type ('a, 'b) or_ =
  	| Inl of 'a
  	| Inr of 'b;;

let f1 x = match snd x with
    |Inl y -> Inl (fst x, y)
    | Inr z -> Inr (fst x, z);;

let f2 x = match x with
  	|Inl y -> (fst y, Inl (snd y))
  	|Inr z -> (fst z, Inr (snd z));;