The class's __init__
method has 3 arguments, but when I instantiate it with 3 arguments, it throw an error that it expected 1 arguments. I cannot undrestand.
class ArrObj(frozenset):
def __init__(self, elem_list, elem_count, self_count):
super(ArrObj, self).__init__(elem_list) # Enums, ArrObj, race_id
self.elem_count = elem_count
self.self_count = self_count
assert self_count > 0
if __name__ == '__main__':
a = ArrObj(['a', 'b', 'c'], {'a':1, 'b':2, 'c':3}, 8)
Traceback (most recent call last):
File "G:/pycharm-projects/new_keyinfo/verify_treekeys.py", line 34, in <module>
a = ArrObj(['a', 'b', 'c'], {'a':1, 'b':2, 'c':3}, 8)
TypeError: ArrObj expected at most 1 arguments, got 3
frozenset.__init__
doesn't take additional arguments, because you can't modify a frozenset
after it has been created. (In fact, frozenset
doesn't define __init__
at all; it just uses the __init__
it inherits from object
.) The iterable you pass to frozenset
is consumed by frozenset.__new__
instead.
class ArrObj(frozenset):
def __new__(cls, elem_list, elem_count, self_count):
# May as well assert this before you do any more work
assert self_count > 0
obj = super().__new__(cls, elem_list)
obj.elem_count = elem_count
obj.self_count = self_count
return obj