SList.Skip
These iterators ignore the default values in the list.
val iter : ('a -> unit) -> 'a t -> unit
val map : ('a -> 'b) -> 'a t -> 'b t
val fold : ('a -> 'b -> 'a) -> 'a -> 'b t -> 'a
val for_all : ('a -> bool) -> 'a t -> bool
val exists : ('a -> bool) -> 'a t -> bool