element markup in attributes

["Simon St.Laurent" <simonstl@simonstl.com>]

I hesitate a bit in raising questions about HTML5 here, mostly because 
of concerns that the violence of that conversation will enter the 
discussion here.  Nonetheless, this list is the best place I know of to 
discuss markup best practices, and seems like the right place to ask the 
question.

The iframe element has always been a tricky critter, but in HTML5 it's 
picked up a srcdoc attribute which "gives the content of the page that 
the nested browsing context is to contain."  This allows the 
construction of short documents in an iframe context without requiring a 
separate HTTP request through the src attribute.

Details can be found here:

<http://dev.w3.org/html5/spec-author-view/the-iframe-element.html>
<http://www.whatwg.org/specs/web-apps/current-work/multipage/the-iframe-element.html>

So what does this look like? Here are three examples from those specs.

-----------------------------------
<iframe seamless sandbox="allow-same-origin" srcdoc="<p>did you get a 
cover picture yet?"></iframe>

<iframe seamless sandbox="allow-same-origin" srcdoc="<p>Yeah, you can 
see it <a href=&quot;/gallery?mode=cover&amp;amp;page=1&quot;>in my 
gallery</a>."></iframe>

<iframe seamless sandbox="allow-same-origin" srcdoc="<p>hey that's 
earl's table.
<p>you should get earl&amp;amp;me on the next cover."></iframe>
-----------------------------------

What do folks think?  Is this reasonable, given the use case, or is this 
pushing too hard on attributes and escaping?

I wonder if just letting iframe have child content would make more 
sense, but I suspect that raises more compatibility problems with older 
browsers.

Thanks,
-- 
Simon St.Laurent
http://simonstl.com/