8:25:10beachThis page says ALIST is an association list. And the glossary says that an association list is a list of conses.
8:25:38beachPresumably, that implies that an association list is a proper list.
8:26:09beachBut look at the "Notes:" (yes, I know the notes are not part of the standard)...
8:27:01beachIt gives two almost equivalent expressions, but they are equivalent only if NIL is a member of the association list. But then, it is not an association list, now is it?
8:28:32beachIf I were to implement ASSOC, I would take the wording in the "Exceptional situations:" section to mean that if I detect that I don't have a proper list, or if I detect that an element is not a CONS cell, then I would signal an error.
8:29:08beachAnd that I don't have to search beyond a matching element to find out whether it is really an association list.