intuition.
apply evalDet_steps_done_inv in H.
destruct H.
destruct H.
intuition.
eapply evalDet_steps_trans.
eapply evalDet_steps_bind_more.
eauto.
econstructor.
simpl.
rewrite H1.
eauto.
econstructor.
Qed.

Theorem evalDet_bind_eof : forall(A B : Set)(c1 : Comp B)(c2 : B -> Comp A) s,
evalDet_steps (cs_more c1 s) (@cs_eof B) ->
evalDet_steps (cs_more (Bind c1 c2) s) (@cs_eof A).