Request: Add retired tag "eml" to the IANA registry

[Randy Presuhn]

Hi -

> From: "Michael(tm) Smith" <mike at w3.org>
> To: "Phillips, Addison" <addison at amazon.com>
> Cc: <ietf-languages at alvestrand.no>
> Sent: Friday, December 11, 2009 12:39 AM
> Subject: Re: Request: Add retired tag "eml" to the IANA registry
...
> So lacking any likelihood of those retired tags actually getting
> into the IANA subtag registry, I'd suggest it'd at least be nice
> to have -- in whatever IETF or IANA document where it would be
> most appropriate -- some statement of guidance to developers
> saying, "Tools that check and report on instances of usage of
> language subtags SHOULD use both the data in the IANA subtag
> registry and the available data about IS0-639-3 retired codes."
...

I strongly disagree.  The ISO standards served as a source of codes,
but by design there is no need for tools to consult the ISO documents.
The case you're pursuing is one of trying to figure out where a user who
has failed to use the registry might have mistakenly come up with an
erroneous subtag.  There may be applications where this might be
a worthwhile undertaking, but that's far outside the realm of standardization,
in my opinion.  If a user's entry of "eml" is a typographical error, rather
than a conscious decision to use a data source other than the registry,
telling the user about "retired codes" might not be terribly helpful.

The handling of similar cases has always been motivated by the desire
to provide compatibility with earlier versions of the BCP, rather than all
the non-conformant stuff folks might have done "out there". If  "eml" had
been a valid subtag at some time in the lifetime of BCP 47, then adding
it (and those other codes) might make sense.  But since it's never been
registered, no one ever had any business using it as a language subtag
in the first place.

Randy