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

[Benjamin Peterson]

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.



-- 
Regards,
Benjamin