Re: content mark-up: operators vs. relations?

> It is an error to enclose a relation in an element other than reln.

> But the example immediately following and some earlier examples show relns
> inside applys.

but a `reln' is not a `relation element' according to the text of the
spec. So you are supposed to use <reln/> to apply <lt/> to two values, but
if you want to combine two such relations with <and/> then you need to
<apply/> <and/>.

The plan is that this situation will be improved in MathML2, although
the details are not finalised.

The current best guess is that the restriction on not using <apply/>
with `relation' elements will be dropped and so you will be able to
uniformly use <apply/> (with reln being kept for largely historical


Follow-Ups: References: