1 # code is public domain
   2 import sets
   3 
   4 class Enumeration(object):
   5     
   6     def __new__(cls, arg):
   7         if hasattr(cls, arg):
   8             return getattr(cls,arg)
   9         else:
  10             return object.__new__(cls, arg)
  11     
  12     def __init__(self, name):
  13         self._name = name
  14         setattr(self.__class__, name, self)
  15 
  16     def __str__(self):
  17         return '#%s' % str(self._name)
  18 
  19     def __repr__(self):
  20         return "%s('%s')" % (self.__class__.__name__, self._name)
  21 
  22     def getEnumerationSet(cls):
  23         result = sets.Set()
  24         for attr in dir(cls):
  25             attr = getattr(cls, attr)
  26             if isinstance(attr, Enumeration):
  27                 result.add(attr)
  28         return result
  29     getEnumerationSet = classmethod(getEnumerationSet)

   1 class PrimaryColorKind(Enumeration):
   2     pass
   3 PrimaryColorKind('Rouge')
   4 PrimaryColorKind('Vert')
   5 PrimaryColorKind('Bleu')
   6 
   7 print str(PrimaryColorKind.Rouge), str(PrimaryColorKind.Vert), str(PrimaryColorKind.Bleu)
   8 print PrimaryColorKind.getEnumerationSet()
   9 
  10 class ColorKind(PrimaryColorKind):
  11     pass
  12 ColorKind('Violet')
  13 
  14 
  15 print str(ColorKind.Rouge), str(ColorKind.Violet)
  16 print ColorKind.getEnumerationSet()
  17 print repr(ColorKind.Rouge), repr(ColorKind.Violet)
  18 assert(ColorKind.Rouge is ColorKind('Rouge'))