Tag Archives: dataclasses

Dataclasses coming in Python 3.7

I’ve been loving my time writing in Python. I started with 3.4 I think, and every release has brought something new and useful to the table. All the speed and async improvements are great, but the thing that I loved most in Python 3.6 was the new f string formatting. Removing boilerplate and providing the simplest easiest path just makes every task easier.  Less code on a page means fewer places to make mistakes. So it’s much better to see simple than complex code.

foo = 'bar'
# this is so clear and direct
message = f'Meet me at the {foo}'
# versus
message = 'Meet me at the {location}'.format(location = foo)

In 3.7, I’m excited about dataclasses. It’s like the attrs library – just a simple place to store data where you don’t have to re-implement all the standard dunder methods (__repr__, __str__, __eq__ etc). Adding a dataclass decorator and a list of the fields gives you a class with a standard constructor and all the other bells and whistles. The more you can use the standard library to accomplish high level concepts without having to type more code and write more bugs, the better. It’s coming in Python 3.7, but you can use dataclasses today with Python 3.6 using this backport on github – totally same functionality.

I’ve been playing around with using them here.