77   class _LIBCPP_TEMPLATE_VIS subrange
78     : public view_interface<subrange<_Iter, _Sent, _Kind>>
94     subrange() requires default_initializable<_Iter> = default;
97     constexpr subrange(__convertible_to_non_slicing<_Iter> auto __iter, _Sent __sent)  in subrange()  function
103     constexpr subrange(__convertible_to_non_slicing<_Iter> auto __iter, _Sent __sent,  in subrange()  function
113     template<__different_from<subrange> _Range>
118     constexpr subrange(_Range&& __range)  in subrange()  function
120       : subrange(ranges::begin(__range), ranges::end(__range))  in subrange()
123     template<__different_from<subrange> _Range>
128     constexpr subrange(_Range&& __range)  in subrange()  function
130       : subrange(__range, ranges::size(__range))  in subrange()
137     constexpr subrange(_Range&& __range, make_unsigned_t<iter_difference_t<_Iter>> __n)  in subrange()  function
139       : subrange(ranges::begin(__range), ranges::end(__range), __n)  in subrange()
142     template<__different_from<subrange> _Pair>
177 …[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange next(iter_difference_t<_Iter> __n = 1) cons…
185 … [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange next(iter_difference_t<_Iter> __n = 1) && {
190 …[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr subrange prev(iter_difference_t<_Iter> __n = 1) const
199     constexpr subrange& advance(iter_difference_t<_Iter> __n) {  in advance()
217   subrange(_Iter, _Sent) -> subrange<_Iter, _Sent>;
220   subrange(_Iter, _Sent, make_unsigned_t<iter_difference_t<_Iter>>)
221     -> subrange<_Iter, _Sent, subrange_kind::sized>;
224   subrange(_Range&&) -> subrange<iterator_t<_Range>, sentinel_t<_Range>,
229   subrange(_Range&&, make_unsigned_t<range_difference_t<_Range>>)
230     -> subrange<iterator_t<_Range>, sentinel_t<_Range>, subrange_kind::sized>;
235   constexpr auto get(const subrange<_Iter, _Sent, _Kind>& __subrange) {  in get()
245   constexpr auto get(subrange<_Iter, _Sent, _Kind>&& __subrange) {  in get()
253   inline constexpr bool enable_borrowed_range<subrange<_Ip, _Sp, _Kp>> = true;
256   using borrowed_subrange_t = _If<borrowed_range<_Rp>, subrange<iterator_t<_Rp>>, dangling>;
266 struct tuple_size<ranges::subrange<_Ip, _Sp, _Kp>> : integral_constant<size_t, 2> {};
269 struct tuple_element<0, ranges::subrange<_Ip, _Sp, _Kp>> {
274 struct tuple_element<1, ranges::subrange<_Ip, _Sp, _Kp>> {
279 struct tuple_element<0, const ranges::subrange<_Ip, _Sp, _Kp>> {
284 struct tuple_element<1, const ranges::subrange<_Ip, _Sp, _Kp>> {