English
A variant of restrictFreeVar with a subset specified by a decision procedure; realization is preserved.
Русский
Вариант restrictFreeVar с подмножеством, заданным decidable, сохраняет реализацию.
LaTeX
$$$ [\DecidableEq α] \; (\phi.restrictFreeVar (Set.inclusion h)).Realize (v \circ (\uparrow)) xs \iff \phi.Realize v xs $$$
Lean4
/-- A special case of `realize_restrictFreeVar`, included because we can add the `simp` attribute
to it -/
@[simp]
theorem realize_restrictFreeVar' [DecidableEq α] {n : ℕ} {φ : L.BoundedFormula α n} {s : Set α}
(h : ↑φ.freeVarFinset ⊆ s) {v : α → M} {xs : Fin n → M} :
(φ.restrictFreeVar (Set.inclusion h)).Realize (v ∘ (↑)) xs ↔ φ.Realize v xs :=
realize_restrictFreeVar _ (by simp)