LearnBoost antiscroll modified to compile under closure's advanced mode. Remember to pass it a jQuery externs file.

gistfile1.txt

// ==ClosureCompiler==
// @compilation_level ADVANCED_OPTIMIZATIONS
// @output_file_name default.js
// ==/ClosureCompiler==
// ADD YOUR CODE HERE

(function ($) {
  /**
	 * Augment jQuery prototype.
	 */

	$.fn['antiscroll'] = function (options) {
		return this.each(function () {
			if ($(this).data('$.A')) {
				$(this).data('$.A').destroy();
			}

			$(this).data('$.A', new $.Antiscroll(this, options));
		});
	};

	/**
	 * Expose constructor.
	 */

	$.Antiscroll = Antiscroll;

	/**
	 * Antiscroll pane constructor.
	 *
	 * @constructor
	 * @param {Element|jQuery} el
	 * @param {Object} opts
	 */

	function Antiscroll(el, opts) {
		this.el = $(el);
		this.options = opts || {};

		this.x = (false !== this.options['x']) || this.options['forceHorizontal'];
		this.y = (false !== this.options['y']) || this.options['forceVertical'];
		this.autoHide = false !== this.options['autoHide'];
		this.padding = undefined == this.options['padding'] ? 2 : this.options['padding'];

		/** @type {jQuery} */
		this.inner = this.el.find('.antiscroll-inner');
		this.inner.css({
			'width': '+=' + (this.y ? scrollbarSize() : 0),
			'height': '+=' + (this.x ? scrollbarSize() : 0)
		});

		var cssMap = {};
		if (this.x) cssMap.width = '+=' + scrollbarSize();
		if (this.y) cssMap.height = '+=' + scrollbarSize();
		this.inner.css(cssMap);

		this.refresh();
	};

	/**
	 * refresh scrollbars
	 *
	 */

	Antiscroll.prototype.refresh = function () {
		var needHScroll = this.inner.get(0).scrollWidth > this.el.width() + (this.y ? scrollbarSize() : 0),
			needVScroll = this.inner.get(0).scrollHeight > this.el.height() + (this.x ? scrollbarSize() : 0);

		if (this.x) {
			if (!this.horizontal && needHScroll) {
				this.horizontal = new Scrollbar.Horizontal(this);
			}
			else if (this.horizontal && !needHScroll) {
				this.horizontal.destroy();
				this.horizontal = null;
			}
			else if (this.horizontal) {
				this.horizontal.update();
			}
		}

		if (this.y) {
			if (!this.vertical && needVScroll) {
				this.vertical = new Scrollbar.Vertical(this);
			}
			else if (this.vertical && !needVScroll) {
				this.vertical.destroy();
				this.vertical = null;
			}
			else if (this.vertical) {
				this.vertical.update();
			}
		}
	};

	/**
	 * Cleans up.
	 *
	 * @return {Antiscroll} for chaining
	 */

	Antiscroll.prototype.destroy = function () {
		if (this.horizontal) {
			this.horizontal.destroy();
			this.horizontal = null
		}
		if (this.vertical) {
			this.vertical.destroy();
			this.vertical = null
		}
		return this;
	};

	/**
	 * Rebuild Antiscroll.
	 *
	 * @return {Antiscroll} for chaining
	 */

	Antiscroll.prototype.rebuild = function () {
		this.destroy();
		this.inner.attr('style', '');
		Antiscroll.call(this, this.el, this.options);
		return this;
	};

	/**
	 * Scrollbar constructor.
	 *
	 * @constructor
	 * @this {Scrollbar.Horizontal|Scrollbar.Vertical}
	 * @param {Antiscroll} pane
	 */

	function Scrollbar(pane) {
		this.pane = pane;
		this.pane.el.append(this.el);
		this.innerEl = this.pane.inner.get(0);

		this.dragging = false;
		this.enter = false;
		this.shown = false;

		// hovering
		// mouseenter = z
		this.pane.el.mouseenter($.proxy(this, 'z'));
		// mouseleave = y
		this.pane.el.mouseleave($.proxy(this, 'y'));

		// dragging
		// mousedown = x
		this.el.mousedown($.proxy(this, 'x'));

