src/mdis/core.py

   1 class TypeidHook(object):
   2     def __init__(self, *typeids):
   3         for typeid in typeids:
   4             if not isinstance(typeid, type):
   5                 raise ValueError(typeid)
   6         self.__typeids = typeids
   7         return super().__init__()
   8
   9     def __iter__(self):
  10         yield from self.__typeids
  11
  12     def __repr__(self):
  13         return f"{self.__class__.__name__}({self.__typeids!r})"
  14
  15     def __call__(self, call):
  16         if not callable(call):
  17             raise ValueError(call)
  18         return CallHook(typeids=self, call=call)
  19
  20
  21 class CallHook(object):
  22     def __init__(self, typeids, call):
  23         if not isinstance(typeids, TypeidHook):
  24             raise ValueError(typeids)
  25         if not callable(call):
  26             raise ValueError(call)
  27         self.__typeids = typeids
  28         self.__call = call
  29         return super().__init__()
  30
  31     def __iter__(self):
  32         yield from self.__typeids
  33
  34     def __repr__(self):
  35         return f"{self.__class__.__name__}(call={self.__call!r}, typeids={self.__typeids!r})"
  36
  37     def __call__(self, dispatcher, instance):
  38         return self.__call(dispatcher, instance)
  39
  40
  41 def hook(*typeids):
  42     return TypeidHook(*typeids)