In vanilla Python to create a class which, when initiated, would also initiate another class I would use __init__(self):
class SomeClass: __init__(self, token: str): self.token = token client = WebClient(auth=self.token)But in attrs, I can't do this. The following yields an error because it is passing a _CountringAttr object, not the resolved string.
@attr.s()
class SomeClass: token: str = attr.ib() client = WebClient(auth=token)What is the "right" way of accomplishing this?
1 Answer
You can either use a default:
@attr.define
class SomeClass: token: str client: WebClient = attr.field() # needed! attr.ib works too @client.default def _client_factory(self): return WebClient(self.token)or __attrs_post_init__:
@attr.define
class SomeClass: token: str client: WebClient = attr.field(init=False) def __attrs_post_init__(self): self.client = WebClient(self.token)P.S. I'm using the modern attrs APIs to make them more known. Check out if you want to know more.
