I'm currently trying to split functions matching against given variant
type and I'm running across this pb:

let a= function
 | `A -> ()
 | `B -> ()

doesn't split into

let c=function
 | `B -> ()

let b =function
 | `A -> ()
 |  x -> c x

since it messes up the type rules. I really want to avoid having to
write down precise type informations (The point here is to have an
extensible system)...

I am sure this question has been asked loads of times (but I couldn't
find the right thread in the archives) and I apologize for asking it
yet again.

Till