[ob] unbreak MI

[Nick Roberts]

 > > Generally, with a NULL pointer, or and address that can't be dereferenced,
 > > MI prints out the value field as value="".
 > 
 > If this is a requirement, could it be added to the manual?  I'd have
 > naively expected no value to not be printed.

That's exactly what does happen from the perspective of the front end: it
takes the null string and prints it, i.e., nothing.

I'm not sure what would be worthwhile to say and I never considered this
situation when writing the front end for Emacs; it just came out right.
Perhaps, however, I've just got used to the status quo, and you could ask
others (Ericsson?) if they find this behaviour surprising.

 > Your patch is OK.

Committed.  Thanks.

-- 
Nick                                           http://www.inet.net.nz/~nickrob