English
The recursive reverse on an empty list yields the base motive value.
Русский
Рекурсивное обращение списка по пустому списку даёт базовое значение мотива.
LaTeX
$$$$ \operatorname{reverseRecOn} (\text{motive}) ([]) = nil. $$$$
Lean4
@[simp]
theorem reverseRecOn_nil {motive : List α → Sort*} (nil : motive [])
(append_singleton : ∀ (l : List α) (a : α), motive l → motive (l ++ [a])) :
reverseRecOn [] nil append_singleton = nil :=
reverseRecOn.eq_1 ..
-- `unusedHavesSuffices` is getting confused by the unfolding of `reverseRecOn`