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From: gjr@hplgr2.hpl.hp.com (Guillermo (Bill) J. Rozas)
Subject: Re: expressiveness and strong type system?
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In-Reply-To: blume@zayin.cs.princeton.edu's message of 28 Mar 1996 19:48:35 GMT
Date: Sun, 31 Mar 1996 14:24:14 GMT
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In article <BLUME.96Mar28144835@zayin.cs.princeton.edu> blume@zayin.cs.princeton.edu (Matthias Blume) writes:

|      Interesting.  However, if this is done, aren't you violating the
|      opacity of your types?  The "violator" can merely dump the object,
|      muck around with the external representation, and reload it.
|
|   Yes, that would be possible, although a checksumming/encryption
|   mechanism might be able to make it sufficiently hard.

Yes, but that is also possible for non-opaque Scheme types, so we are
talking now of convenience and effort on the part of the implementor
and user, not capability.
