RE: Updated Versioning Strategies document

Noah,

I think you're right that the problem area is wider than markup languages, but I
agree with Ashok that all artificial languages is too wide a scope. I've
commented that programming languages don't fit in well with the Finding: source
code usually doesn't have a version identifier, 'ignore unknown' is most often
not a desideratum in source code (see my Python 3 example in [1]) , etc.

I think the difference is more or less between languages which contain data
(including text) and languages which contain instructions. Admittedly this is a
vague criterion, since there are abundant examples of languages which cross this
line, but still, it seems the general direction to take.

But it's certainly true that the Finding does (mostly) apply to non-markup
data-oriented languages.

Regards,

Marc

[1] http://lists.w3.org/Archives/Public/www-tag/2008Apr/0082.html

| Ashok Malhotra writes:
| 
| > Thus, the heart of the finding is section 5. So, I feel we 
| should fix 
| > the earlier parts and state clearly our focus on markup 
| languages and 
| > their problems.
| 
| Well, this seems to be an area where some of us have differing 
| inclinations, and I'm afraid Dave will feel pulled in different 
| directions.  Dave's original work several years ago focussed 
| mainly on XML 
| in particular.  Some of us felt that it was important to set out the 
| general principles in terms that are more general than markup 
| languages 
| specifically.  Forwards and backwards compatibility, and how 
| one models 
| the interpretation of new language features by older 
| processors, seems to 
| be a foundation that one needs independent of whether the new 
| features are 
| realized as markup or in other forms.   Also, in practice, 
| markup-based 
| languages have lots of content that's not explicitly marked 
| up, such as 
| the contents of XML attributes and text elements.  The rules for 
| "versioning" these sublangages tend to be very similar to the 
| versioning 
| of documents in non-markup languages.   Thus, discussing only the 
| evolution of the markup itself really doesn't address the problem in 
| general, even for languages that are markup-based. Finally, I 
| think the 
| finding needs to reflect the intentions of the TAG as a 
| whole, and at this 
| point it's the more general analysis that the TAG has spent 
| most time on. 
| I suspect Dave would have been happy enough if we had done a more 
| markup-specific finding, but I think we will do a better 
| service to the 
| community if we can set out some of the more fundamental issues in 
| versioning.
| 
| Noah
| 
| --------------------------------------
| Noah Mendelsohn 
| IBM Corporation
| One Rogers Street
| Cambridge, MA 02142
| 1-617-693-4036
| --------------------------------------
| 
| 
| 
| 
| 
| 
| 
| 
| ashok malhotra <ashok.malhotra@oracle.com>
| Sent by: www-tag-request@w3.org
| 04/13/2008 03:54 PM
| Please respond to ashok.malhotra
|  
|         To:     orchard@pacificspirit.com
|         cc:     www-tag@w3.org, (bcc: Noah Mendelsohn/Cambridge/IBM)
|         Subject:        Re: Updated Versioning Strategies document
| 
| 
| 
| Dave:
| My action was to review only sections 2 and 4 but I ended up 
| reading the 
| entire document in fair detail.
| 
| My initial reaction was surprise at the scope of the document. You 
| address versioning of all (artificial) languages. With such a broad 
| scope it's difficult to make sharp recommendations. Thus, the 
| first part 
| of the finding reads like a tutorial on versioning. But then I got to 
| section 5, which is focused on markup languages and their 
| problems i.e. 
| using existing software (browsers) with new versions of the 
| language and 
| the document got much more focused and useful.
| 
| Thus, the heart of the finding is section 5. So, I feel we should fix 
| the earlier parts and state clearly our focus on markup languages and 
| their problems.
| 
| Specific Editorial Comments
| 
| Abstract:
| 
| "Separate documents contain the terminology definitions and 
| XML language 
| specific discussion". Please add pointers.
| 
| 1. Introduction
| 
| 1. The language should be extensible i.e. . (few words here)
| 
| 2. " . text of a language ." I don't like this. Seems to talk 
| about the 
| documentation. Perhaps you mean "statements of a language" or 
| "sentences 
| in the language"
| 
| 3. " .. a given language version should define a set of compatible 
| future version identifiers." Hard to do since I don't know 
| what future 
| versions of the language will contain.
| 
| 1.2 Kinds of Languages
| 
| Bug in reference under bullet 3.
| 
| 2.1 Why Have a Strategy?
| 
| " . there are many messages that don't use any features of the new 
| version or perhaps it is appropriate to simply ignore components that 
| are not recognized."
| 
| You have discussed only language text so far. Where do messages and 
| components come in?
| 
| "Often, what is needed is some sort of middle ground solution." What 
| might such a solution look like?
| 
| Remainder of 2 and 4. You give examples of RSS and HTML but other 
| examples of use/misuse of version numbers and other strategy would be 
| really great! I realize this requires a great deal of work.
| 
| 5. Java did remove features by marking them as 
| 'deprecated'and providing 
| compiler warnings and then removing them in later versions.
| 
| At the end of the section you say "select one of the following 3 
| alternatives" but there are only 2 alternatives. I prefer the second.
| 
| 5.1 The SOAP MustUnderstand is not a language feature. It's a 
| directive 
| to the processor.
| 
| "Choosing to ignore the container node only helped HTML considerably, 
| but there are some elements who's children also should be ignored for 
| rendering, particularly the /Script/ element." I'm not sure what you 
| meant to say. Is this sentence missing a "not".
| 
| 7. I would remove the last sentence. It seems to have a typo as well.
| 
| All the best, Ashok
| 
| 
| 
| Dave Orchard wrote:
| > Based upon feedback from Noah, the TAG's Feb f2f, and phone 
| > discussions with Noah.
| > http://www.w3.org/2001/tag/doc/versioning-compatibility-strategies
| > 
| http://www.w3.org/2001/tag/doc/versioning-compatibility-strate
| gies-20080328.html
| 
| > These are now ready for review by Ashok, Dan, Noah, Norm, and Raman 
| > per our agreements at the Vancouver F2F in 
| > http://www.w3.org/2008/02/26-tagmem-minutes#ActionSummary
| > Cheers,
| > Dave
| 
| 
| -- 
| All the best, Ashok
| 
| 
| 
| 
|

Received on Monday, 14 April 2008 15:59:00 UTC