[Python-Dev] PEP 457: Syntax For Positional-Only Parameters

[Benjamin Peterson]

2013/10/8 Ethan Furman <ethan at stoneleaf.us>:
> On 10/08/2013 08:09 PM, Benjamin Peterson wrote:
>>
>> 2013/10/8 Terry Reedy <tjreedy at udel.edu>:
>>>
>>> On 10/8/2013 9:31 PM, Benjamin Peterson wrote:
>>>>
>>>>
>>>> 2013/10/8 Larry Hastings <larry at hastings.org>:
>>>>>
>>>>>
>>>>> This PEP proposes a backwards-compatible syntax that should
>>>>> permit implementing any builtin in pure Python code.
>>>>
>>>>
>>>>
>>>> This is rather too strong. You can certainly implement them; you just
>>>> have to implement the argument parsing yourself. Python's
>>>> call/signature syntax is already extremely expressive, and resolving
>>>> call arguments to formal parameters is already a complicated (and
>>>> slow) process. Implementing functions with such strange argument
>>>> semantics is hardly common enough to justify the whole grouping syntax
>>>> proposed in this PEP. -1 to that. I think I can live with "/", but
>>>> YANGTNI still.
>>>
>>>
>>>
>>> I am for having a way to succintly properly describe the signature of C
>>> in
>>> the manual and docstrings and help output. As it is now, the only safe
>>> thing
>>> to do, without trial and exception, is to assume positional only unless
>>> one
>>> knows otherwise.
>>
>>
>> Having a nice syntax for the docs is quite different from implementing
>> it in the language.
>
>
> It would be nice, however, to have it implemented at some point.

Why? It's quite complex and hardly useful.


-- 
Regards,
Benjamin