Empty polymorphic variant type?

[orbitz]

https://ocaml.org/manual/emptyvariants.html

Empty polymorphic variant type use case

Hello. I was wondering with some of my colleagues what the use case could be for an empty polymorphic variant type, apart from making some type that is empty at first but meant to be extended afterwards in other modules. type empty = | Second question: the previous declaration typechecks, but why can one match on a value in this empty type, if the compiler knows there are no constructors available? let f : empty -> bool = fun x -> match x with _ -> true (* should not typecheck? *) I am mai…