lisp - Allegro CL, Debugging functions step by step -

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• how debug in [clozure] common lisp? 3 answers

i trying understand how function works in lisp, used allegro cl quite time ago, , remember had special function in repl, let see how function worked step step, in matlab. example, if had function:

(+ 1    (* 2 3       (/ 6 2)     )  ) 

you see each function step step, like:

(+ 1    (* 2 3       3) ) 

and then:

(+ 1    18) 

and finally:

19 

many in advance.

thanks jkiiski,

the code showing step step function be:

(step (+ 1 (* 2 3 (/ 6 2)))) 

and shows in detail how lisp parses data , evaluates function.

after many steps gives:

[step] cg-user(2):     result 6: 2   6: (/ 6 2) [step] cg-user(2):      result 5: 18    result 4: 18   result 3: 18  result 2: 18 2: (+ 1 18) [step] cg-user(2):   result 2: 19 result 1: 19