[R6RS] "read/write equivalence"

[Michael Sperber]

"R. Kent Dybvig" <dyb at cs.indiana.edu> writes:

>> Alan Watson correctly pointed out that it's impossible to require this
>> in a sensible way, essentially because of
>>
>> (eqv? +nan.0 nan+0) => unspecified
>>
>> I've weakened to spec of `put-datum' accordingly, essentially by
>> changing the "must" to a "should".
>
> Why not say "must" and list +nan.0 as an exception?  "should" is too
> strong because it slaps the hands of an implementation that has two
> representations for NaN, and "should" is too weak because it opens the
> door for all kinds of other exceptions.

Can you suggest a wording?

-- 
Cheers =8-} Mike
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