Consider using ITS "Locale Filter" instead of data-lang

[fsasaki]

Looking at the data-lang attribute the functionality seems identical to ITS "Locale Filter"

http://www.w3.org/TR/its20/#LocaleFilter

One should consider replacing data-lang with the standardized "Locale Filter" mechanism. This would be relatively easy:

1. at the top of https://github.com/w3c/clreq/blob/gh-pages/index.html add its-locale-filter-list="*" its-locale-filter-type="exclude"

2. replace all data-lang attributes with an its-locale-filter-list attribute. Its value is the same like for data-lang

3. replace in
   https://github.com/w3c/clreq/blob/gh-pages/script.js
   and in the CSS selectors all selectors for data-lang with a selector for its-locale-filter-list

Note that locale-filter is also understood by the w3c validator, so your document will keep to be valid, see this example

https://validator.w3.org/nu/?doc=http%3A%2F%2Fwww.w3.org%2FTR%2Fits20%2Fexamples%2Fhtml5%2FEX-locale-filter-local-html5-1.html

[r12a]

we don't actually need step 1, so it comes down to replacing all occurences of data-lang with its-locale-filter-list, which is an ITS defined name.

the downside is that it takes 2.5 times as long to type the attribute name for a content author, and since these attributes come in pairs, that's 5x the typing for each chunk of data labelled. Plus it makes the code marginally harder to read. In reality, ITS only defines data categories, and the actual names of attributes in the implementation don't have to be the same, just behave in the same way (so eg. in HTML we use the translate attribute rather than the its-translate attribute). That's less of a problem if we are copy-pasting.

but i guess it makes sense to use the same attribute name as in the ITS standard. One advantage being that it is clearer to people why this attribute is not the same as using the lang attribute, another is that it shows that we are using ITS concepts. (Note also that its-locale-filter-list validates.)

i guess we could try it, and if it's too long we could revert back to data-lang, or even data-locale.

[fsasaki]

I had assumed that this would now be implemented at
http://www.w3.org/TR/2015/WD-clreq-20150723/
but that does not seem to be the case. Was this a timing issue with the working draft publication?

[r12a]

i'm waiting for opinions from the group

i'm a little worried about the length of its-locale-filter-list. I'm inclined to think that it will reduce the readability of the source in github diffs and become a pain for manual editing, especially as we are about to add a third 'language' to the document (Simplified Chinese). I think we can certainly say, however, that data-lang represents a local instantiation of the locale filter data category.

[fsasaki]

Strange - I understood during our 1:1 call this week that you would move forward with its-locale-filter-list.
Keeping data-lang would be a pitty in terms of "dog fooding". We develop ITS2, reviewed by the i18n group, with no complains about attribute length. And then it comes to adoption the length concerns come up?
About "we can certainly say, however, that data-lang represents a local instantiation of the locale filter data category.": this does not help if you don't have a mapping between data-lang and the its-locale-filter-list. You can achieve that mapping via a rules files in the HTML "head" element:
<script type=application/its+xml>
<its:rules version="2.0" xmlns:its="http://www.w3.org/2005/11/its" its:version="2.0">
<its:localeFilterRule selector="//@[@data-lang='zh']" localeFilterList="zh"/>
<its:localeFilterRule selector="//@[@data-lang='en']" localeFilterList="en"/>
</its:rules>
</script>
This solution is not preferred because people will continue to use proprietary attributes.

[ysavourel]

I tend to agree with Felix.

Using the ITS attribute allows ITS processors to understand the file without having to do any mapping, and after all it is just following the W3C's own recommendation.

It's also a case different from translate, where the ITS specification does use the native HTML attribute (there is no its-translate).

[DavidFatDavidF]

The mapping through script is an afterthought and would have to be used if the right thing could not be done upfront.
I don't think that the argument about the length of the attribute will hold. Who edits totally manually nowadays? Every decent editor will autocomplete the attribute name.
+1 for dog fooding, why reinvent the wheel?

[xfq]

Can we close this issue now?

[r12a]

Ok to close from my pov.

[r12a]

Perhaps we should add that we are closing the issue because we implemented the proposal - replacing data-lang with its-locale-filter-list throughout.

[xfq]

OK. Closing.