Definition CRmorph_compose {R1 R2 R3 : ConstructiveReals}
(f : @ConstructiveRealsMorphism R1 R2)
(g : @ConstructiveRealsMorphism R2 R3)
: @ConstructiveRealsMorphism R1 R3.

Lemma CRmorph_zero : forall {R1 R2 : ConstructiveReals}
(f : @ConstructiveRealsMorphism R1 R2),
CRmorph f 0 == 0.