They are not very old either, at least not compared to Lisp (60s), scheme and the MLs (70s/80s). Haskell is quite brand spanking new in comparison to the old guard.
What C# lacks for me in FP, case matching, has little to do with purity. The FP story involves purity but is not dominated by it. List comprehensions still work in C# even though you can theoretically side effect in your select and filter functions.
What C# lacks for me in FP, case matching, has little to do with purity. The FP story involves purity but is not dominated by it. List comprehensions still work in C# even though you can theoretically side effect in your select and filter functions.