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Issue: FORMAT-PRETTY-PRINT (version 2)

I support the idea of this proposal and more or less support its stance
on the issue, but I have a few suggestions on presentation...

I think this proposal should have the same character as the one about
FORMAT-NEGATIVE-PARAMETERS -- it should define the default situation
(ie, the expository text which precedes the detail section of the FORMAT
chapter) and allow the description of any given parameter to override
what it says. That would address Walter's concern about ~D. We should not
make the wording fuzzy enough for any dialect to get something in that
people don't expect. Instead, we should consider Walter's suggestion
that ~D should bind *PRINT-ESCAPE* (btw, Symbolics Genera does this, too).
If we think it's a good suggestion, we should just override the default
rule which Dan's proposing with an explicit rule for how ~D behaves. But
in the absence of such a rule, I think that ~D should either not bind
*PRINT-ESCAPE* or be an error for anything for which the value of 
*PRINT-ESCAPE* could make a difference. (And since we'll presumably be
able to customize the printing of integers once CLOS goes in, I think
we'd be best of just defining the value of *PRINT-ESCAPE* in this situation
just in case...)

I think the rationale should mention that the key advantage would be
that people can treat (FORMAT stream "~S" object) and (PRIN1 object)
as purely a stylistic difference and interchangeable at any time. If they
have to worry that one treats the control variables differently than the
other, then the language is complicated in a way that is not generally
useful to the garden-variety programmer...