CLEAR
x = CREATEOBJECT("c1")
x.o = .NULL.  && Does nothing
x = .NULL.   && Fires C1.Destroy() but it's still there
? "RELEASE THE CLASS FROM MEMORY"
CLEAR CLASS c1 && this relase the class memory image


DEFINE CLASS c1 AS CUSTOM
  o = CREATEOBJECT("c2") && this put a c2 reference into the C1 class MEMORY image
  PROCEDURE DESTROY()
    ? "C1 Destroy"
  ENDPROC
ENDDEFINE

DEFINE CLASS c2 AS CUSTOM
  PROCEDURE INIT()
    ? "C2 Init"
  ENDPROC
  PROCEDURE DESTROY()
    ? "C2 Destroy"
  ENDPROC
ENDDEFINE