[Python-ideas] Accepting multiple mappings as positional arguments to create dicts

[Sven R. Kunze]

I usually go with + only to find out that dict was something special 
here. ;-)
Then, I use .update only to find out, that it's in-place and I need to 
join more than two.
Then, I use some sort of dict comprehension or the dict constructor etc.

Naively, I would say + is what comes to mind easily. :D
Then, even sum(my_dicts) would work. ;-)


on-topic: Multiple arguments to dict(*my_dicts) just complements the 
alternative {**...} comprehension. So, it seems legit. +1


On 12.04.2018 21:32, Andrés Delfino wrote:
> There's a long thread about the subject: 
> https://mail.python.org/pipermail/python-ideas/2015-February/031748.html
>
> I suggest to avoid the matter altogether :)
>
> On Thu, Apr 12, 2018 at 4:15 PM, Mike Miller 
> <python-ideas at mgmiller.net <mailto:python-ideas at mgmiller.net>> wrote:
>
>     While we're on the subject, I've tried to add dicts a few times
>     over the years to get a new one but it doesn't work:
>
>         d3 = d1 + d2  # TypeError
>
>     Thinking a bit, set union is probably a better analogue, but it
>     doesn't work either:
>
>         d3 = d1 | d2  # TypeError
>
>     Where the last value of any duplicate keys should win.
>
>     -Mike
>
>
>
>     On 2018-04-12 06:46, Andrés Delfino wrote:
>
>         Extending the original idea, IMHO it would make sense for the
>         dict constructor to create a new dictionary not only from
>         several mappings, but mixing mappings and iterables too.
>
>         Consider this example:
>
>         x = [(1, 'one')]
>         y = {2: 'two'}
>
>         Now: {**dict(x), **y}
>         Proposed: dict(x, y)
>
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