Example after selecting a component instance:
mod = Sketchup::active_model ents = mod.entities c = mod.selection b = c.bounds # ents.add_face( b, b, b, b )
Currently I have to define a singleton method (where the comment is,) like:
def b.(arg); self.corner(arg); end
It is more intuitive that the
 method accesses the box’s corners.