Re: [Scheme-reports] Multiple values in BEGIN
Jussi Piitulainen 06 May 2011 14:35 UTC
Andre van Tonder writes:
> On Fri, 6 May 2011, John Cowan wrote:
> > Ian Price scripsit:
> >
> >> "The continuations of all non-final expressions within a sequence of
> >> expressions, such as in lambda, begin, let, let*, letrec, letrec*,
> >> let-values, let*-values, case, and cond forms, usually take an
> >> arbitrary number of values."
> >
> > Ticket filed.
>
> Only non-final expressions, though?
>
> I don't like that restriction, because equivalence of the following two
> expressions should be to me a fundamental property of BEGIN:
>
> (begin
> (begin
> exp1)
> exp2))
>
> and
>
> (begin
> exp1
> exp2)
>
> But with ths stated restriction, they are not equivalent.
What difference do you see? These seem equivalent to me whether or not
the non-final expressions in a sequence are required to return exactly
one value.
I would like any number of values allowed, as in R6RS. (I don't know
why it says "usually".)
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