Button_handlers = {}

  State.button_handlers = {}

        button('draw', {x=4,y=y+4, w=12,h=12, color={1,1,0},

        button(State, 'draw', {x=4,y=y+4, w=12,h=12, color={1,1,0},

  if propagate_to_button_handlers(x,y, mouse_button) then

  if propagate_to_button_handlers(State, x,y, mouse_button) then

Button_handlers = {}

function button(name, params)

function button(State, name, params)
  if State.button_handlers == nil then
    State.button_handlers = {}
  end

  table.insert(Button_handlers, params)

  table.insert(State.button_handlers, params)

function propagate_to_button_handlers(x, y, mouse_button)
  for _,ev in ipairs(Button_handlers) do

function propagate_to_button_handlers(State, x, y, mouse_button)
  if State.button_handlers == nil then
    return
  end
  for _,ev in ipairs(State.button_handlers) do