-function tail(n, f, s, var)
+-- Skip the first n items an iterator returns
+function it.skip(n, f, s, var)
+ for i=1,n do
+ var = f(s, var);
+ end
+ return f, s, var;
+end
+
+-- Return the last n items an iterator returns
+function it.tail(n, f, s, var)