std::ranges::viewable_range - A range which can be safely converted to a view.

       Generated automatically by Doxygen for libstdc++ from the source code.

                                                    libstdc++                  std::ranges::viewable_range(3cxx)

       template<typename _Tp>
       concept std::ranges::viewable_range =  range<_Tp>
             && ((view<remove_cvref_t<_Tp>> && constructible_from<remove_cvref_t<_Tp>, _Tp>)
                 || (!view<remove_cvref_t<_Tp>>
                     && (is_lvalue_reference_v<_Tp>
                         || (movable<remove_reference_t<_Tp>>
                             && !__detail::__is_initializer_list<remove_cvref_t<_Tp>>))))

       A range which can be safely converted to a view.

       std::ranges::viewable_range - A range which can be safely converted to a view.

       #include <ranges>