Extend the handling of field names in Fig. 6.18 to classes and single-inheritance class hierarchies. a) Give an implementation of class Env that allows linked symbol tables, so that a subclass can...

Extend the handling of field names in Fig. 6.18 to classes and single-inheritance class hierarchies.


a) Give an implementation of class Env that allows linked symbol tables, so that a subclass can either redefine a field name or refer directly to a field name in a superclass.

b) Give a translation scheme that allocates a contiguous data area for the fields in a class, including inherited fields. Inherited fields must maintain the relative addresses they were assigned in the layout for the superclass.

Fig. 6.18