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Comment by fire_lake | Hacker News Reader

The Python ecosystem is not built around types.

For example, you will find functions where the runtime value of parameters will change the return type (e.g. you get a list of things instead of one thing). So unless we want to throw out huge amounts of Python libraries (and the libraries are absolutely the best thing Python has going for it) then we have to accept that it’s not a very good statically type language experience.

The JS community on the other hand had adopted TypeScript very widely. JS libraries are often designed with typing in mind, so despite being weakly typed, the static type experience is actually very good.

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I don't disagree. However, often, when I use a library, I use it within a small function that I control, which I can then type again. Of course, if libraries change e.g. the type they return over time (which they shouldn't also according to Rich), you often only notice if you have a test (which you should have anyway).

Moreover, for many libraries there are types- libraries that add types to their interface, and more and more libraries have types to begin with.

Anyway just wanted to share that for me at least it's in practice not so bad as you make it sound if you follow some good processes.

YMMV. I have over two decades of experience with Python and about a decade with JS though it's all backend work. I use both in my day job, but write in Python more frequently. I've found the transition to Python static typing much more seamless and easier to adopt than TS.

Amusingly, I can't call any time where I'd had to deal with differently typed return values in Python, but just recently had to fix some legacy JS code that was doing that (a function that was returning null, scalar, or array depending upon how many values it got in response to a SQL query).

$0.02.

>For example, you will find functions where the runtime value of parameters will change the return type (e.g. you get a list of things instead of one thing).

I have long argued that such interfaces are doing it wrong. That's what "Special cases aren't special enough to break the rules." in the Zen is supposed to warn about, to my understanding.

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