functor HASHDICT( structure D:DictSig 
                  val hash: D.Key -> int  
                  val size:int) =
  struct local open Array in
    type Dict = D.Dict array
    val Lookup = D.Lookup
    fun empty () = array(size, D.empty)

    fun lookup d k = 
                   D.lookup (d sub (hash k)) k

    fun enter((k,e),d) = 
        let val h = hash k in
        update(d, h, D.enter((k, e), d sub h))
        end

    fun remove(k,d) =
        let val h = hash k in
        update(d, h, D.remove(k, d sub h))
        end
  end 
end;