Add From for int types by clarfonthey · Pull Request #50554 · rust-lang/rust (original) (raw)

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fn try_result_ok() -> Result<u8, u8> { let val = Ok(1)?; Ok(val) }

Ok(x)? for Result<_, u8> (as well as variations like return Err(u8::from(unimplemented!()));) sound like an edge case for me - I don't think realistically anyone would write code like this. This can be written as x, and I think this inference failure is not a practical issue. The test here could be changed to use a type other than u8, for example fn try_result_ok() -> Result<u8, bool>.

Additionally, according to https://github.com/rust-lang/rfcs/blob/master/text/1105-api-evolution.md, this would be a minor change.