Trying to get quartering to work in Hammerspoon

window_gridding.lua

local function originalarrows()
  prefix:bind('', 'Left', function() leftwin(false) end)
  prefix:bind('', 'Right', function() rightwin(false) end)
  prefix:bind('', 'Up', function() topwin(false) end)
  prefix:bind('', 'Down', function() botwin(false) end)
end

local function newarrows()
  prefix:bind('', 'Left', function() leftwin(true) end)
  prefix:bind('', 'Right', function() rightwin(true) end)
  prefix:bind('', 'Up', function() topwin(true) end)
  prefix:bind('', 'Down', function() botwin(true) end)
end

local function leftwin(i)
  local win = hs.window.focusedWindow()
  local f = win:frame()
  local screen = win:screen()
  local max = screen:frame()

  if i then
    f.x = f.x
    f.y = f.y
    f.w = max.w / 2
    f.h = f.y
    win:setFrame(f)
    originalarrows()
    prefix:exit()
  else
    f.x = max.x
    f.y = max.y
    f.w = max.w / 2
    f.h = max.h
    newarrows()
    win:setFrame(f)
  end
end

local function rightwin(i)
  local win = hs.window.focusedWindow()
  local f = win:frame()
  local screen = win:screen()
  local max = screen:frame()

  if i then
    f.x = f.x
    f.y = f.y
    f.w = max.w / 2
    f.h = f.y
    win:setFrame(f)
    originalarrows()
    prefix:exit()
  else
    f.x = max.x + (max.w / 2)
    f.y = max.y
    f.w = max.w / 2
    f.h = max.h
    newarrows()
    win:setFrame(f)
  end
end

local function topwin(i)
  local win = hs.window.focusedWindow()
  local f = win:frame()
  local screen = win:screen()
  local max = screen:frame()

  if i then
    f.x = f.x
    f.y = f.y
    f.w = f.w
    f.h = max.h / 2
    win:setFrame(f)
    originalarrows()
    prefix:exit()
  else
    f.x = max.x
    f.y = max.y
    f.w = max.w
    f.h = max.h / 2
    newarrows()
    win:setFrame(f)
  end
end

local function botwin(i)
  local win = hs.window.focusedWindow()
  local f = win:frame()
  local screen = win:screen()
  local max = screen:frame()

  if i then
    f.x = f.x
    f.y = f.y
    f.w = f.w
    f.h = max.h / 2
    win:setFrame(f)
    originalarrows()
    prefix:exit()
  else
    f.x = max.x
    f.y = max.y + (max.h / 2)
    f.w = max.w
    f.h = max.h / 2
    newarrows()
    win:setFrame(f)
  end
end

originalarrows()

line 2: attempt to call a nil value (global 'leftwin')
line 3: attempt to call a nil value (global 'rightwin')
line 4: attempt to call a nil value (global 'topwin')
line 5: attempt to call a nil value (global 'botwin')