(* Fnlib.sig *) exception Impossible of string;val fatalError : string -> 'a; val getOption : 'a option -> 'a; val fst : 'a * 'b -> 'a;val snd : 'a * 'b -> 'b; val incr : int ref -> unit;val decr : int ref -> unit; val mapFrom:  (int -> 'a -> 'b) -> int -> 'a list -> 'b list;val map2:     ('a -> 'b -> 'c) -> 'a list -> 'b list -> 'c list;val appFrom:  (int -> 'a -> unit) -> int -> 'a list -> unit;val app2:     ('a -> 'b -> unit) -> 'a list -> 'b list -> unit;val revApp:     ('a -> unit) -> 'a list -> unit;val foldL:    ('a -> 'b -> 'b) -> 'b -> 'a list -> 'b;val foldL_zip : ('a -> 'b -> 'c -> 'c) -> 'c -> 'a list -> 'b list -> 'c;val foldL_map : ('a -> 'b -> 'b) -> ('c -> 'a) -> 'b -> 'c list -> 'b;val foldR:    ('a -> 'b -> 'b) -> 'b -> 'a list -> 'b;val foldR1:   ('a -> 'a -> 'a) -> 'a list -> 'a;val foldR_map: ('a -> 'b -> 'b) -> ('c -> 'a) -> 'b -> 'c list -> 'b;val map_fields : ('a -> 'b) -> ('c * 'a) list -> ('c * 'b) list;val all_fields : ('a -> bool) -> ('b * 'a) list -> bool;val exists_field : ('a -> bool) -> ('b * 'a) list -> bool;val app_field : ('a -> unit) -> ('b * 'a) list -> unit;val member : ''a -> ''a list -> boolval remove : ''a -> ''a list -> ''a listval drop : ('a -> bool) -> 'a list -> 'a list val lookup : ''a -> (''a * 'b) list -> 'b   (* May raise Subscript *)val binlookup  : string -> (string * 'b) Vector.vector -> 'b   (* Subscript *) val exists: ('a -> bool) -> 'a list -> bool val choose: ('a -> bool) -> 'a list -> 'a   (* May raise Subscript *)val find : ('a -> bool) -> ('a * 'b) list -> 'b   (* May raise Subscript *)val foldInt : (int -> 'b -> 'b) -> 'b -> int -> 'bval duplicates : ''a list -> bool;val stringToLower : string -> string; val for : (int -> unit) -> int -> int -> unit; val zip2 : 'a list -> 'b list -> ('a * 'b) list;