[Python-Dev] PEP 579 and PEP 580: refactoring C functions and methods

[Stefan Behnel]

INADA Naoki schrieb am 07.07.2018 um 06:10:
> How often "custom method type" are used?
> 
> I thought Cython use it by default.
> But when I read code generated by Cython, I can't find it.
> It uses normal PyMethodDef and tp_methods.
> 
> I found CyFunction in Cython repository, but I can't find
> how to use it.  Cython document doesn't explain any information
> about it.

Its usage is disabled by default because of some of the problems that
Jeroen addresses in his PEP(s).

You can enable Cython's own function type by setting the compiler directive
"binding=True", e.g. from your setup.py or in a comment at the very top of
your source file:

    # cython: binding=True

The directive name "binding" stems from the fact that CyFunctions bind as
methods when put into classes, but it's really misleading these days
because the main advantage is that it makes Cython compiled functions look
and behave much more like Python functions, including introspection etc.

Stefan