>>>>> Roland Fu? via R-devel
>>>>> on Wed, 22 Oct 2025 10:24:07 +0200 writes:
> This doesn't seem intended.
You are right. The code change, reverting to previous behaviour
notably for "Date",
was prompted on this R-devel list,
https://stat.ethz.ch/pipermail/r-devel/2022-July/081850.html
But that the change allows poly(<factor>, .) to work was overlooked (by
me and anyone else ..) and is a bug we will change.
> See:
>
https://stackoverflow.com/questions/79795583/why-does-poly-work-for-unordered-factors-it-previously-did-not-work
As was already raised in the above SO thread,
what should happen for *ordered* factors is less obvious.
A warning was proposed, but I thought that this was too harsh;
hence, we could use message(), or just keep allowing it.
Opinions?
Martin
--
Martin Maechler
ETH Zurich and R Core team
> --
> Dr. Roland Fu?
> Th?nen-Institut f?r Agrarklimaschutz/
> Th?nen Institute of Climate-Smart Agriculture
> Bundesallee 65
> D-38116 Braunschweig, Germany