51 using string_view = std::string_view;  variable
159 class string_view {
177   constexpr string_view() noexcept : ptr_(nullptr), length_(0) {}  in string_view()  function
182   string_view(  // NOLINT(runtime/explicit)  in string_view()  function
187       : string_view(str.data(), str.size()) {}  in string_view()
192   constexpr string_view(const char* str)  // NOLINT(runtime/explicit)  in string_view()  function
197   constexpr string_view(const char* data, size_type len)  in string_view()  function
354   void swap(string_view& s) noexcept {  in swap()
391   constexpr string_view substr(size_type pos, size_type n = npos) const {
395                   string_view())
396                : string_view(ptr_ + pos, Min(n, length_ - pos));
407   constexpr int compare(string_view x) const noexcept {  in compare()
417   int compare(size_type pos1, size_type count1, string_view v) const {  in compare()
423   int compare(size_type pos1, size_type count1, string_view v, size_type pos2,  in compare()
430   int compare(const char* s) const { return compare(string_view(s)); }  in compare()
435     return substr(pos1, count1).compare(string_view(s));  in compare()
442     return substr(pos1, count1).compare(string_view(s, count2));  in compare()
452   size_type find(string_view s, size_type pos = 0) const noexcept;
463   size_type rfind(string_view s, size_type pos = npos) const
475   size_type find_first_of(string_view s, size_type pos = 0) const
490   size_type find_last_of(string_view s, size_type pos = npos) const
505   size_type find_first_not_of(string_view s, size_type pos = 0) const noexcept;
516   size_type find_last_not_of(string_view s,
568 constexpr bool operator==(string_view x, string_view y) noexcept {
574 constexpr bool operator!=(string_view x, string_view y) noexcept {
578 constexpr bool operator<(string_view x, string_view y) noexcept {
582 constexpr bool operator>(string_view x, string_view y) noexcept {
586 constexpr bool operator<=(string_view x, string_view y) noexcept {
590 constexpr bool operator>=(string_view x, string_view y) noexcept {
595 std::ostream& operator<<(std::ostream& o, string_view piece);
611 inline string_view ClippedSubstr(string_view s, size_t pos,
612                                  size_t n = string_view::npos) {
622 constexpr string_view NullSafeStringView(const char* p) {  in NullSafeStringView()
623   return p ? string_view(p) : string_view();  in NullSafeStringView()