CS135 Trace

Path

You could find the cs135-trace.rkt here:

~/web/content/assign/dr_racket/cs135-trace.rkt

How to use it

We use it for debugging (this is helpful in office hour)

1. Change the racket file you want to trace into full racket version. Go to Language -> Choose Language -> Choose The Racket Language
2. Put the cs135-trace.rkt into the same directory with the file you want to trace
3. Add (require "trace.rkt") on the top of the file be traced
4. Change the function define/trace for example
   • 
5. write an expression: for example: (f 5)
6. click run, and then you could see the each step of the function in the interaction window, e.g. how does the function execute

>(f 5)
> (f 4)
> >(f 3)
> > (f 2)
> > >(f 1)
> > > (f 0)
< < < '()< < <'(1)< < '(2 1)< <'(3 2 1)< '(4 3 2 1)<'(5 4 3 2 1)(list 5 4 3 2 1)

the > means deeper level of the stack

-- Ariel L - 2020-12-23

• Example function for tracing: