[Numpy-discussion] [Python-3000] PEP 31XX: A Type Hierarchy for Numbers (and other algebraic entities)

[Bill Janssen]

GvR wrote:
> So how about we reduce the scope of our (!) PEP (or perhaps of a new
> one) to two items: (a) add @abstractmethod, and (b) overload
> isinstance() and issubclass()? Library authors can do everything they
> want with those, and we can always add a specific set of ABCs for
> containers and/or numbers later in the 3.0 development cycle.

-1.  Adding mechanism without content seems less than ideal, despite
Talin's misgivings.  I'd recommend adding the base classes in, and see
how they work in the earliest 3.0 releases, then modify them as
necessary in subsequent releases.

Bill