Learning the ML programming language is a lot of fun. This is my first in-depth initiation into the exciting world of functional programming. Here's something to whet your appetite, an elegant function for appending two lists of any type:

fun append e =
    case e of
        ([],ys) => ys
      | (x::xs,ys) => x :: append(xs,ys)

Here we are passing the function append an expression e, and if the pattern matches empty string plus string we stop, otherwise we prepend the first element to the tail appended to the list.

I am following the online Coursera training by the University of Washington called Programming Languages given by Dan Grossman.

Great stuff to keep my aging brain cells oiled and running efficiently.