Re: [ietf-822] What about doing more?

[Valdis Kl ē tnieks <[e-mail]>]

On Sun, 11 Oct 2020 05:07:18 -0700, Dave Crocker said:
> On 10/8/2020 6:35 PM, Ricardo Signes wrote:
> > The Unicode Emoji List is revised more or less annually.  This means 
> > that releasing software that validates this header against the contents 
> > of UTS #51 is liable to fall out of date.
>
> The RFC series come with an up-pointer reference mechanism for 
> replacement versions.  It appears that The Unicode Consortium does not. 
> I'd guess the best we can do is to have some generic language associated 
> with the reference that says "or a successor".

Yeah, that's probably the "least worst" way to solve that problem.

> > ...some system attempts to decode the
> > IDN, finds that it contains unallocated code points
>
> How about:
>
>     Reference to unallocated code points SHOULD NOT be treated as an 
> error; the associated bytes SHOULD be presented in numeric form.
>
> or some such?

"associated bytes SHOULD be presented with the system default method
for denoting an unallocated or undisplayable code point"

Pretty much everything on my laptop uses an empty rectangular box to display
a character that's not available in the current font or other similar issues. And
yes, "allocated but not available" code points *will* happen if your font doesn't
have the pixels  needed...

Plus, "numeric" is a poor choice.  We should specify  "U+hexbytes" if we're going
that route. Otherwise some bozo UI person is going to make it output 15712188
instead of U+EFBFBC

"system default method or U+ format" probably covers all the reasonable
bases.