(motive : List (Lean.Language.SnapshotTask Lean.Language.SnapshotTree) → Sort u_1) →
  (x : List (Lean.Language.SnapshotTask Lean.Language.SnapshotTree)) →
    (Unit → motive []) →
      ((child : Lean.Language.SnapshotTask Lean.Language.SnapshotTree) →
          (otherChildren : List (Lean.Language.SnapshotTask Lean.Language.SnapshotTree)) →
            motive (child :: otherChildren)) →
        motive x