[libc++] "Implements" new SI prefixis.

[Mordante]

Summary

Like yocto, zepto, zetta, and yotta. The new prefixes quecto, ronto,
ronna, and quetta can't be implemented in a intmax_t. So their
implementation does nothing.

Implements

• P2734R0 Adding the new SI prefixes

Depends on D153192

[Mordante]

Adds updated generated files.

[philnik]

libcxx/include/ratio

43

Otherwise this is really confusing.

[h-vetinari]

libcxx/include/ratio

65

libcxx/docs/FeatureTestMacroTable.rst

.. table:: Current Status
     ``__cpp_lib_copyable_function``                     *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_fstream_native_handle``                 *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_function_ref``                          *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_hazard_pointer``                        *unimplemented*
     --------------------------------------------------- -----------------
-    ``__cpp_lib_ratio``                                 *unimplemented*
+    ``__cpp_lib_ratio``                                 ``202306L``
     --------------------------------------------------- -----------------
     ``__cpp_lib_rcu``                                   *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_smart_ptr_owner_equality``              *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_sstream_from_string_view``              *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_submdspan``                             *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_text_encoding``                         *unimplemented*
     --------------------------------------------------- -----------------
     ``__cpp_lib_within_lifetime``                       *unimplemented*
     =================================================== =================
 

libcxx/docs/Status/Cxx2cPapers.csv

 "`P0792R14 <https://wg21.link/P0792R14>`__","LWG","``function_ref``: a type-erased callable reference","Varna June 2023","","",""
 "`P2874R2 <https://wg21.link/P2874R2>`__","LWG","Mandating Annex D Require No More","Varna June 2023","","",""
 "`P2757R3 <https://wg21.link/P2757R3>`__","LWG","Type-checking format args","Varna June 2023","","","|format|"
 "`P2637R3 <https://wg21.link/P2637R3>`__","LWG","Member ``visit``","Varna June 2023","","","|format|"
 "`P2641R4 <https://wg21.link/P2641R4>`__","CWG, LWG","Checking if a ``union`` alternative is active","Varna June 2023","","",""
 "`P1759R6 <https://wg21.link/P1759R6>`__","LWG","Native handles and file streams","Varna June 2023","","",""
 "`P2697R1 <https://wg21.link/P2697R1>`__","LWG","Interfacing ``bitset`` with ``string_view``","Varna June 2023","","",""
 "`P1383R2 <https://wg21.link/P1383R2>`__","LWG","More ``constexpr`` for ``<cmath>`` and ``<complex>``","Varna June 2023","","",""
-"`P2734R0 <https://wg21.link/P2734R0>`__","LWG","Adding the new SI prefixes","Varna June 2023","","",""
+"`P2734R0 <https://wg21.link/P2734R0>`__","LWG","Adding the new SI prefixes","Varna June 2023","|Complete|","Clang 17",""
 "`P2548R6 <https://wg21.link/P2548R6>`__","LWG","``copyable_function``","Varna June 2023","","",""
 "`P2714R1 <https://wg21.link/P2714R1>`__","LWG","Bind front and back to NTTP callables","Varna June 2023","","",""
 "`P2630R4 <https://wg21.link/P2630R4>`__","LWG","``submdspan``","Varna June 2023","","",""
 "","","","","","",""

libcxx/include/ratio

 template <class R1, class R2> struct ratio_equal;
 template <class R1, class R2> struct ratio_not_equal;
 template <class R1, class R2> struct ratio_less;
 template <class R1, class R2> struct ratio_less_equal;
 template <class R1, class R2> struct ratio_greater;
 template <class R1, class R2> struct ratio_greater_equal;
 
 // convenience SI typedefs
+using quecto = ratio <1 , 1'000'000'000'000'000'000'000'000'000'000>; // Since C++26 not supported
+using ronto = ratio <1 , 1'000'000'000'000'000'000'000'000'000>;      // Since C++26 not supported
 typedef ratio<1, 1000000000000000000000000> yocto;  // not supported
 typedef ratio<1,    1000000000000000000000> zepto;  // not supported
 typedef ratio<1,       1000000000000000000> atto;
 typedef ratio<1,          1000000000000000> femto;
 typedef ratio<1,             1000000000000> pico;
 typedef ratio<1,                1000000000> nano;
 typedef ratio<1,                   1000000> micro;
 typedef ratio<1,                      1000> milli;
 typedef ratio<1,                       100> centi;
 typedef ratio<1,                        10> deci;
 typedef ratio<                       10, 1> deca;
 typedef ratio<                      100, 1> hecto;
 typedef ratio<                     1000, 1> kilo;
 typedef ratio<                  1000000, 1> mega;
 typedef ratio<               1000000000, 1> giga;
 typedef ratio<            1000000000000, 1> tera;
 typedef ratio<         1000000000000000, 1> peta;
 typedef ratio<      1000000000000000000, 1> exa;
 typedef ratio<   1000000000000000000000, 1> zetta;  // not supported
 typedef ratio<1000000000000000000000000, 1> yotta;  // not supported
+using ronna = ratio <1'000'000'000'000'000'000'000'000'000' 1>;      // Since C++26 not supported
+using quetta = ratio <1'000'000'000'000'000'000'000'000'000'000, 1>; // Since C++26 not supported
 
