point 122

[Earl A. Killian <EAK at MIT-MC>]

Another possibility, instead of using MEMBER or ONEOF, is to
allow (QUOTE <A>) to be a legal type specifier that means exactly
the object <A>.  Exasmple 1: (MEMBER A B C) would be (OR 'A 'B 'C).
Example 2: type LIST could be defined as (OR CONS '()).