I believe this note is in opposition to languages that originated
contemporaneously with C but that do not distinguish between upper and
lower case. Fortran and Cobol, for example, do not, but also restrict the
identifier set to ASCII equivalent letters.
I think it is clear enough, since it is a Note, but is certainly a
candidate for reevaluation in another pass through lex bringing all of this
out of 1970s technical lexicon.

On Thu, Jun 4, 2020 at 6:33 PM Corentin Jabot via SG16 <
sg16_at_[hidden]> wrote:

> LGTM
>
> Nitpick:
>
> [ Note: Upper- and lower-case letters are considered different for all
> identifiers. – end note ]
>
> Not all characters with case mapping are letters.
> I don't know if it matters much if we are going to use better terms in the
> future
> Overall, I'm not sure that the note clarifies anything?
>
> On Fri, 5 Jun 2020 at 00:15, Steve Downey via SG16 <sg16_at_[hidden]>
> wrote:
>
>> Posted as Draft at https://isocpp.org/files/papers/D1949R4.html
>> If there are no objections, I will update to P later this evening and
>> post to the EWG list.
>>
>> Diff:
>>
>> https://github.com/steve-downey/papers/commit/a5a928b12b5664de57d5c0d8a9ca6ba4200d168b
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