anchor.diff:  
   target definitions
   
  -:: begin	*label dup label, ;;
  +:: begin	begin, ;;
   :: again	goto, ;;
   
   :: if		if, ;;
  
positive.code: \ need to provide accessors for the data and stacks.  >R R> and R@ are already
  \ familiar to the programmer.  However, we also introduce >D D> and D@ as
  \ well to provide similar access to the Forth data stack.
  
  host definitions
  
  : >r,		20 insn, ;
  : r>,		21 insn, ;
  : r@,		22 insn, ;
  : r!,		23 insn, ;
  : >d,		24 insn, ;
  : d>,		25 insn, ;
  : d@,		26 insn, ;
  : d!,		27 insn, ;
  
  : dup,		28 insn, ;
  : over,		29 insn, ;
  : drop,		30 insn, ;
  : nip,		31 insn, ;
  : rot,		32 insn, ;
  : swap,		33 insn, ;
  
  target definitions
  
  
negative.code: :: d@		d@, ;;
  :: d!		d!, ;;
  
  \ The normal Forth stack accessors that you're used to now apply only to the
  \ evaluation stack, NOT to the data stack.  (Sorry!)  Any other approach will
  \ just add too much runtime overhead and will not yield good runtime
  \ performance.
  
  host definitions
  
  : dup,		28 insn, ;
  : over,		29 insn, ;
  : drop,		30 insn, ;
  : nip,		31 insn, ;
  : rot,		32 insn, ;
  : swap,		33 insn, ;
  
  target definitions
  
  :: dup		dup, ;;
  :: over		over, ;;
  :: drop		drop, ;;
  