otherprops syntax - should we specify?

Just wanted to start the discussion
on the list. For background, take a look at the conditional processing
topic in the current draft of the spec.

In the conditional processing section,
it says:

"Each attribute takes zero or more space-delimited
string values."

Now, this is fine for semantically grouped
values like those in the product or audience attributes, but is inadequate
for otherprops, which might contain multiple semantic groupings. For example,
otherprops might take parenthetical groupings of values as well as directly
contained values. 

Chris Wong pointed out that because
we haven't specified the syntax of otherprops in the past we could invalidate
some existing designs by specifying it now.

We might be able to address this concern
either by basing our design on the existing one if it passes muster, or
if there are multiple designs in use we could soften the wording from a
requirement to a recommendation in the case of otherprops. 

Otherwise I think we leave a hole in
the specification that could result in multiple incompatible implementations
of conditional processing code, and content that becomes tied to one implementation
or the other.

Michael Priestley