Smalltalk and Python

[Steve Williams]

Andrew Dalke wrote:

> Greg Ewing wrote:
> >the TADS (Text Adventure Development System)
> >lets you declare objects with multiple
> >classes, e.g.
> >
> >   bed: Furniture, Surface, Scenery
> >      ...
> ...
> >This is really just syntactic sugar,
> ...
> >To mention something vaguely Python-relevant:
> >if Python had a convenient syntax for declaring
> >singletons, it could be a pretty good language for
> >Interactive Fiction...
>
> One packet of syntactic sugar, coming up!
>
> def make_a(*classes):
>   class make_a:
>     pass
>   make_a.__bases__ = tuple(classes)
>   return make_a()
>
> class Furniture:
>      def comfy(self): return 1
>
> class Surface:
>     def genus(self): return 0  # Imagine a spherical cow...
>
> class Scenery:
>     def description(self): return "boring"
>
> >>> bed = make_a(Furniture, Surface, Scenery)
> >>> bed
> <__main__.make_a instance at 0x120330628>
> >>> bed.description()
> 'boring'
> >>> bed.genus()
> 0
> >>> bed.comfy()
> 1
> >>>
>
>                     Andrew
>                     dalke at acm.org

A cow is genus 1