Re: issue QUOTE-MAY-COPY, version 2

[sandra%defun@cs.utah.edu (Sandra J Loosemore)]

> Date: Wed, 14 Dec 88 00:34:11 PST
> From: Jon L White <jonl@lucid.com>
> 
> re: QUOTE-MAY-COPY:ALWAYS
> 
> To me, the choice of names for this alternative is somewhat loaded; it
> seems to imply "excesssive, copying work must ALWAYS take place".  How
> about a name like EXPLICITLY-VAGUE?

Fine with me.

> re:   If an implementation chooses to copy constants, the copying may only
>       happen once each time the form containing the constant is processed
>       with COMPILE or EVAL (see examples below).
> 
> This seems a bit fuzzy to me.  Why not simply say that successive
> evaluations of a form (QUOTE <foo>) must all be EQL?  then you could
> point out in an implementational note that this means you are restricted
> to copying a given instance of a constant at most once.

Frankly, your wording seems too vague to me.  I think it's important
to address the issues of what happens when the QUOTE form appears
inside of something passed to EVAL.  If EVAL is doing the copying in
some kind of preprocessor, then it is reasonable for each call to EVAL
to make its own copy.  Likewise, I think we must allow for the
possibility that COMPILE might make a fresh copy of all constants
inside the function whenever it is recompiled.  Perhaps I can think of
some better wording to express this, though.

-Sandra
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