English
For φ: M →[L] N and a function symbol f of arity n, applying φ to the evaluation of f on x is the same as evaluating f on φ∘x.
Русский
Для φ: M →[L] N и символьной функции f арности n, применение φ к значению f над x равно значению f над φ∘x.
LaTeX
$$$\\phi\\,(\\mathrm{funMap}\\ f\\ x) = \\mathrm{funMap}\\ f\\ (\\phi\\circ x)$$$
Lean4
@[simp]
theorem map_fun (φ : M →[L] N) {n : ℕ} (f : L.Functions n) (x : Fin n → M) : φ (funMap f x) = funMap f (φ ∘ x) :=
HomClass.map_fun φ f x