Head over to Casa Natasha (or should that be Casha Natasa?) and read this. “In functional programming, instead of using the typical for-loops to solve problems, the use of head, tail, and recursion is favored to deal with elements in a list one at a time.”
I remember seeing something related in one of the Swift talks at WWDC but my brain is a little too blurred to remember which — I think it may have been value types. But now I really want to go back and re-watch that bit. (If you can think of which one it is, please drop a note, tweet, whatever. Thanks.)
In any case, cool stuff.