levels and versions [was Re: Modules and levels in a specification]

At 05:51 PM 8/6/02 +0100, you wrote:

>On 2002.08.06 17:06 Dominique Hazaël-Massieux wrote:
>>Le mar 06/08/2002 à 17:52, Andrew Thackrah a écrit :
>>>   re SpecGL modules/levels/profiles
>>>   I'm not clear on the difference between a level and a spec version -
>>are
>>>   they different?
>>Yes, they are. Level implies (as the spec GL describes it) a hierarchy
>>of features: anything available in DOM Level 1 is also available in DOM
>>Level 2. DOM Level 2 completes DOM Level 1, but is backward compatible
>>with it.
>>Versionning implies no such promises regarding backward compatibility,
>>nor regarding hierarchical inclusions. Basically, different versions are
>>not supposed to have anything in common, except probably the target of
>>the spec (that is, as I understand it).
>
>  Thanks for explaining this.
>  In my previous email I imaged what HTTP would be like post specGL - 
> currently
>  the version number is a very important identifier of conformance (the 
> only one?)
>  How will future specs deal with versions and levels? Will the version 
> number still be used or will it be subsumed into a level?

I don't have answers to those specifics.  Thinking out loud...

I think it is useful to clearly distinguish the concept of specification 
version number and functional level, even if they are often identical or 
squashed together into a single number in practice.  Unfortunately, there 
is no consistency in current specifications, nor is there even (to my 
knowledge) a clear concept or requirement of "version number" in W3C 
Recs.  Probably the status-date subtitle of the specification is the only 
common *required* thread for specification version number, amongst W3C 
specs, e.g.

QA Framework: Specification Guidelines
W3C Working Draft 15 May 2002

"XML 1.0 Second Edition" is something like a version number (but with 
embedded reference to functional level) -- a maintenance revision of XML 
"level 1".  "CSS 2.1" is something like a version number (ditto).

Btw, have a look at this (non-required) bit in the Manual of Style:

http://www.w3.org/2001/06/manual/#title

Now that I've said all of this, I think we (QA) have some things to liaise 
with Comm Team about!

Note that we address this (spec versions) a little bit in OpsGL [1] and 
also in the editors-draft TestGL.  Operations and TS framework must plan 
for and accommodate versioning/errata.  Those requirements would, in my 
opinion, apply equally to "historical" functional levels -- functional 
levels that are defined progressively after the first Edition.

-Lofton.

[1] http://www.w3.org/QA/WG/2002/framework-20020507/qaframe-ops#b2ab3d375

Received on Tuesday, 6 August 2002 19:30:22 UTC