Section Norm1vchar.
Variables (gT : finGroupType) (G : {group gT}).
Fact dirr_key : pred_key (dirr G). Proof. by []. Qed.
Canonical dirr_keyed := KeyedPred dirr_key.
Fact dirr_oppr_closed : oppr_closed (dirr G).

Lemma dirr_norm1 phi : phi \in 'Z[irr G] -> '[phi] = 1 -> phi \in dirr G.