Re: TUPLE

On Feb 1, 2:04 pm, toto <stop-aux-sp...@[EMAIL PROTECTED]
> wrote:
> ECMA allows to declare
>
>         x: TUPLE[count, balance: INTEGER; name, forname: STRING]
>
> My question is: "how useful is it?".
>
> regards

Very useful for setting up lookup tables. Consider this sketch of an
enumeration (stream of consciousness code that's badly formatted and
untested, to get to the point):

class MONTH create make

feature make (a_id: INTEGER) is do id := a_id end

  id: INTEGER

  name: STRING is do Result := table[id].name end

  long_name: STRING is do
    Result := table[id].long_name
    if Result = Void then
      Result := name
    end
  end

feature {NONE} -- Implementation (the point)

  table: TUPLE[id: INTEGER; name, long_name: STRING] is once
    Result := <<
       [ 1, "Jan", "January" ],
       [ 2, "Feb", "February" ],

           -- and so one
    >>
  end

invariant

  valid_id: id >= 1 and then id <= table.count

end