Re: Combining characters (was: Re: [idn] hostname historyhell)

["Eric A. Hall" <ehall@ehsco.com>]

liana Ye wrote:

> I'd like to propose a more specific layering of IDN symbols:
> 
>  From the top where the user input buffer offers:
> 
>  Layer 3:  label seperators and label order normalizing
> 
>  Layer 2: Bidi label normalizing (or verticle label normalizing)

What is the current display order for unstructured and structured data in
right-to-left display systems? Does unstructured data ("the files are on
server1") typically flow RTL, while URLs and other structured data display
as LTR?

It seems that these questions are for the structured data groups to handle
when they decide on an output presentation mechanism. But if URLs and
other structured types will display RTL then that may affect us as well
(your Layer 3 label ordering in particular).

>  Layer 1.5: diacritic marks and combining symbol normalizing
> 
>  Layer 1:  IDN identifier matching or whatever comes out
>                of [nameprep].
> 
> The reason for Layer 1.5 is that these symbols can be
> treated in a similar way with Han characters depending on
> what architecture we end up with, and what ACE will be
> our focus.

-- 
Eric A. Hall                                        http://www.ehsco.com/
Internet Core Protocols          http://www.oreilly.com/catalog/coreprot/