code: func (js *joystickState) getButton(joystick Joystick, button int) bool {
  	// Check that the joystick and button is valid, return false by default
  	if js.buttons[joystick] == nil || button >= len(js.buttons[joystick]) || button < 0 {
  		return false
  	}
  	return js.buttons[joystick][byte(button)] == 1
  }
docs: // Returns if a button on a joystick is down, returning false if the button or joystick is invalid.