types
  MyInt = int [0..42] ;
  MyTuple = (MyInt, MyInt) ;
  TupleDemo = autocons system
  |[
  var
	theTuple : MyTuple = MyTuple(1,1) 
  actions
	ctr change1 = requires theTuple = MyTuple(1,1) :
		theTuple := MyTuple(1,2) 
		end ; 
        ctr change2 = requires theTuple[1] = 2 :
		theTuple := MyTuple(1,3)
                end 
  do
        change1 [] change2 
  od
  ]|
system
	TupleDemo