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Naive T Design Questions Addendum
Date: Thu, 14 Apr 88 21:59:49 EDT
From: James J. Hunt <jjh at ll-vlsi.arpa>
7. Why not separate the concept of () and no entry in tables?
(I think you mean #F, not (), since absence of entry is indicated by a
false return from table-entry.) This is easily simulated given the
existing primitives, so it would be an unnecessary complication. E.g.
it would require the addition of something like a TABLE-HAS-ENTRY?
predicate, and it would require the addition of a separate procedure for
deleting entries (currently you can just store a #F).
P.S. The IF THEN ELSE macro would be more efficient if
(= 1 (length rest)), is replaced by (not (cdr rest)).
You are dealing with lists, not booleans, so I think you want NULL?, not