MapExtra.List
Map whose images are lists of elements
val add : key -> 'a -> 'a list t -> 'a list t
Add element to the list at key, create list if non-existent
val mem : key -> 'a -> 'a list t -> bool
val find : key -> 'a list t -> 'a list
empty list if not present
val fold : (key -> 'a -> 'b -> 'b) -> 'a list t -> 'b -> 'b
val iter : (key -> 'a -> unit) -> 'a list t -> unit
val mapi : (key -> 'a -> 'b) -> 'a list t -> 'b list t
val map : ('a -> 'b) -> 'a list t -> 'b list t
val filter : (key -> 'a -> bool) -> 'a list t -> 'a list t
val mapi_bind : (key -> 'a -> 'b list) -> 'a list t -> 'b list t
val map_bind : ('a -> 'b list) -> 'a list t -> 'b list t
val mapi_filter : (key -> 'a -> 'b option) -> 'a list t -> 'b list t
val map_filter : ('a -> 'b option) -> 'a list t -> 'b list t