#[global]
Instance CR_cv_morph
: forall {R : ConstructiveReals} (un : nat -> CRcarrier R), CMorphisms.Proper
(CMorphisms.respectful (CReq R) CRelationClasses.iffT) (CR_cv R un).

Lemma CR_cv_dist_cont : forall {R : ConstructiveReals}
(u : nat -> CRcarrier R) (a s : CRcarrier R),
CR_cv R u s
-> CR_cv R (fun n => CRabs R (a - u n)) (CRabs R (a - s)).