Type errors using Annotated[some_type, ...] as type argument

[tdsmith]

Calls of the form

with svcs.Registry() as reg:
    reg.register_value(Annotated[int, "my_int"], 42)

are recommended by the svcs docs for the case of multiple factories for the same type (here, int).

Pyright has recently started complaining about this, with a (slightly unhelpful) message of the form error: Argument of type "type[int]" cannot be assigned to parameter "svc_type" of type "type" in function "register_value" (reportArgumentType). (gist)

Some interesting related conversations came up in a search:
microsoft/pyright#7238 (Typing issue with Annotated)
https://discuss.python.org/t/is-annotated-compatible-with-type-t/43898 (Is Annotated compatible with type[T]?) (spoiler: "no")
python/typing-council#18 (Typing spec change for Annotated special form)

I think this means that the svcs docs should not recommend the Annotated construct. I think the alternative is weakening the declared type of svc_type to Any, which doesn't seem great. Does that sound right to you?

[hynek]

Oh cool our Pyright config made it pointless for our test, because this is still passing:

https://github.com/hynek/svcs/blob/main/tests/typing/core.py#L144-L152

---

This is unfortunate but I guess the only way forward is to stop recommending Annotated? We might add a side-note I guess.

[hynek]

"fixed" in #92