Hello,

first, let me sketch my problem:

I need to manage an ordered inventory of things with a fixed number of slots (in the general sense of the word). Adding new things is mostly done by assigning them to a slot, but it would be nice to be able to just say "add this item" whereupon it will be stuffed into an arbitrary free slot. For removal the same rules are in effect. Slots can be empty, accessing them should return NIL.

I have found the MAP type to be most appropriate for this, but I'm running into problems. For example, there's no SETF expander for WITH2, thus rendering ADJOINF non-functional for MAPs. Also, I haven't found any way to find/remove elements in the image of the map, all operations seem to work on the domain only.

Can you help me? Should I subclass MAP or another collection type?

Leslie