[whatwg] Parsing RFC3339 constructs

[Ian Hickson]

On Mon, 27 Apr 2009, Julian Reschke wrote:
> Michael(tm) Smith wrote:
> > Ian Hickson <ian at hixie.ch>, 2009-04-25 05:35 +0000:
> >> On Fri, 2 Jan 2009, Asbj?rn Ulsberg wrote:
> >>> Reading the spec, I have to wonder: Does HTML5 need to specify as 
> >>> much as it does inline? Can't more of it be referenced to ISO 8601 
> >>> or even better; RFC 3339? I really fancy how Atom (RFC 4287) has 
> >>> defined date constructs: 
> >>> <http://www.atompub.org/rfc4287.html#date.constructs> Does not RFC 
> >>> 3339 defined date and time in a satisfactory manner to use directly 
> >>> in HTML5?
> >> The problem isn't so much the syntax definitions as the parsing 
> >> definitions. We need very specific parsing rules; it's not clear that 
> >> there is anything to refer to that does the job we need here.
> > 
> > It seems pretty clear that there isn't anything else to refer to for 
> > the date/time parsing rules -- but to me at least, specifying those 
> > rules seems orthogonal to specifying the date/time syntax, and I would 
> > think the syntax could just be defined by making reference to the 
> > productions[1] in RFC 3339 (instead of completely redefining them), 
> > while stating any exceptions.
> > 
> > [1] http://tools.ietf.org/html/rfc3339#section-5.6
> > 
> > I think the exceptions might just amount to:
> > 
> >   - the literal letters T and Z must be uppercase
> 
> Any technical reason why they have to?

Not really. We just need a separator.


> >   - a year must be four or more digits, and must be greater that zero
> 
> "a year must be four or more digits" -- sounds like an alternative 
> format that an additional RFC, updating RFC 3339 could specify.
> 
> "must be greater that zero" -- that's not syntax :-)
> 
> So yes, I think referring to RFC 3339, even if it's just a narrative 
> mention, would be good.

Why?


> Ian replied:
> > I don't understand what that would gain us.
> 
> It would help people understand what the difference to RFC 3339 is.

Why is that important or desirable? It seems that comparisons to other 
specs would be better placed in other documents. HTML5 doesn't even 
describe how it differs from its previous version (HTML4), why would it 
include descriptions of differences from otherwise unrelated RFCs?

-- 
Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'