(motive : Option Lean.Meta.Grind.NewFact → Sort u_1) →
  (__discr : Option Lean.Meta.Grind.NewFact) →
    ((next : Lean.Meta.Grind.NewFact) → motive (some next)) →
      ((x : Option Lean.Meta.Grind.NewFact) → motive x) → motive __discr