Re:Sshole
by forresthopkinsa on Thursday November 05, 2026 @03:07PM
(#50383789)
> But there has to be something in the payload field when it is not applicable
Not in languages with ergonomic sum types. A `Result` or `Either` will have no payload field on the error type. The compiler won't let you dereference it.
This is wrong. errno is not to be used to detect errors, only to get the cause of the error once an error has been detected.
Re:Sshole
by lemonwaterlime on Friday November 06, 2026 @10:12AM
(#50393300)
In Haskell, one would return a Maybe or an Either here.
Maybe
——————
Just hash
Nothing
For Either
————————————
Left err
Right hash
But there has to be something in the payload field when it is not applicable. A null is perfectly fine.
The argument for changing that to "", if I understand the above linked discussion correctly, was that some users of this api threw away errors and a dummy value would be harder to ignore. You could argue that these behaviours are less common in Rust or Go, but that's not a technical difference.
The world is not perfect and sometimes you really need to work around bad users. Even in Rust or Go. I am not convinced this was such a case. If you are convinced it was it would still have been better to select a less trivial dummy value (such as ":ERROR:*").