Gregory's Server@neauoire It is entirely possible to create such abstractions in Uxntal or in Forth for that matter. In Scheme that has been the custom forever. So the criticism would then move to "but they aren't native" or something like that.
It's to my mind an idle debate, because what people are really saying is "I like what I know and I don't like change"
@wim_v12e I totally agree, it's like, it's all things that can be done, if a language made it harder or impossible to create these data structures then I can see a point here, but each time something is added to the core, then everyone has to carry this extra weight.