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.

  • breadsmasher@lemmy.world
    link
    fedilink
    English
    arrow-up
    21
    arrow-down
    3
    ·
    edit-2
    6 months ago

    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 ?

    • Ephera
      link
      fedilink
      arrow-up
      4
      arrow-down
      3
      ·
      6 months ago

      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@lemmy.world
        link
        fedilink
        English
        arrow-up
        4
        arrow-down
        2
        ·
        edit-2
        6 months ago

        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