List.filter
(fun name->
not ( List.exists (fun (name',_) -> name = Id name') params
|| List.exists (fun (name',_,_) -> name = Id name') fields)
) dom
List.filter
(fun name->
not ( List.exists (fun (name',_) -> name = Id name') params
|| List.exists (fun (name',_,_) -> name = Id name') fields)
) dom