How to use a non const erased type ? about te HOT 2 CLOSED

struct viewer_storage {
  template <class T, class T_ = std::decay_t<T> >
  constexpr explicit viewer_storage(T &&t, te::detail::void_ptr &ptr) noexcept {
    ptr.reset(&t, 
        []([[maybe_unused]] void *ptr) {},
        [](void *ptr) -> void * { return static_cast<T_ *>(ptr); });
  }
};