Section InvLfun.
Variable (K : fieldType) (aT : FalgType K).
Implicit Types f g : 'End(aT).
Definition lfun_invr f := if lker f == 0%VS then f^-1%VF else f.
Canonical amull_additive := Eval hnf in Additive amull_is_linear.
Canonical amull_linear := Eval hnf in AddLinear amull_is_linear.

(* amull is a converse ring morphism *)
Lemma amull1 : amull 1 = \1%VF.