have : n ≃ m := Natural.compare_eq.mp this
ℕ : Type
inst✝ : Natural ℕ
n m : ℕ
x✝ : (n——m).sgn ≃ 0
this✝¹ : ord_sgn (compare n m) ≃ 0
this✝ : ord_sgn (compare n m) ≃ ord_sgn Ordering.eq
this : compare n m = Ordering.eq
⊢ n——m ≃ 0
ℕ : Type
inst✝ : Natural ℕ
n m : ℕ
x✝ : (n——m).sgn ≃ 0
this✝² : ord_sgn (compare n m) ≃ 0
this✝¹ : ord_sgn (compare n m) ≃ ord_sgn Ordering.eq
this✝ : compare n m = Ordering.eq
this : n ≃ m
⊢ n——m ≃ 0