		// scrolling
		// scroll = u
		this.innerPaneScrollListener = $.proxy(this, 'u');
		this.pane.inner.scroll(this.innerPaneScrollListener);

		// wheel -optional-
		// mousewheel = w
		this.innerPaneMouseWheelListener = $.proxy(this, 'w');
		this.pane.inner.bind('mousewheel', this.innerPaneMouseWheelListener);

		// show
		var initialDisplay = this.pane.options['initialDisplay'];

		if (initialDisplay !== false) {
			this.show();
			if (this.pane.autoHide) {
				this.hiding = setTimeout($.proxy(this, 'hide'), parseInt(initialDisplay, 10) || 3000);
			}
		}
	};

	/**
	 * Cleans up.
	 *
	 * @return {Scrollbar} for chaining
	 */

	Scrollbar.prototype.destroy = function () {
		this.el.remove();
		this.pane.inner.unbind('scroll', this.innerPaneScrollListener);
		this.pane.inner.unbind('mousewheel', this.innerPaneMouseWheelListener);
		return this;
	};

	/**
	 * Called upon mouseenter.
	 *
	 */

	Scrollbar.prototype['z'] = function () {
		this.enter = true;
		this.show();
	};

	/**
	 * Called upon mouseleave.
	 *
	 */

	Scrollbar.prototype['y'] = function () {
		this.enter = false;

		if (!this.dragging) {
			if (this.pane.autoHide) {
				this.hide();
			}
		}
	};

	/**
	 * Called upon wrap scroll.
	 *
	 */

	Scrollbar.prototype['u'] = function () {
		if (!this.shown) {
			this.show();
			if (!this.enter && !this.dragging) {
				if (this.pane.autoHide) {
					this.hiding = setTimeout($.proxy(this, 'hide'), 1500);
				}
			}
		}

		this.update();
	};

	/**
	 * Called upon scrollbar mousedown.
	 *
	 */

	Scrollbar.prototype['x'] = function (ev) {
		ev.preventDefault();

		this.dragging = true;

		this.startPageY = ev.pageY - parseInt(this.el.css('top'), 10);
		this.startPageX = ev.pageX - parseInt(this.el.css('left'), 10);

		// prevent crazy selections on IE
		this.el[0].ownerDocument.onselectstart = function () {
			return false;
		};

		// mousemove = v
		var pane = this.pane,
			move = $.proxy(this, 'v'),
			self = this

			$(this.el[0].ownerDocument)
				.mousemove(move)
				.mouseup(function () {
				self.dragging = false;
				this.onselectstart = null;

				$(this).unbind('mousemove', move);

				if (!self.enter) {
					self.hide();
				}
			});
	};

	/**
	 * Show scrollbar.
	 * @param {number=} duration
	 *
	 */

	Scrollbar.prototype.show = function (duration) {
		if (!this.shown && this.update()) {
			this.el.addClass('antiscroll-scrollbar-shown');
			if (this.hiding) {
				clearTimeout(this.hiding);
				this.hiding = null;
			}
			this.shown = true;
		}
	};

	/**
	 * Hide scrollbar.
	 *
	 */

	Scrollbar.prototype.hide = function () {
		if (this.pane.autoHide !== false && this.shown) {
			// check for dragging
			this.el.removeClass('antiscroll-scrollbar-shown');
			this.shown = false;
		}
	};

	/**
	 * Horizontal scrollbar constructor
	 *
	 * @constructor
	 * @extends Scrollbar
	 */

	Scrollbar.Horizontal = function (pane) {
		this.el = $('<div class="antiscroll-scrollbar antiscroll-scrollbar-horizontal">');
		Scrollbar.call(this, pane);
	};

	/**
	 * Inherits from Scrollbar.
	 */

	inherits(Scrollbar.Horizontal, Scrollbar);

	/**
	 * Updates size/position of scrollbar.
	 *
	 */

	Scrollbar.Horizontal.prototype.update = function () {
		var paneWidth = this.pane.el.width(),
			trackWidth = paneWidth - this.pane.padding * 2,
			innerEl = this.pane.inner.get(0)

			this.el
				.css('width', trackWidth * paneWidth / innerEl.scrollWidth)
				.css('left', trackWidth * innerEl.scrollLeft / innerEl.scrollWidth);

		return paneWidth < innerEl.scrollWidth;
	};

