[Python-Dev] Python 3.7: remove all private C functions from the Python C API?

[Victor Stinner]

Hi,

Currently, Python has 3 C API:

* python core API
* regular API: subset of the core API
* stable API (ABI?), the Py_LIMITED_API thing: subset of the regular API

For practical purpose, all functions are declared in Include/*.h.
Basically, Python exposes "everything". There are private functions
which are exported using PyAPI_FUNC(), whereas they should only be
used inside Python "core". Technically, I'm not sure that we can get
ride of PyAPI_FUNC() because the stdlib also has extensions which use
a few private functions.

For Python 3.7, I propose that we move all these private functions in
separated header files, maybe Include/private/ or Include/core/, and
not export them as part of the "regular API".

The risk is that too many C extensions rely on all these tiny
"private" functions. Maybe for performance. I don't know.

What do you think?

See also the issue #26900, "Exclude the private API from the stable API":
http://bugs.python.org/issue26900

Victor