Automatically create index of commands

[davidw@dedasys.com (David N. Welton)]

Hi, I'm attempting something a little bit more complicated with my
docbook work...  My application is growing, and new commands are being
added.  Where a page with all the commands listed was once enough, it
now seems that an index based on concepts would be useful to users,
something like this:

http://tmml.sourceforge.net/doc/tcl/index.html

At the moment, I have a series of commands described like:

    <variablelist>
      <varlistentry>
	<term>
	  <cmdsynopsis>
	    <command>
	      var
	    </command>
	    <group choice="req">
	      <arg>get</arg>
	      <arg>list</arg>
	      <arg>exists</arg>
	      <arg>number</arg>
	      <arg>all</arg>
	    </group>
	  </cmdsynopsis>
	</term>
	<listitem>
	  <para>
	    The <command>var</command> command retrieves information
	    about GET or POST variables sent to the script via client
	    request.  It treats both GET and POST variables the same,
	    regardless of their origin.  Note that there are two
	    additional forms of <command>var</command>:
	    <command>var_qs</command> and <command>var_post</command>.
	    These two restrict the retrieval of information to
	    parameters arriving via the querystring
	    (?foo=bar&amp;bee=bop) or POSTing, respectively.
	  </para>

I would like to have an index of all the commands in the list, and I'm
wondering if there is any way to do that without some very heavy XSL
hacking - i.e. something provided for in standard DocBook.

Incidentally, I suppose it also means that I need some markup to
describe where each command should be indexed, and a 'short
description' for the index.  Suggestions for those?

Thanks in advance for any ideas...  I've wallowed through the docs
some, but don't see anything that seems to be the right fit.
Hopefully, I just missed it or didn't quite see how to use it...

Thankyou,
-- 
David N. Welton
   Consulting: http://www.dedasys.com/
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