beowulf/resources/mexpr/efface.mexpr.lsp

6 lines
247 B
Common Lisp

;; page 63. I'm not at all sure why an implementation using RPLACD is preferred
;; over a pure functional implementation here.
efface[x; l] = [null[l] -> NIL;
equal[x; car[l]] -> cdr[l];
T -> rplacd[l; efface[x; cdr[l]]]]