Sheer awesomeness! I've been waiting for along time for a decent collections lib for D2. I haven't tested it extensively, but it definitely builds w/o a hitch (using a custom build script I wrote that builds dcollections and other libs I use in one go) and works for the toy examples I tested.
One small comment, though: Looking at your ArrayList code, wouldn't it make more sense to use a capacity field here than to use the builtin array appending mechanism, given that this is a class, not a struct?
