<info> problems

[Mike Maxwell <maxwell@umiacs.umd.edu>]

In DocBook 5, there are apparently five different kinds of <info> 
elements, although none of them is distinguished by the tag name itself. 
 When we edit a <book> including as an immediate daughter this <info> 
element in XMLmind, we get an error if the <info> element in turn 
contains a <title> (or I guess a <subtitle>).

I *believe* (but am not certain) that this reflects a problem in the rng 
schema, not in XMLmind itself, which simply validates the doc using the 
standard rng schema.  My guess is that it's using the 
db.titleforbidden.info definition of <info> at the book level, rather 
than the db.info definition.

I don't however understand how the schema validation chooses which 
'info' definition to use.  A similar issue of multiple definitions 
arises with HTML vs. CALS <table>s, but if I understand correctly, the 
validator chooses which of these definitions of <table> to use based on 
the daughters of a particular <table> element.  Whereas in this case, it 
seems to be choosing which definition of <info> to use *despite* the 
daughters.

Over here
   http://docbook.org/docs/howto/
I see footnote b of table 1 says
   RELAX NG grammar enforces exclusivity of several elements.
   For example if you have title inside info then it is not
   allowed to have another title outside info.
In our case, the <book> element has only the single <title>, inside the 
<info> element.  However, the <chapter>s do have <title>s which are not 
inside <info> element.  Does the above footnote mean that if you use an 
<info><title>...</title></info> structure (i.e. db.info) as a daughter 
of <book>, the <chapter>s canNOT have a <title> as an immediate 
daughter?  And hence the only way for a <chapter> to have a <title> is 
for it to use a db.titlereq.info element (since db.info cannot appear as 
a daughter of <chapter>).  That seems rather odd, not to mention 
confusing...

Why this proliferation of different kinds of <info> elements?
--
	Mike Maxwell
	maxwell@umiacs.umd.edu
	"My definition of an interesting universe is
	one that has the capacity to study itself."
        --Stephen Eastmond