Definition cfclass (A : {set gT}) (phi : 'CF(A)) (B : {set gT}) :=
[seq (phi ^ repr Tx)%CF | Tx in rcosets 'I_B[phi] B].
Local Notation "phi ^: G" := (cfclass phi G) : cfun_scope.

Lemma eq_cfclass_IirrE i j :
(cfclass_Iirr G j == cfclass_Iirr G i) = (j \in cfclass_Iirr G i).