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Date: Thu, 1 Oct 92 09:13:30 EDT
From: Ashwin Ram <ashwin@cc.gatech.edu>
Message-Id: <9210011313.AA05548@leo.cc.gatech.edu>
To: Peter Shell <pshell@SALVADOR.MT.CS.CMU.EDU>
Cc: ashwin@cc.gatech.edu
In-Reply-To: Peter Shell's message <CMM.0.90.2.717903424.pshell@SALVADOR.MT.CS.CMU.EDU> of Wed, 30 Sep 92 21:37:04 EDT
Subject: Re: Followup to previous note
Reply-To: Ashwin Ram <ashwin@cc.gatech.edu>

It turns out that that patch is not sufficient.  If you MAKE-FRAME a new
instance of, say, PTRANS as DEF-FRAMEd in my previous message, and you
specify initial values of an inherited slot such as ACTOR, you get a similar
error (I think it is generated by CHECK-SLOT-ARGS) complaining that that slot
and facet pair does not exist in that frame.  Similarly, if you SET-FACET a
new value into an inherited slot, again you get a similar error (this time in
SET-FACET-DEMONS0).  So defining, making, accessing and setting would all
need to be fixed.

For the purposes of my class, I've decided to get around this problem by
modifying FIND-FRAME-SLOTS to return ALL-SPECS (i.e., to pretend that
CACHED-SLOTS was :*ALL*.  This way all inheritance is done at define time
rather than run time, but this is transparent to the students.  Of course,
this is not really a fix, just a temporary workaround.

Thanks.

-- Ashwin.

