Ability to move window to east and west screens if we are already east or west wall.

init.lua

function movewindow_righthalf()
  local win = window.focusedwindow()
  local win_size = win:size()
  local win_point = win:topleft()
  local newframe = win:screen():frame_without_dock_or_menu()

  newframe.w = newframe.w / 2
  newframe.x = newframe.x + newframe.w -- comment out this line to push it to left half of screen

  local frame_already_on_east_wall = newframe.h == win_size.h and newframe.w == win_size.w and
    newframe.x == win_point.x and newframe.y == win_point.y

  if frame_already_on_east_wall then
    local screen = win:screen():toeast()

    if screen then
      local frame_to_east = screen:frame_without_dock_or_menu()

      frame_to_east.w = frame_to_east.w / 2

      win:setframe(frame_to_east)
    end
  else
    win:setframe(newframe)
  end
end

function movewindow_lefthalf()
  local win = window.focusedwindow()
  local win_size = win:size()
  local win_point = win:topleft()
  local newframe = win:screen():frame_without_dock_or_menu()

  newframe.w = newframe.w / 2

  local frame_already_on_west_wall = newframe.h == win_size.h and newframe.w == win_size.w and
    newframe.x == win_point.x and newframe.y == win_point.y

  if frame_already_on_west_wall then
    local screen = win:screen():towest()

    if screen then
      local frame_to_west = screen:frame_without_dock_or_menu()

      frame_to_west.w = frame_to_west.w / 2
      frame_to_west.x = frame_to_west.x + frame_to_west.w

      win:setframe(frame_to_west)
    end
  else
    win:setframe(newframe)
  end
end