[whatwg] HTML5 Definition of week (section 2.4.5.6)

[Ian Hickson]

On Mon, 20 Jul 2009, David Singer wrote:
> At 10:45  +0000 19/07/09, Ian Hickson wrote:
> > On Fri, 3 Jul 2009, SJ Kissane wrote:
> > > 
> > >  I am concerned by the wording of this section. There are different
> > >  systems of week number -- as far as I can work out, this is the same as
> > >  ISO 8601 week numbering. But it nowhere explicitly says that.
> > > 
> > >  I think, the spec should have a normative reference to ISO 8601 for the
> > >  definition of week numbering. Then, if the spec wants to give an
> > >  informative recap of what ISO 8601 says, for the benefit of those who
> > >  don't have a copy (especially since it isn't free), that's fine. But I'm
> > >  worried, by inserting some complicated definition into the spec, does it
> > >  match exactly ISO 8601's definition? (I'm sure it does, but "are the
> > >  definitions the same?" is not immediately obvious from inspection.)
> > 
> > They are not the same. ISO8601 doesn't define how you parse a week string,
> > how you handle errors in such a string, and so forth. The numbers are
> > compatible, and a valid HTML5 week string is an ISO8601 week string
> > (though I don't know if the opposite is the case), but that's about it.
> > 
> > While we could have an non-normative reference, in practice, it wouldn't
> > add much, since (a) the HTML5 spec defines everything you might get from
> > ISO8601, and (b) we don't want to have implementors think "oh, it's the
> > same as ISO8601, I'll just use an ISO8601 date library", since such a
> > library might get the parsing details wrong in terms of what HTML5 says.
> 
> an informative note to that effect might be a good idea.

Done.

-- 
Ian Hickson               U+1047E                )\._.,--....,'``.    fL
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