On 4 July 2018 at 11:25, Steven D'Aprano <steve@pearwood.info> wrote:

On Wed, Jul 04, 2018 at 11:08:05AM +0100, Ivan Levkivskyi wrote:
> Replying to the question in subject, I think it would be better in
> collections as a class.
> Having it just as a function doesn't buy much, because one can do the same
> with three lines and a defaultdict.
> However, if this is a class it can support adding new elements, merge the
> groupeddicts, etc.

defaultdicts support adding new elements, and they have an update method
same as regular dicts :-)

Except that updating will not do what I want. Merging two groupeddicts is not just `one.update(other)`

Moreover, using just an update with regular dicts will do something bug-prone, it will add every group

from `other` as an element to the corresponding group in `one`.

Ivan