Well recursion would call subs from subs, and recursion can do in a very small amount of code what would take many lines to accomplish.  However since gosubs are more cpu intensive than other activities, recursion ( I believe ) would become very slow in easyuo very fast.  Never actually run tests with it in easy uo, just remembering little programs I played with back in the day.

While #True
{
 For %i 1 %endspot
 {
  set %x %x . %i     ;this is for use with CEOs rail writter
  set %y %y . %i
  set %z %z . %i
  set %timeout #systime + 15000   ;if you can't get to the waypoint in 15 seconds, skip the rail point
  While ! ( #charposx = %x && #charposy = %y ) && %timeout > #systime
  {
   event pathfind %x %y %z
   wait 1
   if ABS ( #charposx - %x ) > 16 || ABS ( #charposy - %y ) > 16
   {
    set %i %i + 1
    set %x %x . %i
    set %y %y . %i
    set %z %z . %i
   };if it looks like the rail point is too far away, skip to the next rail point
   gosub dosomethingsub
  };while
 };for
};while

sub dosomethingsub
while %dosomething = #True
{
 event pathfind #charposx #charposy #charposz
 gosub slayyourenemiessub
}
return

Well this is how I would do it.  I haven't tested this code, its just a modified snippet from a script I wrote.

I normally use this website for monster IDs http://euo.oseaco.com/misc/Scripts/