fact: Definition hfiber_functor_hfiber {A B C D} {f : A -> B} {g : C -> D} {h : A -> C} {k : B -> D} (p : k o f == g o h) (b : B) (c : C) (q : g c = k b) : hfiber (functor_hfiber p b) (c;q) <~> hfiber (functor_hfiber (fun x => (p x)^) c) (b;q^).
imports: Basics Types Diagrams.CommutativeSquares HSet