In This Book

 

Figure 7-3. Sample Call/Return Stack and Program

There are three ways to refer explicitly to symbols using a frame block

quali￿er:

 

main relative

The notation is `main( n) where n is the number

 

of the frame counting from the least recent frame

of the call/return stack to the desired frame.

7

 

In the example in Figure 7-3, the frame with

 

print_answer is `main(5) . `main by itself refers

 

to the oldest frame in the stack. This frame may

 

not refer to your main program because in some

 

cases a procedure in a run-time library ma y be at

 

the base of your stack.

 

Identifying Program Objects 7-11