Re: Default value of "preload" attribute

On Thu, 25 Mar 2010, Robert O'Callahan wrote:
> On Thu, Mar 25, 2010 at 12:51 PM, Ian Hickson <ian@hixie.ch> wrote:
> > On Thu, 25 Mar 2010, Robert O'Callahan wrote:
> > > The default value of "preload" is currently "auto".
> >
> > Actually the spec says the default is UA-defined. "auto" is only a 
> > suggestion.
> 
> I actually think that leaving the missing value default up to the UA is 
> a mistake. The difference between "auto" and "metadata" for user 
> experience is often going to be significant. I wonder if other 
> implementors actually want their missing value default to be "auto"?

Given that pretty much the entire attribute's handling is UA-defined, I 
really don't see much point in making the default defined. Certainly I 
don't think it makes sense to make the default be something that 
explicitly cannot be to download everything, since if that's what the user 
wants, that's what the user should get.

However I don't mind changing the suggestion. What do browsers generally 
default to? If most browsers default to metadata, there's not much point 
suggesting auto. :-)


> One more thing ... the resource fetch algorithm says that when 
> preload="metadata" UAs should stop loading after the first frame 
> (HAVE_CURRENT_DATA). Shouldn't that value be named "firstframe" (or 
> something else) then? It's pretty confusing to have preload="metadata" 
> not stop after the metadata has loaded.

Yeah, the name is mildly misleading. I considered "firstframe" but it 
didn't really seem in the style of the Web platform, insofar as the Web 
has a style. It's not really that confusing; it's not like authors are 
going to say "goodness, why is it that it downloads up to the first frame 
instead of stopping 512 bytes earlier at the end of the metadata?". In 
fact you could even argue that for many purposes (e.g. filling in the 
poster frame if poster="" isn't provided) the first frame is a kind of 
metadata anyway.

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

Received on Thursday, 25 March 2010 08:41:54 UTC