box mybox(3)
class instance 1 created from scratch
  constructed with argument 3
		mybox = 4
class instance 2 created from scratch
  constructed with argument 4
class instance 1 assigned from instance 2
destroyed class instance 2
		mybox = foo(mybox + (boxcast)1)
class instance 3 created from scratch
  constructed with argument 1
entered function operator+(box&, box&)
  adding instances 1 and 3
    converting class instance 1 to integer (value 4)
    converting class instance 3 to integer (value 1)
  class instance 4 created from scratch
    constructed with argument 5
leaving function operator+(box&, box&)
entered function foo
		box bbox
  class instance 5 created from scratch
    default constructor
		bbox = abox + (boxcast)1
  class instance 6 created from scratch
    constructed with argument 1
  entered function operator+(box&, box&)
    adding instances 4 and 6
      converting class instance 4 to integer (value 5)
      converting class instance 6 to integer (value 1)
    class instance 7 created from scratch
      constructed with argument 6
  leaving function operator+(box&, box&)
  class instance 5 assigned from instance 7
  destroyed class instance 7
  destroyed class instance 6
		return bbox
    converting class instance 5 to integer (value 6)
  destroyed class instance 5
leaving function foo
destroyed class instance 4
class instance 8 created from scratch
  constructed with argument 6
class instance 1 assigned from instance 8
destroyed class instance 8
destroyed class instance 3
		return 0
destroyed class instance 1