simp_rw [hI.inter_basis_cl_iff_subset_cl_inter] at hXs
ι : Type u_1
α : Type u_2
M : Matroid α
B I J X X' Y Y' F : Set α
Xs Ys Js Is : ι → Set α
i j : ι
e f : α
hI : M.Indep I
hXs : ∀ (i : ι), M.Basis (Xs i ∩ I) (Xs i)
⊢ M.ModularFamily Xs
ι : Type u_1
α : Type u_2
M : Matroid α
B I J X X' Y Y' F : Set α
Xs Ys Js Is : ι → Set α
i j : ι
e f : α
hI : M.Indep I
hXs : ∀ (i : ι), Xs i ⊆ M.cl (Xs i ∩ I)
⊢ M.ModularFamily Xs