;;CONTRACT tuple
FUNCTION make_0tuple():{tuple, []}
  TUPLE   0
  RETURN

FUNCTION make_2tuple(integer, integer):{tuple, [integer, integer]}
  PUSH       arg0
  PUSH       arg1
  TUPLE         2
  RETURN

FUNCTION make_5tuple(integer, integer, integer, integer, integer):
                {tuple, [integer, integer, integer, integer, integer]}
  PUSH       arg0
  PUSH       arg1
  PUSH       arg2
  PUSH       arg3
  PUSH       arg4
  TUPLE         5
  RETURN
  
FUNCTION element1(integer, integer): integer
  PUSH            arg0
  PUSH            arg1
  TUPLE              2
  ELEMENT integer    a 1 a
  RETURN

FUNCTION element({tuple, [integer, integer]}, integer): integer
  ELEMENT integer a arg1 arg0
  RETURN