[whatwg] Parsing RFC3339 constructs

[Ian Hickson]

On Fri, 5 Jun 2009, Julian Reschke wrote:
> Ian Hickson wrote:
> > On Fri, 5 Jun 2009, Julian Reschke wrote:
> > > Ian Hickson wrote:
> > > > > Michael(tm) Smith wrote:
> > > > > > 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.
> > > So why make it different from RFC 3339?
> > 
> > Limiting the syntax to the simplest possible syntax was an intentional 
> > design choice intended to ease the burden on implementors and authors. 
> > In practice, pretty much every time we've made syntax 
> > case-insensitive, we've ended up having trouble because of it.
> 
> If this was a totally new syntax, I would agree.
> 
> But as something based on ISO8601 (and thereby also RFC 3339) it appears 
> to be a bad idea to make it less compatible just for that reason.

We've seriously simplified the ISO-8601 syntax in many more ways than just 
this. This was a conscious design decision.


> > The HTML5 spec defines exactly how to parse dates. Implementors are 
> > required to implement what the spec describes, so reusing libraries is 
> > implicitly not likely to be useful here. RFC3339 isn't even a 
> > particularly important one in the grand scheme of things (ISO8601 
> > comes to mind as a much higher-profile example).
> 
> I think it's unfortunate that HTML5 doesn't allow using an off-the-shelf 
> parser. But if it doesn't, and the temptation *will* be there to use 
> them, I'd recommend stating it very clearly.

Done.

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