Hi! I'm looking for a plugin that can do the following (minimum requirement):

Given one playlist X and an "everything" playlist A, create a new playlist Y that contains the songs which are in A but not in X (in set language, Y is the complement of X with regard to A).

Does anyone know if such a plugin is available?

Ideally the plugin would also be able to accept for the reference "everything" playlist A either an existing playlist or a root directory (like the database thingy has a root directory and ignores files that are in other directory trees).

If there's interest for making such a plugin, then alternatively one could think of the goal of the plugin to be a playlist-combining plugin which should be able to do the commands "NOT" (minimum) and possibly also "OR" (which can be done simply by copying playlist J into playlist K and reducing with the "remove duplicates"), "AND", and possibly even "XOR", "NAND", etc, but the crucial one is "NOT". If someone were really adventurous, this plugin could be extended to allow bracketing, to give something like: make a new playlist of all songs from playlists X and Y that are not in playlist A, B, C, D, nor E.

The more general plugin might also offer the option to save all playlists, as this feature has been requested a couple of times now in these fora.

Any ideas/suggestions? Maybe this plugin, or at least the "NOT" plugin already exists?

Many thanks!