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Subject: Re: [SG16-Unicode] Draft SG16 direction paper
From: Tom Honermann (tom_at_[hidden])
Date: 2018-10-10 22:38:36


On 10/10/2018 03:28 PM, keld_at_[hidden] wrote:
> Hi
>
> I got around to read the paper.

Great, thanks, Keld!

>
> Some questions:
>
> Do you really require Unicode/10646 for the new specs?

I'm assuming you are asking about the motivation for P1025R1
<http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1025r1.html>.
If not, please correct me.

Prior to P1025R1, the C++ standard did have a normative reference to ISO
10646, but it specifically named the 1993 version which predated
UTF-16.  This left us without formal definitions for UTF-16, UTF-32, and
surrogate code point despite use of those terms being present.

> Why not allow normal POSIX/C/C++ character types?

I'm afraid I don't understand the question.  Allow these types in what
context?

>
> Another point: It is not necessary to normalize strings to
> compare strings using locale aware string comparison.
> This is probably a little known fact.

Yes.  The questions about comparison in the paper are with regard to
whether a std::text type should have default comparison operators and,
if so, which comparison algorithm should be used for that default.  That
default could be based on canonical equivalence or language sensitive
collation, but that would be overkill in situations where a fast
lexicographical compare would suffice.

Tom.

>
> Best regards
> Keld
>
> On Wed, Oct 03, 2018 at 01:13:38AM -0400, Tom Honermann wrote:
>> Enclosed is a draft of an SG16 direction paper to be discussed at our
>> meeting tomorrow.  It's rough, but I think in sufficient shape for
>> discussion.
>>
>> If we manage to get through that paper, we'll discuss the paper Steve
>> just posted to our mailing list [1] and/or Markus' feedback paper [2].
>>
>> Tom.
>>
>> [1]: http://www.open-std.org/pipermail/unicode/2018-October/000144.html
>> [2]:
>> https://docs.google.com/document/d/1aI0mBcH-d3BLjs8NRHgGECbA320LGFgo-SrNJ6VnLKE/edit
>>
>
>> _______________________________________________
>> SG16 Unicode mailing list
>> Unicode_at_[hidden]
>> http://www.open-std.org/mailman/listinfo/unicode



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