this post was submitted on 14 May 2024
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Programmer Humor

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Explanation: Python is a programming language. Numpy is a library for python that makes it possible to run large computations much faster than in native python. In order to make that possible, it needs to keep its own set of data types that are different from python's native datatypes, which means you now have two different bool types and two different sets of True and False. Lovely.

Mypy is a type checker for python (python supports static typing, but doesn't actually enforce it). Mypy treats numpy's bool_ and python's native bool as incompatible types, leading to the asinine error message above. Mypy is "technically" correct, since they are two completely different classes. But in practice, there is little functional difference between bool and bool_. So you have to do dumb workarounds like declaring every bool values as bool | np.bool_ or casting bool_ down to bool. Ugh. Both numpy and mypy declared this issue a WONTFIX. Lovely.

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[–] breadsmasher 18 points 7 months ago* (last edited 7 months ago) (1 children)

This explanation is pretty clear cut

What exactly is your use case for treating np.bool_ and bool as interchangeable? If np.bool_ isn't a subclass of bool according to Python itself, then allowing one to be used where the other is expected just seems like it would prevent mypy from noticing bugs that might arise from code that expects a bool but gets an np.bool_ (or vice versa), and can only handle one of those correctly.

mpy and numpy are opensource. You could always implement the fix you need yourself ?

[–] [email protected] 1 points 7 months ago (1 children)

They've declared it as WONTFIX, so unless you're suggesting that OP creates a fork of numpy, that's not going to work.

[–] breadsmasher 2 points 7 months ago* (last edited 7 months ago) (2 children)

Well, yes exactly

  1. Create fixes
  2. Request merge. assume denied
  3. Fork numpy and add your changes there
  4. after just continue to pull new changes over from source of the fork and deal with any merge issues with the fix
[–] [email protected] 11 points 7 months ago (1 children)

Fork numpy

I have a feeling that you're grossly underestimating the magnitude of this endeavour

[–] breadsmasher 2 points 7 months ago

Im making no estimation one way or the other

[–] fubbernuckin 8 points 7 months ago (1 children)

That's incredibly inconvenient.

[–] breadsmasher 0 points 7 months ago

Thats what adding strong typing does for you