🚀 go-pugleaf

Jeff Berger writes:

> The June issue of AI Expert contains an article titled "Frames in
> CLOS", by J. Veitch. One of the topics covered is how to define CLOS
> classes so that slot values for CLOS instances can be retrieved from a
> data base as needed rather than being actually present in memory.
> That's close enough to a problem I'm trying to solve that I thought I
> could easily adapt the code to my purposes.

  [ ... code examples elided ... ]

> According to the article, making the allocation of the LIMIT slot an
> option unknown to CLOS (i.e., :ASSUMPTION) will suppress slot allocation.
> Unfortunately, when I attempt to create an instance of the class
> ORGANTOLERANCE, I get an error.

Your code has exposed a bug in the CLOS MOP in ACL 4.0.

The slot 'limit' in class ORGAN-TOLERANCE has indeed had its'
allocation suppressed.  Now when 'make-instance' gets called,
'shared-initialize' gets invoked (as your backtrace shows) and this is
where the bug is.  'shared-initialize' has a bug which assumes all
slots are allocated.  I will be sending you a patch direct under
separate cover.  This problem is fixed in the upcoming summer release
of ACL 4.1.

Please let me know if this fixes your problem.  Also feel free to
write direct to bugs@franz.com for support of this nature; if you are
paying for it you should use it!