It is implicit that cons (e, l) ≠ l cons (e, l) ≠ e cons (e1, l1) = cons (e2, l2) if e1 = e2 and l1 = l2 Note that first (nil ()) and rest (nil ()) are not defined.
יוצא מכך ש: cons (e, l) ≠ l cons (e, l) ≠ e cons (e1, l1) = cons (e2, l2) if e1 = e2 and l1 = l2 שימו לב ש-first (nil ()) ו-rest (nil ()) אינם מוגדרים.