On Wed, Aug 28 2024, "Will Clinger" <xxxxxx@larcenists.org> wrote:

> You appear to be assuming there is some objective "actual meaning
> of x|p".  In my opinion, the purpose and specification of that notation
> has never been defined so well as to create an objectively actual
> meaning.

To provide some historical context, the notation's immediate ancestor is
this paper:

https://www.deinprogramm.de/sperber/papers/numerical-tower.pdf

See section 6.6 "External Representations".

The paper proposes a greater revision of the numerical tower in light of
its inconsistencies and practical problems.  In that context, 0.7|52
denotes an exact (and thus well-specified) number.  Within the greater
debate, some minor suggestions from that paper were adopted for R6RS -
such as the mantissa-width tagged format - but (sadly IMHO) the greater
proposal was not, leading to the imprecisions in the R6RS wording.

--
Regards,
Mike

Dr. Michael Sperber
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