if (typeof(gll) == "undefined") {
  gll = { };
}

gll.show = function(id, isBlock) {
  document.getElementById(id).style.display = isBlock ? "block" : "inline";
}

gll.hide = function(id) {
  document.getElementById(id).style.display = "none";
}

gll.makeVisible = function(id) {
  document.getElementById(id).style.visibility = "visible";
}

gll.makeInvisible = function(id) {
  document.getElementById(id).style.visibility = "hidden";
}

gll.toggle = function(id, isBlock) {
  var element = document.getElementById(id);
  if (element.style.display == "none") {
	document.getElementById(id).style.display = isBlock ? "block" : "inline";
	return true;
  } else {
	document.getElementById(id).style.display = "none";
	return false;
  }
}

gll.hidelist = function(ids) {
  for (var i = 0; i < ids.length; i++) {
	gll.hide(ids[i]);
  }
}

gll.showlist = function(ids, isBlock) {
  for (var i = 0; i < ids.length; i++) {
	gll.show(ids[i], isBlock);
  }
}