tagged.h

 
//          Copyright John McFarlane 2019.
// Distributed under the Boost Software License, Version 1.0.
//    (See accompanying file ../LICENSE_1_0.txt or copy at
//          http://www.boost.org/LICENSE_1_0.txt)
 
#if !defined(CNL_IMPL_OPERATORS_TAGGED_H)
#define CNL_IMPL_OPERATORS_TAGGED_H
 
#include "../../constant.h"
#include "../config.h"
#include "../custom_operator/tag.h"
#include "definition.h"
#include "op.h"
 
#include <type_traits>
#include <utility>
 
namespace cnl {
    template<tag DestTag, typename Dest, tag SrcTag = _impl::native_tag>
    struct convert {
        template<typename Src>
        [[nodiscard]] constexpr auto operator()(Src const& src) const
        {
            return custom_operator<_impl::convert_op, op_value<Src, SrcTag>, op_value<Dest, DestTag>>{}(src);
        }
 
        template<CNL_IMPL_CONSTANT_VALUE_TYPE Value>
        [[nodiscard]] constexpr auto operator()(constant<Value> const& src) const
        {
            return custom_operator<_impl::convert_op, op_value<decltype(Value), SrcTag>, op_value<Dest, DestTag>>{}(src);
        }
    };
 
    namespace _impl {
        template<op Operator, tag Tag = native_tag>
        struct operate {
            template<typename... Operands>
            [[nodiscard]] constexpr auto operator()(Operands const&... operands) const
            {
                return custom_operator<Operator, op_value<Operands, Tag>...>{}(operands...);
            }
 
            template<typename... Operands>
            constexpr auto operator()(Operands&&... operands) const
            {
                return custom_operator<
                        Operator,
                        op_value<std::remove_cvref_t<Operands>, Tag>...>{}(std::forward<Operands>(operands)...);
            }
        };
    }
}
 
#endif  // CNL_IMPL_OPERATORS_TAGGED_H