Section Restrict.
Variables (aT : finGroupType) (D : {set aT}) (rT : Type).
Variables (to : action D rT) (A : {set aT}).
Definition ract of A \subset D := act to.
Variable sAD : A \subset D.
Canonical raction := Action ract_is_action.

Lemma ractE : raction =1 to. Proof. by []. Qed.