$ clisp

<...snip...>

[1]> (load "genetics-individual.l")
;; Loading file genetics-individual.l ...
;; Loaded file genetics-individual.l
T
[2]> (setf ind (make-individual '(h e l l o w o r l d) 4))
#<INDIVIDUAL #x106AE801>
[3]> (visualize-individual ind)
Individual 4:
(H E L L O W O R L D) (fitness: 0)
NIL
[4]> (setf (individual-fitness ind) (length (individual-data ind)))
10
[5]> (visualize-individual ind)
Individual 4:
(H E L L O W O R L D) (fitness: 10)
NIL
[6]> (setf (individual-data ind) '(h e l l o c s c 4 6 6))
(H E L L O C S C 4 6 6)
[7]> (setf (individual-fitness ind) (length (individual-data ind)))
11
[8]> (visualize-individual ind)
Individual 4:
(H E L L O C S C 4 6 6) (fitness: 11)
NIL
[9]> (bye)
Bye.