Module Util.Union

val map : ( 'a -> 'c ) -> ( 'b -> 'd ) -> ( 'a, 'b ) union -> ( 'c, 'd ) union
val equal : ( 'a -> 'a -> bool ) -> ( 'b -> 'b -> bool ) -> ( 'a, 'b ) union -> ( 'a, 'b ) union -> bool
val fold_left : ( 'c -> 'a -> 'c ) -> ( 'c -> 'b -> 'c ) -> 'c -> ( 'a, 'b ) union -> 'c