// sol2 // The MIT License (MIT) // Copyright (c) 2013-2021 Rapptz, ThePhD and contributors // Permission is hereby granted, free of charge, to any person obtaining a copy of // this software and associated documentation files (the "Software"), to deal in // the Software without restriction, including without limitation the rights to // use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of // the Software, and to permit persons to whom the Software is furnished to do so, // subject to the following conditions: // The above copyright notice and this permission notice shall be included in all // copies or substantial portions of the Software. // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS // FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR // COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN // CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. #ifndef SOL_OPTIONAL_HPP #define SOL_OPTIONAL_HPP #include <sol/forward.hpp> #include <sol/in_place.hpp> #include <sol/traits.hpp> #if SOL_IS_ON(SOL_USE_BOOST_I_) #include <boost/optional.hpp> #else #include <sol/optional_implementation.hpp> #endif // Boost vs. Better optional #include <optional> namespace sol { #if SOL_IS_ON(SOL_USE_BOOST_I_) template <typename T> using optional = boost::optional<T>; using nullopt_t = boost::none_t; SOL_BOOST_NONE_CONSTEXPR_I_ nullopt_t nullopt = boost::none; #endif // Boost vs. Better optional namespace meta { template <typename T> using is_optional = any<is_specialization_of<T, optional>, is_specialization_of<T, std::optional>>; template <typename T> constexpr inline bool is_optional_v = is_optional<T>::value; } // namespace meta namespace detail { template <typename T> struct associated_nullopt { inline static constexpr std::nullopt_t value = std::nullopt; }; #if SOL_IS_ON(SOL_USE_BOOST_I_) template <typename T> struct associated_nullopt<boost::optional<T>> { inline static SOL_BOOST_NONE_CONSTEXPR_I_ boost::none_t value = boost::none; }; #endif // Boost nullopt #if SOL_IS_ON(SOL_USE_BOOST_I_) template <typename T> inline SOL_BOOST_NONE_CONSTEXPR_I_ auto associated_nullopt_v = associated_nullopt<T>::value; #else template <typename T> inline constexpr auto associated_nullopt_v = associated_nullopt<T>::value; #endif // Boost continues to lag behind, to not many people's surprise... } // namespace detail } // namespace sol #if SOL_IS_ON(SOL_USE_BOOST_I_) #undef SOL_BOOST_NONE_CONSTEXPR_I_ #endif #endif // SOL_OPTIONAL_HPP