Aptitude – How to Show Only Installed Packages by Executing ‘aptitude search’

This behavior is controlled by the option Apt::AutoRemove::SuggestsImportant.

Option: Apt::AutoRemove::SuggestsImportant

Default: true

Description: If this option is true, then aptitude will not consider packages to be unused (and thus will not automatically remove them) as long as any installed package suggests them. For more information, see the section called “Managing automatically installed packages”.

http://aptitude.alioth.debian.org/doc/en/ch02s05s05.html#configApt-AutoRemove-SuggestsImportant

You can set this option to false in one of aptitude's configuration files, to let aptitude automatically remove packages that are only suggested by other packages. E.g., edit or create /etc/apt/apt.conf and add the following line

Apt::AutoRemove::SuggestsImportant false;

The argument of ?depends, like any other directive, is a search pattern. The pattern "vim" is a regular expression that the package name must contain. To search for an exact package name, you need to anchor the regex: "^vim$".

aptitude search '?depends("^vim$")'
aptitude search '?depends(^vim$)'
aptitude search '~D^vim$'

You can also use the ?exact-name directive, but for some reason, at least with aptitude 0.6.6, it's slower.

aptitude search '?depends(?exact-name(vim))'