- From: Mathew Marquis <mat@matmarquis.com>
- Date: Sat, 12 May 2012 10:49:36 -0400
- To: whatwg@whatwg.org
On May 12, 2012, at 10:36 AM, James Graham wrote: > > > On Sat, 12 May 2012, Mathew Marquis wrote: > >> While that information may be available at the time the img tag is parsed, I don’t believe it will be available at the time of prefetching — I’m happy to research this further and report back with citations. > > I am very confused about what you are claiming here. I have difficulty imagining any scheme that would make prefetching work worse with an attribute than with multiple elements. As Simon says there is a lot more that can go wrong in the multiple-element case because a single attribute can be processed atomically, but multiple elements can have all sorts of other junk between them that makes naieve processing (of a type likely to be used when prefetching) more likely to go wrong e.g. > > <picture> > <img src="foo"> > <script>document.write("</picture>")</script> > <source src="bar"> > </picture> > I think we can safely assume that any developer responsible for the above code likely won’t blame the element itself when it produces undesirable results. I assume such a pattern applies to the video and audio elements as well, and I’ve yet to see any developers declare them failures because they accidentally wrote a script that injects half a <marquee> tag in there. However, given a completely foreign and somewhat puzzling new syntax, I think it’s far more likely we’ll see the following: <img src="face-600-200@1.jpeg" alt="" set="face-600-200@1.jpeg 600w 1x, face-600-200@2.jpeg 600w 2x, face-icon.png 200w"> Become: <img src="face-600-200@1.jpeg" alt="" set="face-600-200@1.jpeg 600 1x, face-600-200@2.jpeg 600 2x, face-icon.png 200"> Or: <img src="face-600-200@1.jpeg" alt="" set="face-600-200@1.jpeg, 600w 1x face-600-200@2.jpeeg 600w 2x, face-icon.png 200w"> Regardless of how gracefully the above fail by comparison to a developer _purposefully injecting a closing tag into an element_, I’m confident this is a far more likely scenario and a “spot the differences” game very few developers will be excited to play.
Received on Saturday, 12 May 2012 14:50:08 UTC