<source>:10:19: error: no match for 'operator<<' (operand types are 'std::ostream' {aka 'std::basic_ostream<char>'} and 'std::ranges::split_view<std::ranges::ref_view<std::__cxx11::basic_string<char> >, std::ranges::single_view<char> >::_OuterIter<true>::value_type')