[dpkg wishlist] new search features?

[Xan <DXpublica@telefonica.net>]

Hi,

I'm a final user of Debian (desktop user). Recently, I think that it's 
necessary that dpkg allows to search packages like this way:

dpkg -l "ldap*" -task:"database" -flavor:"unstable" -category:"non-free"

where this line means that we search all packages that begins with ldap, that 
belong to database task, flavor unstable and category non-free. Obviously, 
all the three options (task, flavor, category) are optional.

This will be useful for search all packages in a concrete flavor (in a system 
with packages or several flavours) or when we want to search all non-free 
packages (that simply we do with "dpkg -l "*" -category:"non-free"").

This is one wish

Another is that dpkg allows to search what flavours are installed on my 
computer (if I only have unstable packages or unstable and testing), and idem 
to tasks and category.

I think that this two wishes are easy to implement and will be useful for 
users.

Thank you,
Xan.