Python’s “type hints” are a bit of a disappointment to me
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Python’s “type hints” are a bit of a disappointment to me
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Re: Python’s “type hints” are a bit of a disappointment to me
#2I haven't used python's type hints much yet but I used TypeScript a bunch about a year ago and I have the exact same complaints.
Most of the benefit of types goes away unless _everything_ is typed... my libraries, the libraries my libraries use, etc. I should be able to jump around in and out of library code following types and usages thereof in my IDE, making conclusions that are accurate based on what the types say.
When some of your libraries (or indirect dependencies) don't have types, you can no longer ever make any firm conclusions when exploring a complex codebase based on types. I want to change a method in the Widget type, and my IDE says it's used in 4 places. But in reality, that just means 4 or more places, who knows if there are others.
Adding types to a language that doesn't already have them is very hard for this reason. Until many years pass and they're in universal use, they add little value.
Re: Python’s “type hints” are a bit of a disappointment to me
#3[deleted]
Re: Python’s “type hints” are a bit of a disappointment to me
#4It reminds me of this 5 year old bug in mypy: "int is not a Number?" [1].
Re: Python’s “type hints” are a bit of a disappointment to me
#5I use the type-annotated python at work and at hobby.
I see the point of OP, but I'd say it helps even if it's not perfect or "sound".
Though I agree on its negative impact on the language ergonomics. It removes the joy of writing "scripting language" and as a statically typed language it is far from static-type-native ones.
Now I see it as a tax for compatibility: You enjoy dynamic typing at the beginning of the project, but you have to pay it back once you've grown up to a certain scale.
TypeScript to me feels much more like a native static typed language because it is. Does it help to be a transpiler? Maybe. But I would think that Hejlsberg just has done an astonishingly good work to make it compelling. Python's type annotation is good and completely reasonable, but gradual typing is such a hard problem and being good is probably not enough here.
Re: Python’s “type hints” are a bit of a disappointment to me
#6I love type hints. They make the code so much more readable. I wish they could do more, but knowing what the programmer intended for a variable is huge. Now, when I see code without type hints I think, "Oh man, now I have to dig into everything to know what anything is."
Re: Python’s “type hints” are a bit of a disappointment to me
#7100% agree - never really understood the movement behind adding types to Python. Type hints are a useless complexity that yield little return. If you want types, use something else other than Python. The whole thesis behind Python is simple is better than complex.
Re: Python’s “type hints” are a bit of a disappointment to me
#8I tried mypy when I first started into type checking in Python back when I was trying to do Python in VS Code and I discovered that mypy is a time-sucking anti-productivity disaster that needs to die in a fire.
When I started learning PyCharm though, I discovered that type checking can actually work well in Python and it is not a waste of time at all. So I advise people now that unless you're using PyCharm, do not waste any time on type checking Python. In which case, have at it. I love it. PyCharm is really the only way to do type-checking productively right now.
Re: Python’s “type hints” are a bit of a disappointment to me
#9I agree treating Type Hints as comments is the way to go. It's a bit nicer to use a library that is fully-hinted than one that is not. But I don't worry about type-hinting my own code, unless it's a particular complicated function signature that other people will be calling.
Re: Python’s “type hints” are a bit of a disappointment to me
#10Only facts here. I think most large codebases eventually see type hints drift away from reality as individual contributors are more incentivized to hack in `Any` types to make things compile instead of typing every line properly. This is especially common for handling data objects which come in over the network - often they can have a couple different types but people just type it as one thing for simplicity.
Overall I do think type hints are worth it though, for maybe two benefits. They force you to look at the ridiculous types you are using, like `List[Union[None, str, List[Dict[str, str]]]]` which is the sort of thing that happens in codebases all the time. It adds just enough friction to push people to make explicit dataclasses or simplify function returns, which is good. Secondly they help with tracking functions which return None, which is a pain when following callstacks in big codebases.