Rectangular selection for Textadept

ta-rectselect.lua

local KEYSYMS = textadept.keys.KEYSYMS
keys.ar = {function()
    local t = _G.textadept
    t.statusbar_text = 'Rectangular selection'
    t.events.handle('update_ui')
    t.events.add_handler('keypress', function(code, shift, control, alt)
      if alt and KEYSYMS[code] == 'left' then
        buffer:char_left_rect_extend()
        return true
      elseif alt and KEYSYMS[code] == 'up' then
        buffer:line_up_rect_extend()
        return true
      elseif alt and KEYSYMS[code] == 'right' then
        buffer:char_right_rect_extend()
        return true
      elseif alt and KEYSYMS[code] == 'down' then
        buffer:line_down_rect_extend()
        return true
      else
        table.remove(textadept.events['keypresss'], 1)
        t.statusbar_text = ''
        t.events.handle('update_ui')
        return
       end
    end
, 1)
end
}