Guido van Rossum wrote:
>
> Do we want to support d[**kwargs]? It can be done, alternatively we could
> just ask the user to write the __getitem__/__setitem__ call explicitly.
> I think we should say no to d[*args], because that will just become
> d[(args)], with awkward questions around what if args == (1,). Maybe then
> for consistency we needn't bother with **kwargs, though the case for that
> is definitely stronger.
> Sorry for telegraphing this -- I am way past my bedtime but looking at this
> from the C API POV definitely made some things clear to me. I'm probably
> posting this in the wrong thread -- I can't keep up (and GMail splits
> threads after 100 messages, which doesn't help).
I hope I understood correctly because Mailman eats the * signs for formatting,
but is it possible (and desirable) to have a different behaviour for *args and
index when there is only one positional value ? Using "index" would keep the
current behaviour : pass a tuple except when there is only one value, in that
case the value is passes as-is. On the other hand if *args is passed in the
signature, it always gets the positional arguments in a tuple, whatever their
number. It would avoid the classical isinstance(index, tuple) check. Here are
some examples of what I mean:
# Usual signature
class Simple:
def __getitem__(self, index):
print(index)
simple = Simple()
simple[0] # 0
simple[0, 1] # (0, 1)
# This is valid python, but useless ?
class Star:
def __getitem__(self, *index):
print(index)
star = Star()
star[0] # (0,)
star[0, 1] # ((0, 1),)
# I propose this breaking change
class NewStar:
def __getitem__(self, *index):
print(index)
star = Star()
star[0] # (0,)
star[0, 1] # (0, 1)
This is theoretically a breaking change, but who in his right mind would write
such a Star class with the current python ?
Any thoughts ?
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