tidy: Improve comment on np-special casing

[danra]

np.astype became available in numpy 2.1

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[danra]

Looks like this is failing due to dask not having implemented np.astype. Not familiar with dask. Shall I just close this, or should this be amended somehow to only use np.astype in the numpy, non-dask case?

[keewis]

it's not just that: we're still maintaining backwards compatibility with numpy<2 (see the bare-minimum CI), which means that we still need the special-casing for that, as well.

Either way, thanks for the PR. Unfortunately, I think this might not be the right time, yet.

Edit: but maybe you can repurpose the PR to make the comment more accurate? I.e. that this is for backwards-compat and dask?

[danra]

@keewis Done.
I still don't know why this is needed for dask - doesn't it use its own namespace? I've no experience with dask.
Perhaps you'd like to make that clearer in the comment and/or commit message (besides also telling me).

[keewis]

I think you force-pushed back to the original state (I think we need the changes from feb81db).

dask doesn't follow the array API (yet?), which explains the missing function

[danra]

Oops, sorry about that, pushed again.

[danra]

dask doesn't follow the array API (yet?), which explains the missing function

but I didn't get why it's under the condition if xp == np

[keewis]

Thanks! This looks good to me.

but I didn't get why it's under the condition if xp == np

dask doesn't implement __array_namespace__, so we're falling back to np to dispatch through __array_function__ and __array_ufunc__.

[danra]

dask doesn't implement array_namespace, so we're falling back to np to dispatch through array_function and array_ufunc.

Ah, I see. Thanks!