On Sat, Apr 30, 2022 at 11:54:47PM -0700, Christopher Barker wrote:
On Sat, Apr 30, 2022 at 6:40 PM Steven D'Aprano <steve@pearwood.info> wrote:
On Sat, Apr 23, 2022 at 12:11:07PM -0700, Christopher Barker wrote:
Absolutely. However, this is not an "all Classes" question.
Isn't it? I thought this was a proposal to allow any class to partake in the dataclass autoassignment feature.
no -- it's about only a small part of that.
How so? Dataclasses support autoassignment. This proposes to allow **all classes** (including non-dataclasses) to also support autoassignment. So can you pleae clarify your meaning. To me, this does look like an "all Classes" question. What am I missing?
I don't think of dataclasses as "mutable namedtuples with defaults" at all. What do you think of them as?
I answered that in the next line, that you quote.
Perhaps your answer isn't as clear as you think it is. See below.
But do think they are for classes that are primarily about storing a defined set of data.
Ah, mutable named tuples, with or without defaults? :-)
well, no. - the key is that you can add other methods to them, and produce all sort of varyingly complex functionality. I have done that myself.
Named tuples support all of that too. One of the reasons I have not glommed onto dataclasses is that for my purposes, they don't seem to add much that named tuples didn't already give us. * Record- or struct-like named fields? Check. * Automatic equality? Check. * Nice repr? Check. * Can add arbitrary methods and override existing methods? Check. Perhaps named tuples offer *too much**: * Instances of tuple; * Equality with other tuples; and maybe dataclasses offer some features I haven't needed yet, but it seems to me that named tuples and dataclasses are two solutions to the same problem: how to create a record with named fields.
Or possibly records/structs.
nope, nope, and nope.
Okay, I really have no idea what you think dataclasses are, if you don't think of them as something like an object-oriented kind of record or struct (a class with named data fields). You even define them in terms of storing a defined set of data, except you clearly don't mean a set in the mathematical meaning of an unordered collection (i.e. set()). A set of data is another term for a record. So I don't understand what you think dataclasses are, if you vehemently deny that they are records (not just one nope, but three). And since I don't understand your concept of dataclasses, I don't know how to treat your position in this discussion. Should I treat it as mainstream, or idiosyncratic? Right now, it seems pretty idiosyncratic. Maybe that's because I don't understand you. See below.
But anyway, the rest of my post was the real point, and we're busy arguing semantics here.
Well yes, because if we don't agree on semantics, we cannot possibly communicate. Semantics is the **meaning of our words and concepts**. If we don't agree on what those words mean, then how do we understand each other? I've never understood people who seem to prefer to talk past one another with misunderstanding after misunderstanding rather than "argue semantics" and clarify precisely what they mean. -- Steve