On 10/24/2018 5:30 AM, Anders Hovmöller wrote:
Well that seems super unfortunate. You can opt out of the auto generate constructor and do it yourself:
@dataclass(init=False) class Foo: foo: str bar: str = None baz: str
def __init__(self, *, foo, bar = None, baz): self.foo = foo self.bar = bar self.baz = baz
Foo(foo='a', bar='b', baz='c')
but this seems to take away from the utility of dataclasses. One could imagine there being a new argument to @dataclass that would make this work. Something like:
@dataclass(init_kwargs_only=True) class Foo: foo: str bar: str = None baz: str
where you would then get an auto generated constructor like with keyword only arguments. Personally I think this should have been the default, but it's at least a nice addition now.
https://bugs.python.org/issue33129
I definitely wouldn't want this to be the default. And as you say, it's too late anyway.
I haven't decided how the interaction of per-field and whole class versions of keyword-only should operate.
Eric