Naive T Design Questions Addendum

[James J. Hunt <jjh@ll-vlsi.arpa>]

1. Oops!  #T should read #F.

6. Sorry, the form given in the last message:
   (define (read-keyword port ch rt)
     (let ((keyword (read-atom port rt ch)))
       (*lset (the-environment) keyword keyword)))
   is brain dead.  The second keyword in the *lset needs to be
   (list quote keyword), but this doesn't work either since
   (the-environment) is evaluated at the wrong time!  I don't know how to
   get the correct environment for this, the one into which the keyword is
   being read.  Quoting doesn't work because it is not known at read time if
   the keyword will be evaluated later:
	':key
	'(some list with :key embedded)
	`(some list with ,(read-port-with-different-read-table) embedded and
	  file contains :key)
	etc.

7. Why not separate the concept of () and no entry in tables?  This would be
   easy to implement since () valued keys could be left in place.  Then keys
   not present would denote empty key values.  The function TABLE-ENTRY
   should still probably return () for both.  Two new function would be
   needed: TABLE-ENTRY? for existence, and REMOVE-TABLE-ENTRY for removing a
   key from the table.  Note that having both #F and () doen't get one out
   of this mess, because one could imagine storing a false for the value of
   one key and an empty list for the value of another.  The user could map
   both back into say () but that would really violate the notion of there
   separation (not to mention what this may later break)!

	Thanks in advance,
				JJHunt

P.S.  The IF THEN ELSE macro would be more efficient if (= 1 (length rest)),
      is replaced by (not (cdr rest)).