[swift-evolution] [Pitch] Adding accessibility specifiers to @available

[Ben Rimmington]

> On 22 Aug 2017, at 17:08, Tony Allevato wrote:
> 
> A few months ago (before Swift 5 chatter started), I pitched an idea to improve the use of @availability in third-party code by eliminating deprecation warnings in same-file references. We had some good discussion there about who needed same-file deprecation vs. same-module deprecation and so forth, and I was convinced that a better approach would be to allow @available to be enforced based on accessibility.

FYI

Excise "Accessibility" from the compiler:
<https://github.com/apple/swift/pull/11504>

> @jrose-apple (Jordan Rose) wrote:
> 
> "Accessibility" has a different meaning for app developers, so we've already deliberately excised it from our diagnostics in favor of terms like "access control" and "access level". Do the same in the compiler now that we aren't constantly pulling things into the release branch.
> 
> (This isn't exactly important, but we might as well clean it up.)