[whatwg] [WA1] 2.7.13: sub and sup
ian at hixie.ch
Mon Dec 10 20:33:05 PST 2007
On Sun, 28 Aug 2005, dolphinling wrote:
> I would like it if the section on sub and sup included text along these lines:
> | The semantics of sub and sup are weaker than those of elements in
> | some other languages, e.g. MathML's msup. Authors should when possible
> | use those other languages instead of sub or sup.
The spec currently has this as markup:
<p>Mathematical expressions often use subscripts and superscripts.
<!--Authors are encouraged to use MathML for marking up mathematics,
but authors may opt to use <code>sub</code> and <code>sup</code> if
detailed mathematical markup is not desired. <a
href="#refsMathML">[MathML]</a>--></p> <!-- XXX -->
The problem is that there's no point telling authors to use, say, MathML,
when in fact they can't (since only one browser supports it).
> Actually, I think the semantics of sub and sup are nonexistant
Clearly they're not completely non-existent, since this:
...are three very different things.
> but I think this allows authors to use then when needed (e.g. when they
> need IE6 support) while providing strong enough reinforcement of the
> fact that better, more meaningful ways exist. (And while avoiding
> avoiding arguments among us standardisers about whether or not they have
> semantics, because whether or not they do, they're inarguably weaker :-)
Well, what would you replace them with? The only form at MathML that has
any support in browsers is presentational MathML anyway, which isn't that
much better, "semantically".
> Also, a few more comments on the section. While MathML is obviously the
> best-known and probably most important language using sub/superscripts,
> I think it should be noted that others (e.g. ChemML) exist, even if not
> noted by name.
ChemML enjoys even less support...
> For me, saying "sub and sup" is much more natural than "sup and sub".
> I'm not sure why this is, but the HTML 4 spec has it sub first, too.
> Would you mind switching it to this way in WA1?
> And finally, "Authors are encouraged to use MathML for marking up
> mathematical, but authors may..." <-- I think you're missing a word in
Fixed (as noted above).
Ian Hickson U+1047E )\._.,--....,'``. fL
http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,.
Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
More information about the whatwg