boost::text::v1::at_allowed_line_break
// In header: <boost/text/line_break.hpp> template<code_point_range R> bool at_allowed_line_break(R && r, std::ranges::iterator_t< R > it);
Returns true iff it is at the beginning of a line, or it == detail::end(range).
it
it == detail::end(range)
