
  [;1m-spec set(Terms, Type) -> Set[0m
  [;1m             when Set :: a_set(), Terms :: [term()], Type :: type().[0m

  Creates an unordered set. [;;4mset(L, T)[0m is equivalent to [;;4m[0m
  [;;4mfrom_term(L, T)[0m, if the result is an unordered set. If no type
  is explicitly specified, [;;4m[atom][0m is used as the set type.
