3 ms·

what would you say are the limitations of Python type annotations? From the pycon demos I've seen it seems pretty functional and complete.

• deathanatos 9y ago
  * pylint / pep8 doesn't parse comment-based annotations, and thus flags imports that are in use as "unused" * numbers.Real / Union[float,int] do not work correctly; I basically can't figure a way to annotate a function that takes an int/float/decimal/etc. (mypy doesn't think "int" is a valid "Real", and it doesn't think you can add two Union[float,int] objects.) (mypy has nonetheless been very helpful, and overall I would recommend it.)
  • slaymaker1907 9y ago
    You don't need comment based annotations since there are real annotations since python 3.5
    • deathanatos 9y ago
      While true, my codebase regrettably needs to run in Python 2.7.
    • make3 9y ago
      I can't tell if you're neglecting the fact that most production Python is Python 2 on purpose or not
  • yorwba 9y ago
    > I basically can't figure a way to annotate a function that takes an int/float/decimal/etc. It seems like you should be able to just annotate it with float? ... when an argument is annotated as having type float , an argument of type int is acceptable ... https://www.python.org/dev/peps/pep-0484/#the-numeric-tower https://www.python.org/dev/peps/pep-0484/#the-numeric-tower
    • deathanatos 9y ago
      Hmm. I wasn't aware of that; still, it seems to not work for Decimal objects.