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Re: [Scheme-reports] "the result is unspecified" vs "unspecified values"

First, thank you very much for all your feedback, in this
current burst and throughout the process.

On Sun, Jan 6, 2013 at 4:10 AM, Andy Wingo <wingo@x> wrote:
I think the R6RS did the right thing in allowing e.g. `(set! foo 10)' to
result in 0 values, and that R7RS did the wrong thing in reverting to
the R5RS "the result is unspecified".  Some expressions just don't have
useful values, and forcing implementations to produce a value in that
case hides bugs, producing programs with less meaning.

You've raised this issue before.  Also, from your mail on I/O:
Call-with-port not closing the port in exceptional situations is a
shame.  As it is, the only thing you can do to close ports in
exceptional situations is to use dynamic-wind.  Nasty.

You've raised this issue before.  We've discussed both to
death.  People feel very strongly on both sides, and I don't
see any progress being made, so I'm not clear on your
motivation for bringing it up again.

If you want to provide a list of everything you don't like about
R7RS (which I think is an excellent idea, and something I'm
planning myself), it's probably better to write up a single

Thanks again,


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