RE: ambiguity in BNF: no non-numeric TLDs?

[moved over to the IRI list from the URI list]

At 18:29 03/11/13 -0800, Michel Suignard wrote:

>I guess we need to make sure we have similar text in IRI.

I have just added it to the internal draft
(see http://www.w3.org/International/iri-edit)

Regards,    Martin.


>BTW Roy, when can we expect your revised RFC2396 text to move ahead? IRI
>has a dependency on it.
>
>Michel
>
>-----Original Message-----
>From: Roy T. Fielding [mailto:fielding@apache.org]
>
> > Can we assume that TLDs will be non-numeric?
>
>Yes, but we can't assume that the last domain is a TLD.
>
> > It looks to me that the BNF is ambiguous between hostname and IPv4
> > addresses because the BNF for hostname doesn't rule out
> >   nnn.nnn.nnn.nnn
>
>Yes, it says that in the text describing the rule:
>
>     The production for host is ambiguous because it does not completely
>     distinguish between an IPv4address and a hostname.  Again, the
>     "first-match-wins" algorithm applies: If host matches the production
>     for IPv4address, then it should be considered an IPv4 address
>literal
>     and not a hostname.
>
>All of our attempts to disambiguate within the grammar itself did not
>work because, without a trailing ".", there is no way to know which is
>the TLD.
>
>....Roy

Received on Wednesday, 26 November 2003 16:11:15 UTC