[Python-ideas] Keyword only argument on function call

[Jonathan Fine]

Steve Barnes suggested adding __params__, as in

>      def a_method(self, cr, uid, ids, values, context=None):
>        ...
>        params = {k:v for k,v in __params__ if k in parent.a_method.keys()}
>        # Possibly add some additional entries here!
>        super(self, parent).a_method(**params)


Steve D'Aprano commented

> In single-threaded code, there's no problem here:
>
>     A makes the first call;
>     the interpreter sets function.__params__ to A's arguments;
>     the function runs with A's arguments and returns;


I'm puzzled here. Steve B provided code fragment

    for k,v in __params__

while Steve D provided code fragment

    function.__params__

by which I think he meant in terms of Steve B's example

   a_method.__params__


Perhaps Steve D thought Steve B wrote

     def a_method(self, cr, uid, ids, values, context=None):
       ...
       params = {k:v
            for k,v in a_method.__params__   # Is this what Steve D
thought Steve B wrote?
            if k in parent.a_method.keys()
       }
       # Possibly add some additional entries here!
       super(self, parent).a_method(**params)

If Steve B had written this, then I would agree with Steve D's
comment. But as it is, I see no race condition problem, should
__params__ be properly implemented as a keyword identifier.

Steve D: Please clarify or explain you use of

    function.__params__

Perhaps it was a misunderstanding.

By the way: I've made a similar mistake, on this very thread. So I
hope no great shame is attached to such errors.

<quote>
https://mail.python.org/pipermail/python-ideas/2018-September/053224.html

Summary: I addressed the DEFINING problem. My mistake. Some rough
ideas for the CALLING problem.

Anders has kindly pointed out to me, off-list, that I solved the wrong
problem. His problem is CALLING the function fn, not DEFINING fn.
Thank you very much for this, Anders.
</quote>

-- 
Jonathan