Am So., 16. Aug. 2020 um 16:06 Uhr schrieb Lassi Kortela <xxxxxx@lassi.io>:

> I believe the question "did this error come from POSIX?" is nonsensical.
> POSIX is not a definite piece of software on a computer. It makes more

+1. I think this remark makes a lot of sense. (I think it is
analogously nonsensically to ask for full implementation of POSIX in
Scheme.)

> The question "did this error come from the C errno variable, and if so,
> which value?" may make sense to ask, but is less useful than the above
> questions and orthogonal to them.

Given that the C code runs parallel with a VM, even this may not be
sensible to ask (see the discussion of SRFI 199).

> I also believe it's wise for 170 to mandate (or at least strongly
> recommend) its errors to have properties that are not wise to require in
> all 198 objects. 170 errors are much easier to understand than the
> universe of all potential 198 objects.

> > I don't see the linkage here.  What would be exotic enough that it
> > can't be represented by all three of the above options? They're all
> > lists of one sort or another.

> By exotic properties I meant ones related SQL, HTTP, IRC and various
> others that are not urgent for SRFI 170.

The closer the error reporting of SRFI 170 is tied to the underlying
system calls (which are actually calls into the C library I think),
the simpler SRFI 170 is to understand.

> > an alist and a plist take the same number of cons cells to collect
> > their key/value pairs (and I note alists are messier for list values).

In what sense are they messier?

PS: Lassi, at some point we should continue with our work on alists.