(motive : Lean.Meta.DiscrTree.Key → Sort u_1) →
  (x : Lean.Meta.DiscrTree.Key) →
    ((n : Lean.Name) → (a : ℕ) → motive (Lean.Meta.DiscrTree.Key.const n a)) →
      ((n : Lean.FVarId) → (a : ℕ) → motive (Lean.Meta.DiscrTree.Key.fvar n a)) →
        ((v : Lean.Literal) → motive (Lean.Meta.DiscrTree.Key.lit v)) →
          (Unit → motive Lean.Meta.DiscrTree.Key.star) →
            (Unit → motive Lean.Meta.DiscrTree.Key.other) →
              (Unit → motive Lean.Meta.DiscrTree.Key.arrow) →
                ((s : Lean.Name) → (i a : ℕ) → motive (Lean.Meta.DiscrTree.Key.proj s i a)) → motive x