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Re: [Scheme-reports] Some comments after reading the r7rs public draft

On Mon, Jun 11, 2012 at 2:27 PM, John Cowan <cowan@x> wrote:
> Alex Shinn scripsit:
>> The other cases I think should always be auto-forced -
>> they would simply be errors anyway.
> In what sense would it be an error to ask if (delay 3) is eqv? to 3?

Sorry, this would not be an error, but is consistent with
the rule of auto-forcing and with the optional extension
for (delay 3) => 3.

> I note that although deliberate uses of `write` and `display` force
> promises in Chibi, the default REPL does not, printing #<"Promise">.

I think that's reasonable.  In the REPL you can always see the
promise and manually force.  In a program writing to a data file,
writing a non-readable #<Promise> is broken.


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