I consider myself experienced programmer in the sense that I have been working with various different languages and abstractions all the way from asm to object-oriented C++ and object-functionalish Python code.
I'm currently looking for a book about Ruby. The ideal book would assume that the reader already knows how to program some language and just tells you what makes this language special and how to effectively use it. Stack has several questions about Ruby books but none of them seem to fit this niche. I'd appreciate if you could suggest some books fitting my criteria.