Re: &foo= in attribute values (and why defining conformance matters)

On Mon, 15 Jun 2009, Simon Pieters wrote:
> On Sun, 14 Jun 2009 21:25:39 +0200, Ian Hickson <ian@hixie.ch> wrote:
> > > It might still be reasonable to change the parsing rules to make the 
> > > above case less surprising:
> > > 
> > > > >   3. Tweak the parsing rules so that = is treated the same as 
> > > > > 0-9a-zA-Z.
> > > 
> > > It would be different form what IE does, but I would be surprised if 
> > > Web compat requires the IE behavior here.
> > 
> > I'd really like to not risk changes to the parsing rules in this area. 
> > It took a lot of careful study to get to where we are now, and without 
> > repeating that work, I'd be very reluctant to experiment.
> 
> Data: 
> http://philip.html5.org/data/entities-without-semicolon-followed-by-equals.txt
> 
> The ones below are those that would be affected by this change. This is 
> 50 occurrences out of 425K pages.
> 
> As far as I can tell, all of these seem to expect the literal text 
> treatment rather than the entity treatment.

I only looked at a few, but of those some where text/plain documents (and 
so irrelevant), some were script blocks (and so unaffected), some were 
cases of &amp= where it was clear that &amp; was intended (with no = at 
all) and where the result wouldn't be technically correct either way, but 
where things seemed to work in practice the way they are now, and some 
were cases where it was clear that what was written wouldn't work as 
intended (eg. &GT=) but where in practice the results wouldn't differ 
visibly if we changed it (i.e. it's unclear if the server-side is working 
around the error in some way we don't know about).

I'm very reluctant to change this. This is exactly the kind of thing where 
we could cause subtle compatibility errors, and where a change would mean 
a gratuitous change relative to deployed browsers.

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

Received on Saturday, 11 July 2009 01:03:07 UTC