English
A fold over a list with an accumulation of implications yields a universal implication form: the fold equals a function that if all items hold then the final term holds.
Русский
Свёртка по списку с накоплением импликаций даёт унифицированную форму импликаций: свёртка эквивалентна импликации от всех элементов.
LaTeX
$$$ (l.foldr BoundedFormula.imp f l).Realize v xs = ((\forall i \in l, i.Realize v xs) \rightarrow f.Realize v xs) $$$
Lean4
@[simp]
theorem realize_foldr_inf (l : List (L.BoundedFormula α n)) (v : α → M) (xs : Fin n → M) :
(l.foldr (· ⊓ ·) ⊤).Realize v xs ↔ ∀ φ ∈ l, BoundedFormula.Realize φ v xs := by
induction l with
| nil => simp
| cons φ l ih => simp [ih]