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Date: Thu, 26 Jul 90 10:58:45 BST
From: tfm@uk.ac.cam.cl
Message-Id: <9007260958.AA04661@uk.ac.cam.cl.moorhen>
To: info-hol@clover.ucdavis.edu
Subject: all_sets library : revision and contributions
Sender: tfm@uk.ac.cam.cl

LIBRARY REORGANIZATION: all_sets library
----------------------------------------

The all_sets library is currently being extensively revised and extended.
Additional theorems will be available, and we plan to add parser and
pretty-printer support for notation of the forms illustrated by:

   {x1,...,xn}    = a finite set
   {x | P x}      = the set of all x such that P
   {t[x] | P x}   = the set of all t[x] such that P x

Proof support for this notation will be provided by a derived inference rule
which does somthing like:

                  |- p[a1,...,an]
   ------------------------------------------------
   |- t[a1,...,an] IN {t[x1,...,xn] | p[x1,...,xn]}

A significant number of users have this library useful, and we hope this
revision will make it even more useful.

If you are a user of all_sets, and want to make a contribution to the revised
library, you could help by sending me (tfm) any theorems that you have had to
add to the basic stock provided by library to support your application.  I
will do my best to incorporate these theorems (please also send the proofs)
into the new library.

Tom

