sigma_closed_issmall@{i j | } {A : Type@{j}} (B : A -> Type@{j}) (sA : IsSmall@{i j} A) (sB : forall a, IsSmall@{i j} (B a)) : IsSmall@{i j} { a : A & B a }. Proof. exists { a : (smalltype A) & (smalltype (B (equiv_smalltype A a))) }. snrapply equiv_functor_sigma'; intros; apply equiv_smalltype. Defined.
Require Import Basics.Overture Basics.Equivalences Basics.Trunc Basics.Tactics