Update README.rst

README.rst

@@ -29,8 +29,7 @@ Features
 * Safe `printf implementation
   <https://fmt.dev/latest/api.html#printf-formatting>`_ including
   the POSIX extension for positional arguments.
-* Implementation of the ISO C++ standards proposal `P0645
-  Text Formatting <https://fmt.dev/Text%20Formatting.html>`__.
+* Implementation of `C++20 std::format <https://fmt.dev/Text%20Formatting.html>`__.
 * Support for user-defined types.
 * High performance: faster than common standard library implementations of
   `printf <http://en.cppreference.com/w/cpp/io/c/fprintf>`_ and