I think this code makes some sort of argument in the debate about whether Python has too much flexibility or if it's the best metaprogramming toolset in the world. I'm not sure which side of the debate it falls on, though.
class Building: resource = None @classmethod def __init_subclass__(bldg): super().__init_subclass__() print("Building:", bldg.__name__) def make_recipe(recip): print(recip.__name__.replace("_", " "), "is made in a", bldg.__name__.replace("_", " ")) bldg.__init_subclass__ = classmethod(make_recipe) class Extractor(Building): ... class Refinery(Building): ... class Crude(Extractor): resource = "Oil" time: 1 Crude: 1 class Plastic(Refinery): Crude: 3 time: 6 Residue: 1 Plastic: 2 class Rubber(Refinery): Crude: 3 time: 6 Residue: 2 Rubber: 2 Full code is here if you want context: https://github.com/Rosuav/shed/blob/master/satisfactory-production.py Subclassing Building defines a class that is a building. (The ellipsis body is a placeholder; I haven't implemented stuff where the buildings know about their power consumptions and such. Eventually they'll have other attributes.) But subclassing a building defines a recipe that is produced in that building. Markers placed before the "time" are ingredients, those after the "time" are products. There are actually a lot of interesting wrinkles to trying to replace __init_subclass__ on the fly. Things get quite entertaining if you don't use the decorator, or if you define and decorate the function outside of the class, or various other combinations. On a scale of 1 to "submit this to The Daily WTF immediately", how bad is this code? :) ChrisA -- https://mail.python.org/mailman/listinfo/python-list