[Ur] Several patches and questions

[Edward Z. Yang]

Excerpts from Adam Chlipala's message of Mon Dec 31 21:51:43 +0800 2012:
> Ruling out children of tags that shouldn't have children is one thing 
> which might be worth addressing, but is that the only reason to support 
> registration of new singletons?  I mostly view the singletons list as 
> for compatibility with browsers that don't think in terms of XML, so 
> that it shouldn't be growing now that all the browsers are ready for 
> XHTML.  New tags will get proper XHTML support to begin with.
> 
> We could save a few characters here and there on pages by using </> 
> instead of <></>.  Is there a more compelling reason than that to make a 
> change to Ur/Web?

Aha, it looks like I misremembered the XHTML spec; <></> is permitted but
dis-recommended for BC reasons.  In that case, probably rounding out the rest
of the empty tags (base, meta, param, area, col--meta is the most important
thing) and not bothering with the empty syntax may be right.

Edward

(Unrelatedly, these days, XHTML is seeming more and more of a dinosaur.
For one thing, nearly no-one serves XHTML with the correct Content-Type,
and there's this HTML5 thing...)