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