Bios:339: [String "branch"]:141: '<Name>' Expected

--According to Benjamin Buford "Bubba" Blue I should make notes.
-- aLenght is the Actual length of the branch mine. length is the desired length of the branch mine in blocks. The height is the desired height of the branch mine in 2 meter high floors. progress indicates the stage of the mining process; 1 is branch; 2 is trunk; 3 is level change.
local arg1,arg2 = ...
local length = tonumber(arg1)
local zLength = length
local height = tonumber(arg2)
local aLength = 0
local aHeight = 1
local progress = 0
--Checks if the arguments are valid.
if length == nil or height == nil then
print[[ Please only use numbers.
Usage: oBranch <length> <height>]]
return false
elseif length < 3 or height < 2 then
print[[ Please only use positive numbers.
This message might also have occurred because the entered numbers were too low.
Usage: oBranch <height> <height>]]
return false
end
--Changes valid length to match the second floors' (2nd, 4th, 6th, etc.) branches.
local function lengthChange()
if length % 4 == 3 then
  zLength = length
  print( "The branch mine will be the desired ", length, "." )
elseif length % 4 == 2 then
  zLength = length - 3
  print( "I'm sorry, we have had to change the length from ", length, " to ", zLength, ". I'm sorry for the inconvenience." )
elseif length % 4 == 1 then
  zLength = length - 2
  print( "I'm sorry, we have had to change the length from ", length, " to ", zLength, ". I'm sorry for the inconvenience." )
else
  zLength = length - 1
  print( "I'm sorry, we have had to change the length from ", length, " to ", zLength, ". I'm sorry for the inconvenience." )
end
end
lengthChange()

--[[Source for function refuel(): tunnel, a standard CC mining turtle program. All credit goes to the original author.
It refuels :o/>]]
local function refuel()
local fuelLevel = turtle.getFuelLevel()
if fuelLevel == "unlimited" or fuelLevel > 0 then
  return
end
local function tryRefuel()
  for n=1,16 do
   if turtle.getItemCount(n) > 0 then
    turtle.select(n)
    if turtle.refuel(1) then
	 turtle.select(1)
	 return true
    end
   end
  end
  turtle.select(1)
  return false
end

if not tryRefuel() then
  print( "Add more fuel to continue." )
  while not tryRefuel() do
   sleep(1)
  end
  print( "Resuming Tunnel." )
end
end
--Digs forward.
local function frontDig()
while turtle.detect() do
  turtle.dig()
  sleep(0.25)
end
end
--Digs up.
local function upDig()
while turtle.detectUp() do
  turtle.digUp()
  sleep(0.25)
end
end
--Digs down.
local function downDig()
while turtle.detectDown() do
  turtle.digDown()
  sleep(0.25)
end
end
--Goes forward.
local function frontGo()
refuel()
frontDig()
while turtle.attackUp() do
  turtle.attackUp()
  sleep(0.25)
end
turtle.forward()
end
--Goes up.
local function upGo()
refuel()
upDig()
while turtle.attackUp() do
  turtle.attackUp()
  sleep(0.25)
end
turtle.up()
end
--Goes down.
local function downGo()
refuel()
downDig()
while turtle.attackDown() do
  turtle.attackDown()
  sleep(0.25)
end
turtle.down()
end
--Turns 'round.
local function roundTurn()
for 1,6 do
  turtle.turnLeft()
end
end
--Makes branchMine()
local function branchMine()
--Makes branches.
local function branch()
  local function stick()
   for 1,6 do
    frontGo()
    upDig()
   end
  end
  turtle.turnLeft()
  stick()
  roundTurn()
  stick()
  stick()
  roundTurn()
  stick()
  turtle.turnRight()
end
--Makes the main trunk
local function trunk()
  frontGo()
  turtle.turnLeft()
  frontDig()
  upGo()
  frontDig()
  roundTurn()
  frontDig()
  downGo()
  frontDig()
  turtle.turnRight()
  if aLength ~= zLength then
   frontGo()
  end
end
--Elevates to the next floor
local function level()
  upGo()
  upGo()
  roundTurn()
end
--Decides the order of mining.
if progress == 1 then
  branch()
  aLength = aLength + 1
  progress = progress + 1
elseif progress == 2 or progress == 3 or progress == 4 then
  trunk()
  aLength = aLength + 1
  progress = progress + 1
elseif progress == 0 then
  level()
  aHeight = height + 1
  progress = 1
end
--Makes the circle round
if progress == 5 then
  progress = 1
end

if aLength % 25 then
  print( "The branch mine is now ", aLength, " blocks long." )
end

if aLength == zLength then
  print( "Finished floor number ", aHeight, "." )
  if aHeight == 1 then
   print( "The branch mine is now the appointed/desired ", aLength, " blocks long." )
  end
  if aHeight ~= height  then
   progress = 0
   aLength = 0
  end
end
end
print( "Mining ", zLength, " blocks long branch mine." )
--Makes branch mine until desired length is achieved.
while aLength < zLength do
branchMine()
end