Re:Python, as Reviewed by a C++ Programmer
by striking on Sunday April 23, 2017 @01:38PM
(#14179230)
Sure, but most python code isn't annotated, right?
So this might be helpful for code you wrote, but not anywhere it interfaces with other peoples' code (which, in my opinion, is probably the most important place to check for type errors).
The older method is docstrings (reST and similar) like here: https://github.com/kennethreitz/requests/blob/master/request...
IDEs like PyCharm can use those and other methods to find most typing issues. In practice this is very effective for most "boring" Python code, but if you get really clever it falls over completely.
Re:Python, as Reviewed by a C++ Programmer
by humanfromearth on Sunday April 23, 2017 @02:06PM
(#14179430)
True, but very popular packages are usually battle tested and type errors are very rare in practice in those packages. Most bugs I've seen are not because of the lack of a static type system.
Plus, many packages dynamically add members, stomp named parameters by wrapping stuff with kwargs, etc.
Re:Python, as Reviewed by a C++ Programmer
by humanfromearth on Sunday April 23, 2017 @02:10PM
(#14179455)
So monkey patching is bad you're saying? I agree that it's possible what you're saying about kwargs, but after about 6 years of python I've never encountered that in any of the code that I've worked on.
Or specifically to his example,
from typing import Dict
Foo = Dict[int:str]
def __init__(self, name:str, balance=0.0):
"""Construct a Klass."""
self.myfoos = {} # type: Foo
It is possible to add annotations to your code like
and then run type checks using `mypy`, so that for the annotated code probability of the "passes the checks => won't crash the runtime" case is much larger.