NumPy type hint that something is both an array and float32?

Question

How can I type hint that a value being returned by a function is both an NumPy array and holds NumPy float32 data?

I can specify that the returned value is an array using:

def func() -> np.ndarray:
    ...

However, this does not enforce the knowledge that it is a float32 array.

I can specify that the returned value is of type float32 using:

def func() -> np.float32:
    ...

However, this does not enforce the knowledge that it is an array (as opposed to a singular scalar value).

Is there a way I can get both specified in the return type?

@Georgy, I agree that it's close enough. I apologize for not finding that question originally. — Shiania White, Sep 21 '19 at 22:52

score 1 · Accepted Answer · answered Sep 21 '19 at 15:36

1

This is currently impossible but is a popular feature request; see this GitHub issue which contains information on progress and possible workarounds.

answered Sep 21 '19 at 15:36

fuglede

1 Answers1