where is APT::Default-Release documented?

["Daniel B." <REMOVEdanielTHIS@fgm.com>]

I'm having trouble getting APT::Default-Release to work.

Where is the documentation for it (in Sarge)?


The apt.conf(5) manual page sees to be where it should be documented
(e.g., in its section "The APT Group").  However, that manual page
doesn't mention it, anywhere.

The aptitude(8) manual page mentions APT::Default-Release, but only
to define something else in terms of it.

/usr/share/aptitude/README has only the same mention as aptitude(8).

/usr/share/doc/apt/examples/configure-index.gz contains an example,
but only a blank one, and no documentation.


So where is APT::Default-Release documented?

(What exactly does it do?  How can I see the difference it makes
without proceeding all the way with installing something?  For
example, change should I see in aptitude as I'm browsing packages or
if I partially select packages for installing (but before I confirm
and proceed with installing them)?)

Thanks.

Daniel