On 28-07-2022 06:55, bokr@bokr.com wrote:
Lots of systems are dealing with this issue, it seems, judging from
[1] https://en.wikipedia.org/wiki/Bottom_type

I don't think it's a bottom type -- *unspecified* _is_ a value, so if we assign a type to it, it is inhabited, and hence not a bottom type. I

What about using characters from some private upper unicode section
to represent various kinds of unspecified things? E.g.,
as guile named chars,

 suppose you could subdivide the *unspecified* value, but why characters?

I think it would be better to:

though more something for guile-devel@ I suppose.