{motive : Lean.Expr → Sort u} →
  (t : Lean.Expr) →
    ((declName : Lean.Name) →
        (type value body : Lean.Expr) → (nondep : Bool) → motive (Lean.Expr.letE declName type value body nondep)) →
      (Nat.hasNotBit 256 t.ctorIdx → motive t) → motive t