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Re: issue QUOTE-MAY-COPY, version 3
- To: Jon L White <@sail.stanford.edu:email@example.com>, firstname.lastname@example.org
- Subject: Re: issue QUOTE-MAY-COPY, version 3
- From: Jeff Dalton <jeff%aiai.edinburgh.ac.uk@NSS.Cs.Ucl.AC.UK>
- Date: Thu, 5 Jan 89 23:22:06 GMT
- Cc: email@example.com
- In-reply-to: Jon L White's message of Tue, 3 Jan 89 15:04:29 PST
> re: To say that QUOTE copies in existing implementations is to
> imply that a lot of copying might happen that never actually
> happens. COMPILE-FILE followed by LOAD effectively copies,
> and in KCL, COMPILE effectively makes a copy, but not QUOTE.
> This may be repeating previous points, but we've been maintaing that
> the phrase "QUOTE copies" does *not* mean that the function QUOTE
> does any work -- merely that the semantics of "quoted objects" is such
> that you cannot tell whether you got the "original" or some copy
[Or, rather, that any code that relies on the difference is in error.
You can, of course, tell, if you constructed the QUOTE form.]
I think I tried to make a point similar to Chris's. I asked whether
any inplementation copied in interpreted code. My recollection is
that the proposal claimed that disallowing copying in interpreted
code was inconsistent with current practice.
But anyway, if this issue is causing so much confusion, the proposal
should be reworded in a "semantics of quoted objects" way and not
left in "QUOTE may copy" style.