refine ⟨h.modularFamily.cls_modularFamily, fun i j hij ↦ ?_⟩
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
h : M.SkewFamily Xs
⊢ M.SkewFamily fun i => M.cl (Xs i)
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
h : M.SkewFamily Xs
i j : ι
hij : i ≠ j
⊢ (fun i => M.cl (Xs i)) i ∩ (fun i => M.cl (Xs i)) j ⊆ M.cl ∅