[Python-ideas] Null coalescing operator

[MRAB]

On 2016-09-10 18:44, Paul Moore wrote:
> On 10 September 2016 at 18:26, Guido van Rossum <guido at python.org> wrote:
>> IMO the key syntax is
>> simply one for accessing attributes returning None instead of raising
>> AttributeError, so that e.g. `foo?.bar?.baz` is roughly equivalent to
>> `foo.bar.baz if (foo is not None and foo.bar is not None) else None`,
>> except evaluating foo and foo.bar only once.
>
> If we're not looking to use all the other null-coalescing variants
> (?=, ?(), ...) - which is something I'm pleased about, as I do think
> that scattering that many ?'s about is likely to lead to ugly code -
> then it would probably be fine to just use ? for this operation, so
> we'd have foo?bar?baz rather than needing foo?.bar?.baz.
>
I think that's not as clear; the "?." at least looks like a form of 
attribute access.

It would also mean that it would be more difficult to add the other 
null-coalescing variants later, if the need arose.