Lean4
/-- TODO: `LocallyFiniteOrder.toLocallyFiniteOrderBot` is probably a bad instance, as it forms
a diamond with this instance, and constructs data from data. We should consider removing it. -/
example [Fintype α] [Preorder α] [Preorder β] [OrderBot α] [OrderBot β] [OrderTop α] [LocallyFiniteOrder α]
[LocallyFiniteOrder β] : LocallyFiniteOrder.toLocallyFiniteOrderBot = instLocallyFiniteOrderBot (α := α) (β := β) :=
by
try
with_reducible_and_instances
rfl -- fails
try
rfl -- fails
exact Subsingleton.elim _ _