15#ifndef dealii_cxx17_variant_h
16#define dealii_cxx17_variant_h
20#ifdef DEAL_II_HAVE_CXX17
24# include <boost/variant.hpp>
31#ifndef DEAL_II_HAVE_CXX17
35 template <
typename T,
typename... Ts>
37 holds_alternative(
const boost::variant<Ts...> &v)
noexcept
39 return boost::get<T>(&v) !=
nullptr;
43 using std::holds_alternative;
#define DEAL_II_NAMESPACE_OPEN
#define DEAL_II_DISABLE_EXTRA_DIAGNOSTICS
#define DEAL_II_NAMESPACE_CLOSE
#define DEAL_II_ENABLE_EXTRA_DIAGNOSTICS