[Python-Dev] Deprecating "instance method" class

[Jeroen Demeyer]

On 2019-04-05 15:13, Serhiy Storchaka wrote:
> It is easy to implement a function in C.

Why does it need to be a PyCFunction? You could put an actual method 
descriptor in the class. In other words, use PyDescr_NewMethod() instead 
of PyCFunction_New() + PyInstanceMethod_New(). It's probably going to be 
faster too since the instancemethod adds an unoptimized extra level of 
indirection.

> Yes, this is what I want to do. I did not do this only because
> implementing method-like functions which which do not belong to concrete
> class implemented in C is not convention.

Sure, you could implement separate methods like __gt__ in C, but that's 
still less efficient than just implementing a specific tp_richcompare 
for total_ordering and then having the usual wrapper descriptors for __gt__.