[swift-evolution] Prohibit invisible characters in identifier names

[João Pinheiro]

> On 23 Jun 2016, at 20:43, Xiaodi Wu <xiaodi.wu at gmail.com> wrote:
> That's cool, although my preferred solution would be more closely aligned with UAX #31: overtly disallow the glyphs in Table 4 (instead of ignoring them) except in the specific scenarios for ZWJ and ZWNJ identified in UAX #31, then afterwards internally represent the identifier as its NFC-normalized string.

Explicitly disallowing them was my initial idea, but I think it would end up being a confusing error for users to encounter. Ignoring the invisible characters and leaving it up to a linter to remove them is less likely to cause confusion for users.

I'll be sure to describe the alternative of explicitly prohibiting them in the proposal though.

Sincerely,
João Pinheiro