14#ifndef dealii_cxx17_optional_h
15#define dealii_cxx17_optional_h
19#ifdef DEAL_II_EARLY_DEPRECATIONS
21 "This file is deprecated. Simply use the corresponding C++17 header <optional>.")
#define DEAL_II_NAMESPACE_OPEN
#define DEAL_II_WARNING(desc)
#define DEAL_II_NAMESPACE_CLOSE