That's a pretty good example... except that HTML5 already requires that browsers support SVG and MathML elements in HTML documents without any namespacing at all.
The other problem with adding namespaces to HTML for machine metadata is that HTML5 already supports arbitrary opaque content in attributes whose names begin with "data-". Sure, it doesn't solve the extensibility problem as thoroughly as namespaces would, but it takes a good bite out of Microsoft's use-cases, and maybe the 80% solution is Good Enough.
Comments
That's a pretty good example... except that HTML5 already requires that browsers support SVG and MathML elements in HTML documents without any namespacing at all.
The other problem with adding namespaces to HTML for machine metadata is that HTML5 already supports arbitrary opaque content in attributes whose names begin with "data-". Sure, it doesn't solve the extensibility problem as thoroughly as namespaces would, but it takes a good bite out of Microsoft's use-cases, and maybe the 80% solution is Good Enough.