Re: rfc4646. Some analysis code

On 07/11/06, John Cowan <cowan@ccil.org> wrote:

> Excellent!

Thanks John.
TDD makes itself felt again :-)
>
> > I couldn't make much sense of  granfathered. I'll try and add it
> > in if someone would be kind enough to explain it.
>
> You should ignore the "grandfathered" production in the ABNF altogether.
> It will be replaced in the next RFC (temporarily called "RFC 4646bis")
> with the following production:
>
> irregular     = "en-GB-oed" / "i-ami" / "i-bnn" / "i-default"
>               / "i-enochian" / "i-hak" / "i-klingon" / "i-lux"
>               / "i-mingo" / "i-navajo" / "i-pwn" / "i-tao"
>               / "i-tay" / "i-tsu" / "sgn-BE-fr" / "sgn-BE-nl"
>               / "sgn-CH-de"
>
> Your code should simply check if a tag is case-insensitively equal to
> any of those 17 strings, and if so, declare it well-formed without further
> investigation.  This list is permanently fixed, so it is safe to freeze
> it into code.

No problem.... but how does it fit in with the
   langtag       = (language
                    ["-" script]
                    ["-" region]
                    *("-" variant)
                    *("-" extension)

grouping? You make it sound like an alternate? is that right?


>
> "Grandfathered" is a semantic concept (the meaning of the tag cannot be
> deduced from its parts); "irregular" a syntactic one (the tag cannot be
> parsed into parts using the regular parsing algorithms).  All irregular
> tags are grandfathered, but not all grandfathered tags are irregular.
> Unfortunately this distinction was not clarified until after 4646 was
> published.

Mmmm. I won't pretend to understand that! I guess the discussion
was more than the resulting text :-)

One more if I may.

Same topic.

 grandfathered = 1*3ALPHA 1*2("-" (2*8alphanum))
                   ; grandfathered registration
                   ; Note: i is the only singleton
                   ; that starts a grandfathered tag

Why wasn't it
        i 1*2ALPHA ......

Any particular reason?


regards

-- 
Dave Pawson
XSLT XSL-FO FAQ.
http://www.dpawson.co.uk

Received on Tuesday, 7 November 2006 19:31:53 UTC