On Tue, 12 Jul 2022, 18:05 Steve Jorgensen, <stevecjor@gmail.com> wrote:
Chris Angelico wrote:
> On Mon, 11 Jul 2022 at 03:54, Steve Jorgensen stevecjor@gmail.com wrote:
> > David Mertz, Ph.D. wrote:
> > I've seen this thread, and also wondered why anyone could EVER want a
> > dataclass that is an enum.  Nothing I've seen in the thread gives me any
> > hint about that, really.
> > On Sun, Jul 10, 2022 at 7:44 AM Barry Scott barry@barrys-emacs.org wrote:
> > On 9 Jul 2022, at 22:53, Steve Jorgensen stevecjor@gmail.com wrote:
> > I don't think that dataclasses have the limited set of intended uses
> > that you are interpreting them as having. To me, the fact that they can be
> > frozen makes them a good fit with Enum.
> > Please quote the email that you are replying to.
> > It is usually considered a code smell to have a class that is two or more
> > things.
> > This seems to be what you are trying to do.
> > How can one class be a set of fields and also the enum for one of its own
> > fields?
> > I do not understand why this is resonable.
> > Barry
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> > Sorry, I don't know how I communicated that I was trying to have one class be a set of fields and also the enum for one of its own fields.
> > I'm really just wanting to have each member of the enum be an instance of a frozen dataclass. If an of the dataclass fields were of an enum type, then it would presumably not be for the same enum. In my example, none of the fields of the dataclass contains an enum. One contains a string, and the other contains an int.
> > Just throwing an idea out there, but would it work better to have an
> enum-namedtuple instead?
> ChrisA

The only benefit I can think of for namedtuple vs a dataclass is compactness in memory, but the number of members of an enum is typically very small. I think the extra flexibility of a dataclass makes more desirable for this purpose.

The ability to unpack a namedtuple as an iterable is considered to be a great advantage the dataclass has over the named tuple because changing the number of members is a backwards incompatible change for namedtuple.

No reason in principle why a frozen dataclass should be less memory efficient than a namedtuple (?).

Michael