On 26 Sep 2024, at 20:39, Marc Nieper-Wißkirchen <xxxxxx@gmail.com> wrote:

> Ah, now I understand the confusion.  I am using a "weak pair" in the sense of Chez, where the value is retained even if the key is broken.  In any case, this is an example of a mutable data structure where it would be inefficient to wrap each weak box.

Ah!

I would suggest that since this is an efficiency matter only, weak pairs of this kind would belong in the Batteries. We can think about them later.

Daphne