[Python-ideas] Unpacking a dict

[Nikolaus Rath]

On May 26 2016, Paul Moore <p.f.moore-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org> wrote:
> On 26 May 2016 at 18:55, Ethan Furman <ethan-gcWI5d7PMXnvaiG9KC9N7Q at public.gmane.org> wrote:
>> With the simple syntax that I could live with, a real example could be:
>>
>>   {active_id, active_ids, active_model} = context
>>
>> or
>>
>>   {partner_id, product_id, ship_to, product_ids} = values
>
> The behaviour of using the names of the variables from the LHS to
> introspect the value on the RHS is, to me, extremely magical and
> unlike anything I've seen in any other language. I don't think it sits
> well in Python, even though it is certainly a very readable idiom for
> the sort of unpacking we're talking about here.

Very true. But as someone else already said (I can't find the email
right now), we have a different construct that everyone is familiar with
and that's easily adapted for this situation:

from dict context import active_id, active_ids, active_model

or more general:

"from dict"  <expr> "import" <identifier list>

Everyone knows that "from .. import .." modifies the local namespace. We
just have to extend it to work not just on modules, but also on
dictionaries.


Best,
-Nikolaus

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