[swift-evolution] [Proposal] Normalize Unicode Identifiers

[Joe Groff]

> On Jul 26, 2016, at 12:26 PM, Xiaodi Wu via swift-evolution <swift-evolution at swift.org> wrote:
> 
> +1. Even if it's too late for Swift 3, though, I'd argue that it's highly unlikely to be code-breaking in practice. Any existing code that would get tripped up by this normalization is arguably broken already.

I'm inclined to agree. To be paranoid about perfect compatibility, we could conceivably allow existing code with differently-normalized identifiers with a warning based on Swift version, but it's probably not worth it. It'd be interesting to data-mine Github or the iOS Swift Playgrounds app and see if this breaks any Swift 3 code in practice.

-Joe