Enum is not a type, like the OP suggested: from enum import Enum class Color(Enum): WHITE = 1 type(Color) <class 'enum.EnumMeta'> type(Enum) <class 'enum.EnumMeta'> type(enum.EnumMeta) <class 'type'> Enum.__len__ <bound method EnumMeta.__len__ of <enum 'Enum'>> So to me it looks like Enum is just a generic, empty enum. The __len__ method is implemented in EnumMeta. Op 3/04/2023 om 00:18 schreef Greg Ewing:
On 2/04/23 6:36 pm, Benedict Verhegghe wrote:
An Enum is functionally a container with a limited set of constants. Why should it not be legitimate to ask for the number of constants in it?
But Enum itself isn't an enum, it's a constructor for enums. I think len() just happens to work on it as a side effect of the way enums are implemented.