Commit 2021-07-13 12:28 3e56439d
View on Github →chore(data/set/intervals): relax linear_order to preorder in the proofs of Ixx_eq_empty_iff (#8071)
The previous formulations of Ixx_eq_empty(_iff) are basically a chaining of this formulation plus not_lt or not_le. But not_lt and not_le require linear_order. Removing them allows relaxing the typeclasses assumptions on Ixx_eq_empty_iff and slightly generalising Ixx_eq_empty.