Solution for http://www.kurilo.su/programmers/

turtle

if (direction == '') {
 direction = 'east';
}
var dirs; 
var look = function (dir) {
  if (dir == 'north') return north; 
  else if (dir == 'south') return south; 
  else if (dir == 'east') return east; 
  else if (dir == 'west') return west; 
}

if (direction == 'north') 
   dirs = ['east', 'north', 'west', 'south'];
else if (direction == 'west') 
   dirs = ['north', 'west', 'south', 'east'];
else if (direction == 'south') 
   dirs = ['west', 'south', 'east', 'north'];
else if (direction == 'east') 
   dirs = ['south', 'east', 'north', 'west'];

for (var i=0; i<=3; i++) {
  var dir = dirs[i];
  var dir_look = look(dir)
  if (dir_look == 3 || dir_look == 0) {
    console.log('returning ' + dir);

    result = dir;
    break;
  }
}