English
There is a canonical FunLike structure on NonarchAddGroupNorm E turning each element into a real-valued function on E, with coe f := f.toFun and an injective coercion.
Русский
Существует каноническая структура FunLike на NonarchAddGroupNorm E, превращающая элемент в функцию E → ℝ, с определением отображения и инъекцией коэрции.
LaTeX
$$There is a FunLike structure: $\text{coe}(f) = f.toFun$ with $\text{coe}$ injective$$
Lean4
instance funLike : FunLike (NonarchAddGroupNorm E) E ℝ
where
coe f := f.toFun
coe_injective' f g h := by obtain ⟨⟨⟨_, _⟩, _, _⟩, _⟩ := f; cases g; congr