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Re: issue QUOTE-MAY-COPY, version 1
- To: firstname.lastname@example.org
- Subject: Re: issue QUOTE-MAY-COPY, version 1
- From: cperdue@Sun.COM (Cris Perdue)
- Date: Wed, 14 Dec 88 12:59:57 PST
- Cc: email@example.com, jeff%aiai.edinburgh.ac.uk@NSS.Cs.Ucl.AC.UK
Taking this opportunity to also respond to a related earlier note
> . . .
> However, I don't think it is right to say that READ constructs up
> "constants". Note that READ absolutely cannot know whether some structure
> it cons'd up is a constant or not. A piece of data only becomes a program
> "constant" when it is EVAL'd in the proper context (or "compiled");
> otherwise, it is just as random as any other cons cell or string lying
> around in memory. . . .
My personal intuition is that (potentially) readonly constants are
created sometime during loading of a compiled file, and that as far
as a user of the language is concerned, the constants are *created*
in their coalesced, copied, readonly, or whatever state.
There may be other self-consistent and reasonable points of view. This
point of view makes sense to me, fits CLtL's existing specification of
QUOTE, and I think satisfies Pitman's concerns.