View difference between Paste ID: 1FBrE21V and nFSUKiYE

     ------------------------------------------------------------------
     --              Turtle Automatic Lava Collection                --
     --               By Scott Chamberlain (leftler)                 --
     -- Usage: place bucket in inventory and call with the           --
     --  arguments <blocks> [drop]                                   --
     --                                                              --
     -- The turtle travels 'blocks' forward and sucks all lava as    --
     -- fuel in then makes a U-turn and attempts to retreive lava on --
     -- the way back. The seccond parameter will tell the turtle to  --
     -- drop that many blocks after moving forward once.             --
     --                                                              --
     -- if the turtle is a mining turtle it will break any blocks    --
     -- blocking it's path                                           --
     ------------------------------------------------------------------
 
     local tArgs = { ... }
 
     if #tArgs == 0 then
       print("Usage: <blocks> [drop]")
       return
     end
 
     turtle.refuel()
 
     if turtle.getFuelLevel() == 0 then
       print("The turtle must have at least some fuel to start with.")
       return
     elseif turtle.getFuelLevel() == "unlimited" then
       print("This turtle does not use fuel to move")
       return
     end
 
     --Number of blocks to travel to get the lava
     local maxDistance = tArgs[1]
 
     --How deep to go to gather the lava
     local drop = 0
     if #tArgs >= 2 then
       drop = tonumber(tArgs[2])
     end
 
     --local counter for how far the turtle has travle
     local traveled = 0
 
     --A helper function to try and move forward, it will attempt to dig if it is blocked.
     local function moveForward()
       if turtle.forward() == false then
         --Failed to move, see if we can dig our way forward
         while turtle.dig() do
               --Keep digging till we can't dig any more, in case gravel is falling.
             end
             if turtle.forward() == false then
               print("I am either blocked or out of fuel.")
               return false
             end
       end
       return true
     end
 
     --A helper function to try and move down, it will attempt to dig if it is blocked.
     local function moveDown()
       if turtle.down() == false then
         --Failed to move, see if we can dig our way down
         turtle.digDown()
             if turtle.down() == false then
               print("I am either blocked or out of fuel.")
               return false
             end
       end
       return true
     end
 
     --A helper function to try and move down, it will attempt to dig if it is blocked.
     local function moveUp()
       if turtle.up() == false then
         --Failed to move, see if we can dig our way down
         while turtle.digUp() do
               --Keep digging till we can't dig any more, in case gravel is falling.
             end
             if turtle.up() == false then
               print("I am either blocked or out of fuel.")
               return false
             end
       end
       return true
     end
 
     dropDone = false
 
     --Attempt to travel to max distance for getting lava
     for i = 1, maxDistance do
       if moveForward() == false then
         print("Could not move forward the full requested distance, starting U-Turn early.")
             break
       end
       traveled = traveled + 1
 
       --drop to the requested depth
       if(dropDone == false) then
         for j = 1, drop do
               if moveDown() == false then
                 print("Could not drop the full distance")
                     drop = j - 1
                     end
             end
             dropDone = true
       end
 
       --grab the fule
       turtle.placeDown()
       if turtle.refuel() == false then
         --Whatever we picked up is invalid for fuel, put it back down
         turtle.placeDown()
       end
     end
 
     --Turn around move a block over and get more lava
     turtle.turnRight()
     moveForward()
     turtle.turnRight()
 
     --Travel back the same number of blocks we came
     for i = 1, traveled do
       turtle.placeDown()
       turtle.refuel()
 
       --Check to see if we need to go up yet
       if i == traveled then
         for j = 1, drop do
               moveUp()
             end
       end
 
       if moveForward() == false then
         --We are stuck, attempt to go up a level to get home
             if drop > 0 then
               repeat
                 moveUp()
                 drop = drop - 1
                     lastMove = moveForward()
               until lastMove == true or drop == 0
 
               if lastMove == false then
                 print("I am stuck!")
               end
             end
       end
     end
 
     turtle.turnRight()
     moveForward()
     turtle.turnRight()