$ clisp

<...snip...>

[1]> (load "quarto.l")
;; Loading file quarto.l ...
;;  Loading file lp.l ...
;;  Loaded file lp.l
;; Loaded file quarto.l
T
[2]> (task53--uniform-style-p-demo)
((B+) [B+] [b+] (R+)) is uniform in style? T
((r-) [b-] [R-] (r-)) is uniform in style? T
((B-) [R+] [r+] (R-)) is uniform in style? NIL
NIL
[3]> (bye)
Bye.