Chord keys in Hammerspoon

hammerspoon_cord_keys.lua

-- Can Hammerspoon create chord / prefix keys like Emacs?
local ctrlXActive = false
local hotkeyModal = hs.hotkey.modal.new()

function startCtrlX()
  ctrlXActive = true

  hs.timer.doAfter(1, clearCtrlX)
end

function clearCtrlX()
  print('Clearing ctrlXActive flag.')
  ctrlXActive = false
end

function forwardOrOpen()
  hotkeyModal:exit()
  
  if ctrlXActive then
    print('Opening file.')
    hs.eventtap.keyStroke('cmd', 'o')
  else
    print('Moving cursor forward.')
    hs.eventtap.keyStroke(nil, 'right')
  end

  hotkeyModal:enter()

  clearCtrlX()
end

hotkeyModal:bind({'ctrl'}, 'x', startCtrlX, nil, nil)
hotkeyModal:bind({'ctrl'}, 'f', forwardOrOpen, nil, nil)
hotkeyModal:enter()