Commit 2023-02-13 19:19 48085f14
View on Github →chore(algebra/quaternion): generalize the algebra instance (#18382)
To prevent this generalization forming diamonds, we have to now populate the nsmul, zsmul, and qsmul fields.
I use this in another PR to talk about the R algebra structure of quaternion (dual_number R).
Even without that motivation, this change means that the existing smul lemmas now apply to nsmul, zsmul, and rat_smul where previously they did not.