The Nature of Self

object N: Nat, object I: INT

• Self is a "recursive variable"
  • rec-var N: record
       var NUM: newint;
       proc SUCC = N.NUM := @N.NUM+1;
       proc PLUSTWO =
          call N.SUCC; call N.SUCC
    end
  • rec-var I: record
       var NUM: newint;
       proc PLUSTWO =
          call I.SUCC; call I.SUCC
       var ISNEG: newbool
       proc SUCC =
          if not I.ISNEG then ...
          else ...; fi
    end
• self is resolved to N respectively I!