Shane F. Carr

My commentary: 1. The aux key is the most important piece of the locale and therefore is the last thing that should undergo fallback 2. Extension keywords too are important...

Discuss with: - @Manishearth - @sffc - @robertbastian

- @robertbastian - Aux key should go last because it is usecase defined. Transliterator and datetime will use this differently. It's not considered fallback; aux keys should be ignored in...

We still need to discuss the part about Unicode extension keyword fallback priority. Discuss with: - @sffc - @robertbastian Optional: - @Manishearth

The rewriting of this code should incorporate the new CLDR 45 fallback rules. https://github.com/unicode-org/icu4x/pull/4782

Oof, the resolver was being too _smart_ before, and now it's biting us. This is in `tutorials-local` CI: ```rust error[E0283]: type annotations needed --> src/main.rs:16:24 | 16 | let result...

Adding @Manishearth as reviewer because of the resolver issue

> > I thought adding impls was supposed to always be semver safe. > > No, it's actually expected: In general Rust does not consider "you will need to disambiguate"...

Yet Another Reason™ to not use `Into` bounds on function parameters. (CC @zbraniecki @robertbastian who like to do this sometimes)

Looking at the code, I'm surprised that the resolver looks at `&3.into() as Into` and decides to infer a `FixedDecimal` as the intermediate type when there is nothing suggesting that....