[swift-evolution] Pitch: Renaming CharacterSet to UnicodeScalarSet

[Ben Rimmington]

> On 28 Sep 2016, at 22:27, Erica Sadun wrote:
> 
> Why not rename `CharacterSet` to `UnicodeScalarSe`t, and update the initializers
> to reflect they're being initialized from the unicode scalars in strings and ranges?

I agree, but `UnicodeScalarSet` was rejected during the SE-0069 discussion:

<https://lists.swift.org/pipermail/swift-evolution/Week-of-Mon-20160425/015685.html>

-- Ben