Re: [idn] IDNA interoperability failures, once again

["Adam M. Costello" <idn.amc+0@nicemice.net.RemoveThisWord>]

"Eric A. Hall" <ehall@ehsco.com> wrote:

> Nowhere in your specification does it state that encoded and
> non-encoded views of a domain name should be provided.

IDNA section 6.1 says:

    Because name labels encoded as ACE name labels can be rendered
    either as the encoded ASCII characters or the proper decoded
    characters, the application MAY have an option for the user to
    select the preferred method of display;

If there is a demand for this ability, applications will tend to provide
it.

> Have you documented the use of i18n domain names in URLs somewhere?

IDNA.  It documents how to use IDNs anywhere you can use regular domain
names.

> In conjunction with a SeeAlso header field or a RFC822-style
> References header field, this would not only mean that I was now
> generating illegal header fields

I don't know what a SeeAlso header field is.  A References header field
contains a list of <word>s and <msg-id>s, which can be distinguished
syntactically because the <msg-id>s begin and end with angle brackets
while the <word>s do not.  If the mail program is IDNA-compliant, then
when it constructs the References field (or when it checks the field
that the user has suggested) it obeys IDNA section 3 requirement 1 and
makes sure that the <domain>s inside the <msg-id>s are ASCII-only (it
can apply ToASCII if needed).

AMC