Advertised and Unadvertised RA-Stack Operations

• Advertised RA-stack operations: those made available (public) to any code that wants to use RA-stacks, for example the arithmetic evaluation code.

• Unadvertised RA-stack operations: those made for the convenience of the implementor only.

To get at the actual stack vector, we will use:

     (define cells
       (lambda (ra-stack)
	 (vector-ref ra-stack 1)))

A: