{motive : Lean.Elab.Term.Do.JPDecl → Sort u} →
  ((name : Lean.Name) →
      (params : Array (Lean.Elab.Term.Do.Var × Bool)) →
        (body : Lean.Elab.Term.Do.Code) → motive { name := name, params := params, body := body }) →
    (t : Lean.Elab.Term.Do.JPDecl) → motive t