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Re: [Scheme-reports] Fwd: Comments on draft 6 about call/cc

Alaric Snell-Pym writes:

> Now, is my understanding that (> call/pc call/cc) true in all cases,
> or not? Does anybody know of any counter-examples?
> Clearly, it's far too late for call/cc to be replaced by delimited
> continuations for R7RS, but it would be nice to decide if it might
> be worth considering for R8RS (along with immutable-by-default
> pairs, perhaps? :-)

Such things should be considered for the large language now. If they
can be implemented in terms of the small language, great, let us have
them as a library, and implementations may be able to do them more
efficiently. If not, then there are weaknesses in the small language
that need to be understood and removed.

I wrote a generator library in terms of call/cc (and r6RS exceptions).
It was inspired by a broken attempt by someone else. It might have
been easier and more natural with delimited continuations, which I
have only read about, and I'm still worried about its correctness, in
the ways suggested in this thread, so I'm not entirely happy with
call/cc. Do not remove it, but maybe do look for a replacement.

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