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Re: Continuations

>>>>> "Steve" == Steve Dekorte <steve@dekorte.com> writes:

Steve> On Tuesday, August 12, 2003, at 11:30 PM, Michael Sperber wrote:
>> You can't start your VM, have it call C and C call
Steve> back and then safely create a real continuation.
Steve> >
>> You're just not reading what I'm writing:  You can.

Steve> Do we agree that the scheme page says you can't "continue" such a
Steve> continuation more than once:
Steve> http://www.s48.org/0.57/manual/s48manual_60.html

Steve> If so, we have a situation where continuations don't work properly
Steve> with C, which was my point. Does that make sense?

I'm beginning to get a glimpse of what you're trying to say, but you
sure are using the wrong terminology to say it.

You're saying things like "create a real continuation" which is just
nonsensical in this context: you probably mean "call CALL/CC" which
doesn't really "create a continuation"---it just gives you a packaged
version of the current one.  You're saying things like "don't work
properly" but you're using an idiosynchratic and only vaguely
specified notion of what "work properly" means in this context.

So: yes, there are restrictions on what you can do with the escape
procedures created by CALL/CC from a callback.  However, (speaking of
"safely") Scheme 48 detects and reports all violations of these
restrictions for you.  Moreover, there are still a lot of things left
you *can* do with those escape procedures.

Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla