those classes anyway as XYZs sort of classes were sporadically defined. So it doesn't really add much. The class definitions are more complicated though.
Ben, can such be made to work on the python side too via typemaps? I had
looked at doing implicit conversions at some point and couldn't quite
figure out how to make it work.
In principle if it works in C++ it should work automatically in Python -
SWIG usually does a reasonable job at figuring out which types can be
cast to others. If not, we can certainly fix it so that it does work.
Swig doesn't handle conversion operators (ie Decorator::operator Particle*()). We should be able to do the same with typemaps, but not all of the modules have the swig type info for Decorator and so the code to check if something is a decorator and, if so, cast it to a particle, doesn't compile.