[Python-Dev] Experiment an opt-in new C API for Python? (leave current API unchanged)

[Antoine Pitrou]

On Fri, 16 Nov 2018 09:46:36 -0800
Brett Cannon <brett at python.org> wrote:
> 
> I think part of the challenge here (and I believe it has been brought up
> elsewhere) is no one knows what kind of API is necessary for some faster VM
> other than PyPy. To me, the only C API that would could potentially start
> working toward and promoting **today** is one which is stripped to its bare
> bones and worst mirrors Python syntax. For instance, I have seen
> PyTuple_GET_ITEM() brought up a couple of times. But that's not syntax in
> Python, so I wouldn't feel comfortable including that in a simplified API.
> You really only need attribute access and object calling to make object
> indexing work, although for simplicity I can see wanting to provide an
> indexing API.

If the C API only provides Python-level semantics, then it will
roughly have the speed of pure Python (modulo bytecode execution).

There are important use cases for the C API where it is desired to have
fast type-specific access to Python objects such as tuples, ints,
strings, etc.  This is relied upon by modules such as _json and _pickle,
and third-party extensions as well.

Regards

Antoine.