Am So., 30. Aug. 2020 um 16:34 Uhr schrieb John Cowan <xxxxxx@ccil.org>:
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> On Sun, Aug 30, 2020 at 4:41 AM Marc Nieper-Wißkirchen <xxxxxx@nieper-wisskirchen.de> wrote:
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>> All that's fine if the following implementation is also possible:
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> No such fallback is necessary, because the procedures of this SRFI are only applicable to objects that satisfy `nan?` and, as you point out, `real?`.  I have added a paragraph in the Specification section emphasizing that these procedures are only to be called on objects satisfying those predicates.  (I have also added calls to `assume` to catch complex numbers.)
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> If the implementation treats only some of the objects whose representation uses the bit-patterns of IEEE NaNs as satisfying `nan?`, so be it: they will satisfy `character?` or `fixnum?` or `eof-object?` or `pair?' or whatever, but not `nan?`.  If the implementation is running on a Vax or an IBM mainframe (as is possible for Schemes that compile to C), then nothing will satisfy `nan?`, in which case the procedures should never be called at all.
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> Does that satisfy your concerns?

Yes, thanks. What you write makes perfect sense!

Marc