On Sat, Nov 25, 2017 at 3:09 PM, Juan Nunez-Iglesias
This is a complete outsider’s perspective but
(a) it would be good if NumPy type annotations could include an “array_like” type that allows lists, tuples, etc.
I'm sure this will exist.
(b) I’ve always thought (since PEP561) that it would be cool for type annotations to replace compiler type annotations for e.g. Cython and Numba. Is this in the realm of possibility for the future?
It turns out that the PEP 484 type system is *mostly* not useful for this. They're really designed for checking consistency across a large code-base, not for enabling compiler speedups. For example, if you annotate something as an int, that means "this object is a subclass of int". This is enough to let mypy catch your mistake if you accidentally pass in a float instead, but it's not enough to tell you anything at all about the object's behavior -- you could make a wacky int subclass that acts like a string or something. Probably there are some benefits that compilers can get from PEP 484 annotations, but you should think of them as largely an orthogonal thing. -n -- Nathaniel J. Smith -- https://vorpus.org