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Re: [Scheme-reports] "unspecified values"
On Fri 20 May 2011 17:46, John Cowan <cowan@x> writes:
> Andy Wingo scripsit:
>> I think that Per is saying that if `set!' returns no values, then
>> there is nothing for P to ignore.
> Sure. But "making the REPL nicer" is not an argument in favor of set!
> returning no values, as the REPL can be just as nice when set! returns a
> (distinguished) value.
I don't know why you insist on this being a *good* strategy, besides
being an allowable one.
For example with this repl:
(define (repl read eval print)
(let loop ()
(call-with-values (lambda () (eval (read)))
(for-each print vals)
What does it mean to return three distinguished unspecified values?
Surely it's different than returning one. Yet the user won't know in
such a system. (Incidentally Guile is such a system.)
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