How to move an application between monitors in Hammerspoon?

At work I have a 3 monitor setup. I would like to move the current application to a second or a third monitor with a key binding. How to do that?

The screen library helps finding the right "display". allScreens lists the displays in the same order as they are defined by the system. The hs.window:moveToScreen function moves to a given screen, where it's possible to set the UUID.

The following code works for me. Hitting CTRL+ALT+CMD+ 3 moves the currently focused window to display 3, same as if you would choose "Display 3" in the Dock's Option menu.

function moveWindowToDisplay(d)
  return function()
    local displays = hs.screen.allScreens()
    local win = hs.window.focusedWindow()
    win:moveToScreen(displays[d], false, true)
  end
end

hs.hotkey.bind({"ctrl", "alt", "cmd"}, "1", moveWindowToDisplay(1))
hs.hotkey.bind({"ctrl", "alt", "cmd"}, "2", moveWindowToDisplay(2))
hs.hotkey.bind({"ctrl", "alt", "cmd"}, "3", moveWindowToDisplay(3))