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

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

"Eric A. Hall" wrote:

> The specific concern I had is already addressed in nameprep so there
> is no need for the exception.

What I am concerned with is the use of domain name which consist entirely
of punctuation, or in this case, which consist entirely of combining
marks. These represent a rules problem with the principles behind the
"safe-set". EG, we forbid domain names like ````````.com using U+0060, but
````````.com may be legal if the combining character U+0300 is used
instead.

I get lost in the shrubbery of specs, so can somebody tell me whether or
not this is a valid concern? I can't tell for certain what happens at the
end of nameprep with such a label.

If this is a problem, a solution might be to change the prohibition
against leading hyphen to a prohibition against leading hyphen and
combining characters.

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