On Fri, Feb 2, 2018 at 7:38 AM, Elvis Pranskevichus <elpr...@gmail.com>
> On Friday, February 2, 2018 10:08:43 AM EST Eric V. Smith wrote:
> > However, I don't feel very strongly about this. As I've said, I expect
> > the use cases for hash=True to be very, very rare.
> Why do you think that the requirement to make a dataclass hashable is a
> "very, very rare" requirement?
I think what's rare is wanting hashability without it being frozen.
> Just put yourself in the shoes of an average Python developer. You try
> to put a dataclass in a set, you get a TypeError. Your immediate
> reaction is to add "hash=True". Things appear to work.
agreed, the easy and obvious way should be to make it frozen -- if it's
hard to make it hashable and not frozen, then that's good.
But it is nice to have the __hash__ generated more you.... so maybe a flag
for "unfrozen_hashable" -- really klunky, but if that is a rare need, then
there you go.
If either hash or frozen is specified, it become both frozen and hashable.
If both are specified, then it does what the user is asking for.
Christopher Barker, Ph.D.
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