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Re: [SG16] D1949R4 - Unicode Identifiers

From: Tom Honermann <tom_at_[hidden]>
Date: Wed, 27 May 2020 13:33:34 -0400
On 5/27/20 1:03 PM, Zach Laine via SG16 wrote:
> On Wed, May 27, 2020 at 12:01 PM Jens Maurer via SG16
> <sg16_at_[hidden]> wrote:
>> On 26/05/2020 22.51, Steve Downey via SG16 wrote:
>>> Find attached a draft of the UAX31 paper for discussion.
>>> Viewable at http://htmlpreview.github.io/?https://github.com/steve-downey/papers/blob/master/generated/p1949.html
>>> Source at https://github.com/steve-downey/papers/blob/master/p1949.md
>> I had asked earlier for some prose-text statement on the difficulty
>> of checking NFC.
>>
>> I can only find
>>
>> "Detection of un-normalized text is fairly straight-forward, and GCC 10 already produces a warning. Normalizing to NFC is not much more difficult."
>>
>> which is lacking a bit of depth.
>>
>> What exactly do I have to do to check for NFC? Check some bits in the code points?
>> Consult some Unicode tables? Something else?
> You have to look up each adjacent pair of code points in a table, and
> verify that they form a valid NFC sequence.

I think Jens' point is that the paper doesn't state that (and that it
should).

Tom.

>
> Zach

Received on 2020-05-27 12:36:42