   // 20.11.5, ratio comparison
   template <class R1, class R2> inline constexpr bool ratio_equal_v
     = ratio_equal<R1, R2>::value;                                       // C++17
   template <class R1, class R2> inline constexpr bool ratio_not_equal_v
     = ratio_not_equal<R1, R2>::value;                                   // C++17
   template <class R1, class R2> inline constexpr bool ratio_less_v
     = ratio_less<R1, R2>::value;                                        // C++17

libcxx/include/version

 // # define __cpp_lib_bind_back                            202306L
 # undef  __cpp_lib_bind_front
 # define __cpp_lib_bind_front                           202306L
 // # define __cpp_lib_bitset                               202306L
 // # define __cpp_lib_copyable_function                    202306L
 // # define __cpp_lib_fstream_native_handle                202306L
 // # define __cpp_lib_function_ref                         202606L
 // # define __cpp_lib_hazard_pointer                       202306L
-// # define __cpp_lib_ratio                                202306L
+# define __cpp_lib_ratio                                202306L
 // # define __cpp_lib_rcu                                  202306L
 // # define __cpp_lib_smart_ptr_owner_equality             202306L
 // # define __cpp_lib_sstream_from_string_view             202306L
 // # define __cpp_lib_submdspan                            202306L
 // # define __cpp_lib_text_encoding                        202306L
 // # define __cpp_lib_within_lifetime                      202306L
 #endif
 
 // clang-format on
 
 #endif // _LIBCPP_VERSIONH

libcxx/test/std/language.support/support.limits/support.limits.general/ratio.version.compile.pass.cpp

 #elif TEST_STD_VER == 23
 
 # ifdef __cpp_lib_ratio
 #   error "__cpp_lib_ratio should not be defined before c++26"
 # endif
 
 #elif TEST_STD_VER > 23
 
-# if !defined(_LIBCPP_VERSION)
-#   ifndef __cpp_lib_ratio
-#     error "__cpp_lib_ratio should be defined in c++26"
-#   endif
-#   if __cpp_lib_ratio != 202306L
-#     error "__cpp_lib_ratio should have the value 202306L in c++26"
-#   endif
-# else // _LIBCPP_VERSION
-#   ifdef __cpp_lib_ratio
-#     error "__cpp_lib_ratio should not be defined because it is unimplemented in libc++!"
-#   endif
-# endif
+# ifndef __cpp_lib_ratio
+#   error "__cpp_lib_ratio should be defined in c++26"
+# endif
+# if __cpp_lib_ratio != 202306L
+#   error "__cpp_lib_ratio should have the value 202306L in c++26"
+# endif
 
 #endif // TEST_STD_VER > 23
 

libcxx/test/std/language.support/support.limits/support.limits.general/version.version.compile.pass.cpp

 #     error "__cpp_lib_ranges_zip should have the value 202110L in c++26"
 #   endif
 # else // _LIBCPP_VERSION
 #   ifdef __cpp_lib_ranges_zip
 #     error "__cpp_lib_ranges_zip should not be defined because it is unimplemented in libc++!"
 #   endif
 # endif
 
-# if !defined(_LIBCPP_VERSION)
-#   ifndef __cpp_lib_ratio
-#     error "__cpp_lib_ratio should be defined in c++26"
-#   endif
-#   if __cpp_lib_ratio != 202306L
-#     error "__cpp_lib_ratio should have the value 202306L in c++26"
-#   endif
-# else // _LIBCPP_VERSION
-#   ifdef __cpp_lib_ratio
-#     error "__cpp_lib_ratio should not be defined because it is unimplemented in libc++!"
-#   endif
-# endif
+# ifndef __cpp_lib_ratio
+#   error "__cpp_lib_ratio should be defined in c++26"
+# endif
+# if __cpp_lib_ratio != 202306L
+#   error "__cpp_lib_ratio should have the value 202306L in c++26"
+# endif
 
 # ifndef __cpp_lib_raw_memory_algorithms
 #   error "__cpp_lib_raw_memory_algorithms should be defined in c++26"
 # endif
 # if __cpp_lib_raw_memory_algorithms != 201606L
 #   error "__cpp_lib_raw_memory_algorithms should have the value 201606L in c++26"
 # endif
 

libcxx/utils/generate_feature_test_macro_components.py

for x in [
             "values": {"c++23": 202110},
             "headers": ["ranges", "tuple", "utility"],
             "unimplemented": True,
         },
         {
             "name": "__cpp_lib_ratio",
             "values": {"c++26": 202306}, # P2734R0 Adding the new SI prefixes
             "headers": ["ratio"],
-            "unimplemented": True,
         },
         {
             "name": "__cpp_lib_raw_memory_algorithms",
             "values": {"c++17": 201606},
             "headers": ["memory"],
         },
         {
             "name": "__cpp_lib_rcu",