Subject: [Ltru] Definition of "grandfathered" considered lame

From: John Cowan <[email-masked]>
Date: Wed, 3 Jan 2007 17:24:52 -0500

In the ABNF in 4646bis-02, a Language-Tag (the root production) can be
a langtag, a privateuse, or a grandfathered.  But a grandfathered can
be a langtag or an irregular.  Consequently, the grammar is technically
ambiguous.

I propose that the Language-Tag production be changed to refer to
irregular directly rather than grandfathered.  The grandfathered
production needs to be kept because there is a reference to it in 3.1.2.

On the editorial side, the term "well-formed tag" is not really defined
anywhere.  It should be defined in one place and then used.  This would
be improved by not talking about "well-formed processors", but rather
about "non-validating processors", which is what is meant.

-- 
A rabbi whose congregation doesn't want         John Cowan
to drive him out of town isn't a rabbi,         http://www.ccil.org/~cowan
and a rabbi who lets them do it                 [email-masked]
isn't a man.    --Jewish saying

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From: Addison Phillips <[email-masked]>
Date: Wed, 03 Jan 2007 14:55:52 -0800

> production needs to be kept because there is a reference to it in 3.1.2.

I appreciate the point, yet I'm reluctant to make the change. I think it 
useful "self-commentary" to have 'grandfathered' appear in the 
Language-Tag production.

A better alternative would be:

- List both the regular and irregular sets. If my count is correct, the 
'regular' list has only 11 items in it in the 4646bis era. We can 
separately note that all of these items match the langtag production, 
which is what makes them 'regular'.

> about "non-validating processors", which is what is meant.

Not quite. There are *three* classes of conformance (two defined, and 
one undefined): validating, well-formed, and "everything else".

I agree that referencing "well-formed" in the ANBF is a bit out of 
whack, since we were careful to make "well-formed" and "validating" 
classes of conformance elsewhere. But the "well-formed tag" thing is 
problematic if we really mean the langtag production and not the 
Language-Tag production. This can be cleaned up by making the change I 
propose above and then referencing Language-Tag as synonymous with 
"well-formed".

Addison

-- 
Addison Phillips
Globalization Architect -- Yahoo! Inc.

Internationalization is an architecture.
It is not a feature.

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From: John Cowan <[email-masked]>
Date: Wed, 3 Jan 2007 18:27:33 -0500

> which is what makes them 'regular'.

The irregular set can't shrink, though.  The regular set can, if
we register subtags like boont.  (I tried, but Michael refused.)
What's more, it doesn't solve the problem I'm complaining about, which
is that some tags will be able to match the ABNF is more than one way.

> classes of conformance elsewhere.

Actually not.  Look at 2.2.6 bullet 3, and 2.2.8 graf 1, and the
first requirement of validating processors in 2.2.9, and 4.4 bullet 1,
and the example in 4.4.

> But the "well-formed tag" thing is problematic if we really mean the
> langtag production and not the Language-Tag production. This can be
> cleaned up by making the change I propose above and then referencing
> Language-Tag as synonymous with "well-formed".

I agree; "well-formed" should mean "matches the ABNF" and nothing else.
That way, non-validating processors MUST check that the tag is well-formed
and SHOULD check that there are no duplicate singletons.

-- 
John Cowan      http://www.ccil.org/~cowan      [email-masked]
Be yourself.  Especially do not feign a working knowledge of RDF where
no such knowledge exists.  Neither be cynical about RELAX NG; for in
the face of all aridity and disenchantment in the world of markup,
James Clark is as perennial as the grass.  --DeXiderata, Sean McGrath

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From: "Mark Davis" <[email-masked]>
Date: Wed, 3 Jan 2007 17:33:09 -0800

> and SHOULD check that there are no duplicate singletons.

Agreed

--

-- 
Mark