Is there a way to implement the ** operator on a custom object

[Alan Bawden]

Chris Angelico <rosuav at gmail.com> writes:

   > On 08Feb2024 12:21, tony.flury at btinternet.com <tony.flury at btinternet.com> wrote:
   > >I know that mappings by default support the ** operator, to unpack the
   > >mapping into key word arguments.
   > >
   > >Has it been considered implementing a dunder method for the **
   > >operator so you could unpack an object into a key word argument, and
   > >the developer could choose which keywords would be generated (or could
   > >even generate 'virtual' attributes).

   I presume this is more like:

   obj = SomeObject()
   func(**obj)

   ie making the object behave in a dict-like way. I can't remember how
   this is implemented, but you can create the necessary methods to have
   your object produce whatever it likes.

All you need to do is subclass collections.abc.Mapping, and
implement __len__, __iter__, and __getitem__.  Pretty easy.

- Alan