Getting values from a list of length-2 lists

Question

There is a defconstant statement:

(defconstant *contant2* '((Allan 4) (Zols 5) (Milo 2) (Judh 0)))

I want to take separated from this constant the name and the value associated with the name. How can I do that?

I need to achieve this goal:

Give taste scores: ((name-1 score-1) ... (name-n score-n)) as an argument, LISP functions which avare score and other which generate word scores (9-10 is VeryGood, 7-8 is Good).

I appreciate any help! Thanks.

Answer 1

To answer your direct question:

? (mapcar #'car *cookie-scores*)
(JOHN MARY MIKE JANE)
? (mapcar #'cadr *cookie-scores*)
(8 9 1 0)

In a loop, you can use loop's destructuring:

for (name val) in

Other options are available; here's 2 example implementations of the required functions that I will leave uncommented; please ask questions, or show us your code.

(defun average-score (lst)
  (/ (reduce #'+ lst :key #'cadr) (length lst))))

? (average-score *cookie-scores*)
9/2

and

(defun word-scores (lst)
  (loop 
    for (name val) in lst
    collect (list name
                  (cond
                   ((> val 8) 'Excellent)
                   ((> val 6) 'Tasty)
                   ((> val 0) 'Terrible)
                   (t         'Garbage)))))

? (word-scores *cookie-scores*)
((JOHN TASTY) (MARY EXCELLENT) (MIKE TERRIBLE) (JANE GARBAGE))