have : Positive (n——m) := pos_diff_gt.mpr ‹n > m›
ℕ : Type
inst✝ : Natural ℕ
n m : ℕ
natOrderTri : AA.ExactlyOneOfThree (n < m) (n ≃ m) (n > m)
c✝ : n > m
⊢ AA.OneOfThree (n——m ≃ 0) (Positive (n——m)) (Negative (n——m))
ℕ : Type
inst✝ : Natural ℕ
n m : ℕ
natOrderTri : AA.ExactlyOneOfThree (n < m) (n ≃ m) (n > m)
c✝ : n > m
this : Positive (n——m)
⊢ AA.OneOfThree (n——m ≃ 0) (Positive (n——m)) (Negative (n——m))