Proposal: Syntax for attribute initialisation in __init__ methods

[Sam Ezeh]

I'll see if I can find out how positional only and keyword only
arguments are used in __init__ methods in the wild and I'll see if
there have been any other discussions talking about what this approach
could offer.

On Sun, 17 Apr 2022 at 02:54, dn <PythonList at danceswithmice.info> wrote:
>
> On 17/04/2022 09.20, Sam Ezeh wrote:
> >> Perhaps I'm missing the point, but what functionality or advantage(s)
> >> does this give, over data-classes?
> >
> > One advantage is maintaining control over the __init__ function without
> > having to write extra code to do so. In the linked discussion from
> > python-ideas, it was mentioned that keyword-only and positional-only
> > arguments can't be used with dataclasses [1].
> >
> >> Maybe Dataclasses are not being used as much as one might hope, but they
> >> are relatively new, and many Python-Masters simply carry-on constructing
> >> classes the way they have for years...
> >
> > I think one concern I have is that even if this is useful, it might
> > still fall to the same fate.
>
>
> Don't be discouraged by that - and that thread was not the first of such
> discussions! The way Python is being applied is continually changing...
>
> I'm not sure about the criticism of dataclasses though. Starting with
> 'explicit over implicit', once a parameter-list is more than two or
> three long, shouldn't we be using 'labels' in order to avoid (potential)
> confusion, ie keyword-parameters?
>
> This removes the order/sequence of arguments from the list of potential
> problems/gotchas one can fall into!
>
> In which case, I'm wondering just how often the criticism applies 'in
> real life'?
>
> So, now the question becomes: what are the cases/examples which
> require/desire improvement over the 'traditional' __init__ of
> attributes, and facilities offered through dataclasses?
> --
> Regards,
> =dn
> --
> https://mail.python.org/mailman/listinfo/python-list