[Python-ideas] Optional Static Typing -- the Python Way

[Antoine Pitrou]

Le 21/08/2014 10:30, Brett Cannon a écrit :
>
> Isn't that the magic of __instancecheck__/__subclasscheck__? If
> typing.py does the right thing here then it shouldn't matter.

What is "the right thing"?

> You could
> use __init__ or __getitem__ to construct an object who upon
> introspection provides the details you want and do what you expect, and
> then override the appropriate methods so that isinstance() checks check
> against the ABC instead of the type class itself (heck we could make the
> base type class require that you inherit from an ABC to promote working
> with ABCs instead of concrete classes).

So we agree that type descriptions should be separate things from ABCs, 
or not?

> I have to also say that I like using ABCs because `from collections
> import abc as a` leads to reading parameters like "x is a.Mapping" which
> is linguistically quaint. =)

Except that "x is a.Mapping" is False with a normal Python.

Regards

Antoine.