function Update(self)
   
   ...
   
   if self.FuturePos ~= nil then
      ConsoleMan:PrintString("Future was not null")
   end
   if self.LZpos ~= nil then
      ConsoleMan:PrintString("lz was not  null")
   end
   if self ~= nil then
      ConsoleMan:PrintString("self was not null")
   end
   local dist = SceneMan:ShortestDistance(self.FuturePos, self.LZpos, false).X
   if dist ~= nil then
      ConsoleMan:PrintString("dist was not null")
   end
   self:MoveLeftRight(self, dist, false)
   
   ...
end


function MoveLeftRight(self, dist, emergency)   
   
   if emergency then
      dist = dist*2
   end

   local change = self.XposPID:Update(dist, 0)

   if change > 2 then
      self.Controller.AnalogMove = Vector(change/30, 0)
   elseif change < -2 then
      self.Controller.AnalogMove = Vector(change/30, 0)
   end
end



----------------------------------------------------------------
Console Output
----------------------------------------------------------------
"Future was not null"
"Lz was not null"
"self was not null"
"dist was not null"
Error: Attemted to call MoveLeftRight(a nil value)

-- The controller class
   PIDController = {}
   PIDController.mt = {__index = PIDController}
   function PIDController:New(p_in, i_in, d_in, last_in, integral_in)
      return setmetatable(
         {
            p = p_in,
            i = i_in,
            d = d_in,
            last = last_in or 0,
            integral = integral_in or 0
         },
         PIDController.mt)
   end
   
   function PIDController:Update(input, target)
      local err = input - target
      local change = input - self.last
      self.last = input
      self.integral = self.integral + err
      return self.p*err + self.i*self.integral + self.d*change
   end

function MoveLeftRight(self, dist, emergency)   
    ...
end

function Create(self)
    function self:MoveLeftRight(dist, emergency)   
        ...
    end
end