On 06/11/2021 23.21, Hubert Tong wrote:
> On Sat, Nov 6, 2021 at 4:07 PM Jens Maurer <Jens.Maurer_at_[hidden] <mailto:Jens.Maurer_at_[hidden]>> wrote:
>
> On 06/11/2021 16.22, Hubert Tong via SG16 wrote:
> > Anyhow, if the intent really is to help only with the visual ambiguity problem, then it would be more consistent to allow /universal-character-name/s that encode to more than one code unit in multicharacter literals (because it's in a multicharacter literal already).
>
> If we use a UCN, we have no source code visual ambiguity
> (because a UCN is expressed in basic characters).
> Is that a correct understanding of the situation / motivation?
>
>
> Yes.
>
>
> I can't connect your parenthetical remark to that.
>
>
> The UCN does not itself contribute to the visual ambiguity of the character literal as being a single /c-char/.
>
>
>
> > With a focus on the visual ambiguity problem (thanks for reminding), the previous wording to limit /basic-c-char/s to the basic character set is more capable because lots of Unicode display shenanigans will get through the current formulation if the ordinary literal encoding is UCS-2 or UTF-16 (which is possible if CHAR_BIT is large enough).
>
> Do we have sufficient implementation experience / understanding of
> existing practice to estimate how much code will break if we
> restrict multi-character literals to the basic character set?
> (Note that neither @ or $ are in the basic character set.)
>
> (I'm all for restricting multi-character literals as much as possible,
> but we should probably avoid stepping on people's toes for non-portable
> features that don't really hurt anyone.)
>
>
> We could just restrict "problematic" Unicode characters?

Those are ones that take more than one code unit, I presume?

Jens