gh-133678: Document C API third party tools (#134526)

Co-authored-by: Petr Viktorin <encukou@gmail.com>
Co-authored-by: Steve Dower <steve.dower@python.org>

Doc/c-api/intro.rst

@@ -838,3 +838,41 @@ after every statement run by the interpreter.)
 
 Please refer to :file:`Misc/SpecialBuilds.txt` in the Python source distribution
 for more detailed information.
+
+
+.. _c-api-tools:
+
+Recommended third party tools
+=============================
+
+The following third party tools offer both simpler and more sophisticated
+approaches to creating C, C++ and Rust extensions for Python:
+
+* `Cython <https://cython.org/>`_
+* `cffi <https://cffi.readthedocs.io>`_
+* `HPy <https://hpyproject.org/>`_
+* `nanobind <https://github.com/wjakob/nanobind>`_ (C++)
+* `Numba <https://numba.pydata.org/>`_
+* `pybind11 <https://pybind11.readthedocs.io/>`_ (C++)
+* `PyO3 <https://pyo3.rs/>`_ (Rust)
+* `SWIG <https://www.swig.org>`_
+
+Using tools such as these can help avoid writing code that is tightly bound to
+a particular version of CPython, avoid reference counting errors, and focus
+more on your own code than on using the CPython API. In general, new versions
+of Python can be supported by updating the tool, and your code will often use
+newer and more efficient APIs automatically. Some tools also support compiling
+for other implementations of Python from a single set of sources.
+
+These projects are not supported by the same people who maintain Python, and
+issues need to be raised with the projects directly. Remember to check that the
+project is still maintained and supported, as the list above may become
+outdated.
+
+.. seealso::
+
+   `Python Packaging User Guide: Binary Extensions <https://packaging.python.org/guides/packaging-binary-extensions/>`_
+      The Python Packaging User Guide not only covers several available
+      tools that simplify the creation of binary extensions, but also
+      discusses the various reasons why creating an extension module may be
+      desirable in the first place.

Doc/extending/index.rst

@@ -26,19 +26,9 @@ Recommended third party tools
 =============================
 
 This guide only covers the basic tools for creating extensions provided
-as part of this version of CPython. Third party tools like
+as part of this version of CPython. Some :ref:`third party tools
-`Cython <https://cython.org/>`_, `cffi <https://cffi.readthedocs.io>`_,
+<c-api-tools>` offer both simpler and more sophisticated approaches to creating
-`SWIG <https://www.swig.org>`_ and `Numba <https://numba.pydata.org/>`_
+C and C++ extensions for Python.
-offer both simpler and more sophisticated approaches to creating C and C++
-extensions for Python.
-
-.. seealso::
-
-   `Python Packaging User Guide: Binary Extensions <https://packaging.python.org/guides/packaging-binary-extensions/>`_
-      The Python Packaging User Guide not only covers several available
-      tools that simplify the creation of binary extensions, but also
-      discusses the various reasons why creating an extension module may be
-      desirable in the first place.
 
 
 Creating extensions without third party tools

Doc/faq/extending.rst

@@ -37,24 +37,9 @@ Writing C is hard; are there any alternatives?
 ----------------------------------------------
 
 There are a number of alternatives to writing your own C extensions, depending
-on what you're trying to do.
+on what you're trying to do. :ref:`Recommended third party tools <c-api-tools>`
-
+offer both simpler and more sophisticated approaches to creating C and C++
-.. XXX make sure these all work
+extensions for Python.
-
-`Cython <https://cython.org>`_ and its relative `Pyrex
-<https://www.csse.canterbury.ac.nz/greg.ewing/python/Pyrex/>`_ are compilers
-that accept a slightly modified form of Python and generate the corresponding
-C code.  Cython and Pyrex make it possible to write an extension without having
-to learn Python's C API.
-
-If you need to interface to some C or C++ library for which no Python extension
-currently exists, you can try wrapping the library's data types and functions
-with a tool such as `SWIG <https://www.swig.org>`_.  `SIP
-<https://github.com/Python-SIP/sip>`__, `CXX
-<https://cxx.sourceforge.net/>`_ `Boost
-<https://www.boost.org/libs/python/doc/index.html>`_, or `Weave
-<https://github.com/scipy/weave>`_ are also
-alternatives for wrapping C++ libraries.
 
 
 How can I execute arbitrary Python statements from C?

Doc/howto/cporting.rst

@@ -14,13 +14,11 @@ We recommend the following resources for porting extension modules to Python 3:
   module.
 * The `Porting guide`_ from the *py3c* project provides opinionated
   suggestions with supporting code.
-* The `Cython`_ and `CFFI`_ libraries offer abstractions over
+* :ref:`Recommended third party tools <c-api-tools>` offer abstractions over
-  Python's C API.
+  the Python's C API.
   Extensions generally need to be re-written to use one of them,
   but the library then handles differences between various Python
   versions and implementations.
 
 .. _Migrating C extensions: http://python3porting.com/cextensions.html
 .. _Porting guide: https://py3c.readthedocs.io/en/latest/guide.html
-.. _Cython: https://cython.org/
-.. _CFFI: https://cffi.readthedocs.io/en/latest/