no goals
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a : α
x✝ : ¬a ∈ []
⊢ remove a [] = []
simp [remove]
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
h1 : a ≠ a'
⊢ remove a (a' :: as) = a' :: as
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
⊢ remove a (a' :: as) = a' :: as
have h1 : a ≠ a' := fun h' ↦ h (by rw [h']; apply mem_cons_self)
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
h1 : a ≠ a'
h2 : ¬a ∈ as
⊢ remove a (a' :: as) = a' :: as
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
h1 : a ≠ a'
⊢ remove a (a' :: as) = a' :: as
have h2 : a ∉ as := fun h' ↦ h (mem_cons_of_mem _ h')
no goals
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
h1 : a ≠ a'
h2 : ¬a ∈ as
⊢ remove a (a' :: as) = a' :: as
simp [remove, h1, remove_eq_of_not_mem h2]
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
h' : a = a'
⊢ a' ∈ a' :: as
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
h' : a = a'
⊢ a ∈ a' :: as
rw [h']
no goals
α : Type u_1
β : Sort ?u.19160
inst✝¹ : DecidableEq α
inst✝ : DecidableEq β
a a' : α
as : List α
h : ¬a ∈ a' :: as
h' : a = a'
⊢ a' ∈ a' :: as
apply mem_cons_self