If you spend your life talking about bool having two values, and then need to act as if it has three or 256 values or whatever, that's where the weirdness lives.
replyIn C, true doesn't necessarily equal true.
In Java (myBool != TRUE) does not imply that (myBool == FALSE).
Maybe you could do with some weirdness!
In Haskell: Bool has two members: True & False. (If it's True, it's True. If it's not True, it's False). Unit has one members: () Void has zero members.
To be fair I'm not sure why Void was raised as an example in the article, and I've never used it. I didn't turn up any useful-looking implementations on hoogle[1] either.
[1] https://hoogle.haskell.org/?hoogle=a+-%3E+Void&scope=set%3As...
What were you expecting to find? A function which returns an empty type will always diverge - ie there is no return of control, because that return would have a value that we've said never exists. In a systems language like Rust there are functions like this for example std::process::exit is a function which... well, hopefully it's obvious why that doesn't return. You could imagine that likewise if one day the Linux kernel's reboot routine was Rust, that too would never return.
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