fact: Definition i2cons2 {a : A} {n} {l : Vector.t A n} (b1 : B a) (il1 : ilist (B := B) l) (b2 : B' a) (il2 : ilist (B := B') l) (c : C b1 b2) (i2l' : i2list2 l il1 il2) : i2list2 (a :: l) (icons b1 il1) (icons b2 il2) := {| prim_fst := c; prim_snd := i2l' |}.
imports: Coq.Lists.List Coq.Strings.String Coq.Arith.Arith Fiat.Common.ilist Fiat.Common.ilist2