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.

  • Semperverus@lemmy.worldEnglish
    31·
    8 months ago

    The JS thing makes perfect sense though,

    “1” is a string. You declared its type by using quotes. myString = "1" in a dynamically typed language is identical to writing string myString = "1" in a statically typed language. You declare it in the symbols used to write it instead of having to manually write out string every single time.

    2 is an integer. You know this because you used neither quotes nor a decimal place surrounding it. This is also explicit.

    "1" + 2, if your interpreter is working correctly, should do the following

    • identify the operands from left to right, including their types.

    • note that the very first operand in the list is a string type as you explicitly declared it as such by putting it in quotes.

    • cast the following operands to string if they are not already.

    • use the string addition method to add operands together (in this case, this means concatenation).

    In the example you provided, "1" + 2 is equivalent to "1" + "2", but you’re making the interpreter do more work.

    QED: "1" + 2 should, in fact, === "12", and your lack of ability to handle a language where you declare types by symbols rather than spending extra effort writing the type out as a full english word is your own shortcoming. Learn to declare and handle types in dynamic languages better, don’t blame your own misgivings on the language.

    Signed, a software engineer.

    • lwuy9v5@lemmy.world
      2·
      8 months ago

      TypeError is also a correct response, though, and I think many folks would say makes more sense. Is an unnecessary footgun