keychord.lua

   1 -- Keyboard driver
   2
   3 Modifiers = {'lctrl', 'rctrl', 'lalt', 'ralt', 'lshift', 'rshift', 'lgui', 'rgui'}
   4
   5 function App.keypressed(key, scancode, isrepeat)
   6   if array.find(Modifiers, key) then
   7     -- do nothing when the modifier is pressed
   8     return
   9   end
  10   -- include the modifier(s) when the non-modifer is pressed
  11   App.keychord_press(App.combine_modifiers(key), key)
  12 end
  13
  14 function App.combine_modifiers(key)
  15   local result = ''
  16   if App.ctrl_down() then
  17     result = result..'C-'
  18   end
  19   if App.alt_down() then
  20     result = result..'M-'
  21   end
  22   if App.shift_down() then
  23     result = result..'S-'  -- don't try to use this with letters/digits
  24   end
  25   if App.cmd_down() then
  26     result = result..'s-'
  27   end
  28   result = result..key
  29   return result
  30 end
  31
  32 function App.any_modifier_down()
  33   return App.ctrl_down() or App.alt_down() or App.shift_down() or App.cmd_down()
  34 end
  35
  36 function App.ctrl_down()
  37   return App.modifier_down('lctrl') or App.modifier_down('rctrl')
  38 end
  39
  40 function App.alt_down()
  41   return App.modifier_down('lalt') or App.modifier_down('ralt')
  42 end
  43
  44 function App.shift_down()
  45   return App.modifier_down('lshift') or App.modifier_down('rshift')
  46 end
  47
  48 function App.cmd_down()
  49   return App.modifier_down('lgui') or App.modifier_down('rgui')
  50 end
  51
  52 function App.is_cursor_movement(key)
  53   return array.find({'left', 'right', 'up', 'down', 'home', 'end', 'pageup', 'pagedown'}, key)
  54 end
  55
  56 array = {}
  57
  58 function array.find(arr, elem)
  59   if type(elem) == 'function' then
  60     for i,x in ipairs(arr) do
  61       if elem(x) then
  62         return i
  63       end
  64     end
  65   else
  66     for i,x in ipairs(arr) do
  67       if x == elem then
  68         return i
  69       end
  70     end
  71   end
  72   return nil
  73 end
  74
  75 function array.any(arr, f)
  76   for i,x in ipairs(arr) do
  77     local result = f(x)
  78     if result then
  79       return result
  80     end
  81   end
  82   return false
  83 end