dataclasses

I'm a big fan of @mhashemi's work in Python in general, even if I don't use Boltons personally. The discussion regarding inclusion in the stdlib is sensible, and I fully agree with @mhashemi's comments. See similar discussions, for instance, regarding dataclasses vs. attrs (https://github.com/ericvsmith/dataclasses/issues/19). Sometimes, however, it's a bit annoying when something that you think should be widely available isn't included in the stdlib. The cons of course are: - Fragmentation (several project pursuing similar objectives) - Not being able to use a powerful construct to simplify code in the stdlib itself (the stdlib can only depend on the stdlib). Regarding, for instance, functional programming, I maintain a list of interesting projects in this domain in Python: https://github.com/sfermigier/awesome-functional-python/blob...

The article doesn't discuss slots and default values. Here's the actual reference implementation for dataclasses where it's discussed: https://github.com/ericvsmith/dataclasses/issues/28 Your second solution works fine (and is what I'd referenced). For your first solution, I'd again redirect you to my statement "they don’t support __slots__ and default values" and the above link.

I love using attrs, like the idea of bringing something similar to the standard library, but strongly disagree with the dataclasses API. It treats untyped Python as a second class citizen. This is what I'd prefer from dataclasses import dataclass, field @dataclass class MyClass: x = field() but it produces an error because fields need to be declared with a type annotation. This is the GvR recommended way to get around it: @dataclass class MyClass: x: object You could use the typing.Any type instead of object, but then you need to import a whole typing library to use untyped dataclasses. I highly prefer the former code block. There's a big thread discussing the issue on python-dev somewhere. Also some discussion in https://github.com/ericvsmith/dataclasses/issues/2#issuecomm... Anyway, it's not a huge issue—attrs is gr

While 3.7 is not here, back-port: https://github.com/ericvsmith/dataclasses