Here are a couple of minor points I came up with while reviewing
the document:

(1) Can we make empty enum types, i.e. should (make-enum-type '())
return a value?

(2) enum-set should take one or more arguments, since the empty enum
set has no determinable type.

(3) What is the rationale for including only the linear-update set
theoretical operations?  I'd like to have the non-! versions as well,
if possible.

Is there anything else, or are we ready for last call?

--
Wolfgang Corcoran-Mathe  <xxxxxx@sigwinch.xyz>

"The most important computer is the one that rages in our skulls
and ever seeks that satisfactory external emulator." --Alan J. Perlis