module Person = struct
  type name_t = string
  type address_t = string
  type t = { name: name_t; addresses: address_t list }
  let empty = { name = ""; addresses = [] }
  let compare = Stdlib.compare
  let name_to_string p = p.name
  let to_string p = List.fold_left (fun a e -> Printf.sprintf "%s <%s>" a e) p.name p.addresses
  let of_string s = match String.trim s with "" -> empty | s ->
    match Str.(split (regexp " *< *") s) with
    | [] -> empty
    | [n] -> let name = String.trim n in { empty with name }
    | n::adds ->
      let name = String.trim n in
      let addresses = List.map (fun f -> String.(sub f 0 (length f -1))) adds in
      { name; addresses }
end

include Person

module Set = struct
  include Set.Make(Person)
  let to_string ?(names_only=false) ?(pre="") ?(sep=", ") s =
    let str = if names_only then Person.name_to_string else Person.to_string in
    let j x a = match a, x with "",_ -> str x | _,x when x = Person.empty -> a | _ -> a^sep^str x in
    fold j s pre
  let of_string s = of_list (List.map Person.of_string (String_set.list_of_csv s))

  let of_stringset s = String_set.fold (fun e a -> union (of_string e) a) s empty
  let of_query q = of_stringset (fst q), of_stringset (snd q)
  let predicate (inc, exl) set = not (disjoint inc set) && disjoint exl set
end