What’s your hoster?

python -m http.server came in handy so many times!

Yes, that’s a good alternative for Collection[str] but not so much for Iterable[str] as you lose the lazyness of Generators.

Maybe something like passing in a list of patterns which should match some data, or a list of files/urls to download would be examples of where I would like to be generic, but taking in a string would be bad.

But the real solution be to convert it to foo(*args: str). But maybe if you take 2 Container[str] as input so you can’t use *args. But no real world example comes to mind.

Yes, you’re right. It also a lot of benefits.

This + an assert seems like the way to go. I think that str should never have fulfilled these contracts in the first place and should have a .chars property that returns a list of one-character-strings. But this change would break existing code, so it is not going to happen.

str matches most of these contracts, though, requiring additional checks if a str was passed or one of these collections containing strings.

But what if you actually don’t want str to be valid?

I know that Iterable and Collection aren’t the same. My point is, that if you use Iterable[str] or Collection[str] as a more flexible alternative to list[str] you no longer have any type-hinting support protecting against passing in a plain string and you could end up with a subtle bug by unexpectedly looping over ['f', 'o', 'o'] instead of ['foo'].

🦆