On Sat, Oct 31, 2020 at 08:24:04AM +0000, Barry Scott wrote:
> > On 31 Oct 2020, at 06:35, Steven D'Aprano <[email protected]> wrote:
> >
> > I think we can promise that:
> >
> > * if the mapping on the right has missing keys, no assignments occur;
> >
> > * if the mapping on the right has extra keys, and there is no double
> > star target to capture the extras, then no assignments occur;
>
> Why must I always handle all keys in the dictionary?
You don't. Use a double-star target to capture the excess, then ignore
it. This is similar to sequence unpacking:
spam, eggs, *who_cares = sequence
{'spam': spam, 'eggs', eggs, **who_cares} = mapping
will collect any excess items into `who_cares`. In the first case, it
will be a list; in the second, it will be a dict.
Barry:
> {'myitem': self.myitem, **other_kwds} = kwds
Indeed.
--
Steve
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