Theorem: Matroid.skew_iff_of_loopEquiv (Matroid/Modular.lean)

State before:
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
hX : M.LoopEquiv X X'
hY : M.LoopEquiv Y Y'
⊢ M.Skew X Y ↔ M.Skew X' Y'
Tactic:
refine ⟨fun h ↦ ?_, fun h ↦ ?_⟩
State after:
case refine_1
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
hX : M.LoopEquiv X X'
hY : M.LoopEquiv Y Y'
h : M.Skew X Y
⊢ M.Skew X' Y'

case refine_2
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
hX : M.LoopEquiv X X'
hY : M.LoopEquiv Y Y'
h : M.Skew X' Y'
⊢ M.Skew X Y

State before:
case refine_2
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
hX : M.LoopEquiv X X'
hY : M.LoopEquiv Y Y'
h : M.Skew X' Y'
⊢ M.Skew X Y
Tactic:
rwa [skew_iff_cl_skew hX.symm.subset_ground hY.symm.subset_ground, hX.cl_eq_cl, hY.cl_eq_cl,
    ← skew_iff_cl_skew]
State after:
no goals

State before:
case refine_1
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
hX : M.LoopEquiv X X'
hY : M.LoopEquiv Y Y'
h : M.Skew X Y
⊢ M.Skew X' Y'
Tactic:
rwa [skew_iff_cl_skew hX.subset_ground hY.subset_ground, ← hX.cl_eq_cl, ← hY.cl_eq_cl,
  ← skew_iff_cl_skew]
State after:
no goals