English
A simp-lemma for evalFrom under comap: the same as above, expressed for a simp attribute.
Русский
Упрощённая лемма для evalFrom под comap: то же самое выражено через simp-атрибут.
LaTeX
$$$ @[simp] \; \text{theorem} \; M.{\mathrm{evalFrom}}(s, x) = M.{\mathrm{evalFrom}}(s, x.map f) $$$
Lean4
@[simp]
theorem eval_comap (f : α' → α) (x : List α') : (M.comap f).eval x = M.eval (x.map f) := by simp [eval]