Out of the loop

If you made it through that lengthy post and are still interested, let me add that many concepts from functional programming languages have made it into other languages over the years. Personally, I'm most familiar with C# which has functions that take other functions as parameters, lambda functions (functions without a name that you can just define directly where you use them as a parameter), simple list operations that take functions (filtering, sorting, transforming...) and to some extent pattern matching. From what I've heard, newer versions of Java have much of that as well and some of those features have even made it into C++ (from C++11 onwards) though in that case the syntax is a bit hard to read.