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Diffstat (limited to 'boost/contract/detail/type_traits/optional.hpp')
| -rw-r--r-- | boost/contract/detail/type_traits/optional.hpp | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/boost/contract/detail/type_traits/optional.hpp b/boost/contract/detail/type_traits/optional.hpp new file mode 100644 index 0000000000..453df2f778 --- /dev/null +++ b/boost/contract/detail/type_traits/optional.hpp @@ -0,0 +1,42 @@ + +#ifndef BOOST_CONTRACT_DETAIL_OPTIONAL_HPP_ +#define BOOST_CONTRACT_DETAIL_OPTIONAL_HPP_ + +// Copyright (C) 2008-2018 Lorenzo Caminiti +// Distributed under the Boost Software License, Version 1.0 (see accompanying +// file LICENSE_1_0.txt or a copy at http://www.boost.org/LICENSE_1_0.txt). +// See: http://www.boost.org/doc/libs/release/libs/contract/doc/html/index.html + +#include <boost/optional.hpp> +#include <boost/type_traits/remove_reference.hpp> +#include <boost/type_traits/integral_constant.hpp> + +namespace boost { namespace contract { namespace detail { + +template<typename T> +struct is_optional : boost::false_type {}; +template<typename T> +struct is_optional<boost::optional<T> > : boost::true_type {}; + +template<typename T> +struct optional_value_type { typedef T type; }; +template<typename T> +struct optional_value_type<boost::optional<T> > { typedef T type; }; + +template<typename T> +struct remove_value_reference_if_optional { typedef T type; }; +template<typename T> +struct remove_value_reference_if_optional<boost::optional<T> > + { typedef typename boost::remove_reference<T>::type type; }; + +template<typename T> +T& optional_get(T& x) { return x; } +template<typename T> +T& optional_get(boost::optional<T>& x) { return x.get(); } +template<typename T> +T& optional_get(boost::optional<T&>& x) { return x.get(); } + +} } } // namespace + +#endif // #include guard + |