	/**
	 * Called upon drag.
	 *
	 */

	Scrollbar.Horizontal.prototype['v'] = function (ev) {
		var trackWidth = this.pane.el.width() - this.pane.padding * 2,
			pos = ev.pageX - this.startPageX,
			barWidth = this.el.width(),
			innerEl = this.pane.inner.get(0)

			// minimum top is 0, maximum is the track height
			var y = Math.min(Math.max(pos, 0), trackWidth - barWidth);

		innerEl.scrollLeft = (innerEl.scrollWidth - this.pane.el.width()) * y / (trackWidth - barWidth);
	};

	/**
	 * Called upon container mousewheel.
	 *
	 */

	Scrollbar.Horizontal.prototype['w'] = function (ev, delta, x, y) {
		if ((x < 0 && 0 == this.pane.inner.get(0).scrollLeft) ||
			(x > 0 && (this.innerEl.scrollLeft + Math.ceil(this.pane.el.width()) == this.innerEl.scrollWidth))) {
			ev.preventDefault();
			return false;
		}
	};

	/**
	 * Vertical scrollbar constructor
	 *
	 * @constructor
	 * @extends Scrollbar
	 */

	Scrollbar.Vertical = function (pane) {
		this.el = $('<div class="antiscroll-scrollbar antiscroll-scrollbar-vertical">');
		Scrollbar.call(this, pane);
	};

	/**
	 * Inherits from Scrollbar.
	 */

	inherits(Scrollbar.Vertical, Scrollbar);

	/**
	 * Updates size/position of scrollbar.
	 *
	 */

	Scrollbar.Vertical.prototype.update = function () {
		var paneHeight = this.pane.el.height(),
			trackHeight = paneHeight - this.pane.padding * 2,
			innerEl = this.innerEl;

		var scrollbarHeight = trackHeight * paneHeight / innerEl.scrollHeight;
		scrollbarHeight = scrollbarHeight < 20 ? 20 : scrollbarHeight;

		var topPos = trackHeight * innerEl.scrollTop / innerEl.scrollHeight;

		if ((topPos + scrollbarHeight) > trackHeight) {
			var diff = (topPos + scrollbarHeight) - trackHeight;
			topPos = topPos - diff - 3;
		}

		this.el
			.css('height', scrollbarHeight)
			.css('top', topPos);

		return paneHeight < innerEl.scrollHeight;
	};

	/**
	 * Called upon drag.
	 */

	Scrollbar.Vertical.prototype['v'] = function (ev) {
		var paneHeight = this.pane.el.height(),
			trackHeight = paneHeight - this.pane.padding * 2,
			pos = ev.pageY - this.startPageY,
			barHeight = this.el.height(),
			innerEl = this.innerEl

			// minimum top is 0, maximum is the track height
		var y = Math.min(Math.max(pos, 0), trackHeight - barHeight);

		innerEl.scrollTop = (innerEl.scrollHeight - paneHeight) * y / (trackHeight - barHeight);
	};

	/**
	 * Called upon container mousewheel.
	 *
	 */

	Scrollbar.Vertical.prototype['w'] = function (ev, delta, x, y) {
		if ((y > 0 && 0 == this.innerEl.scrollTop) ||
			(y < 0 && (this.innerEl.scrollTop + Math.ceil(this.pane.el.height()) == this.innerEl.scrollHeight))) {
			ev.preventDefault();
			return false;
		}
	};

	/**
	 * Cross-browser inheritance.
	 *
	 * @param {Function} ctorA
	 * @param {Function} ctorB
	 */

	function inherits(ctorA, ctorB) {
		/** @constructor */
		function f() {};
		f.prototype = ctorB.prototype;
		ctorA.prototype = new f;
	};


	var size;

	/**
	 * Scrollbar size detection.
	 * @return {number}
	 */

	function scrollbarSize() {
		if (size === undefined) {
			var div = $(
				'<div class="antiscroll-inner" style="width:50px;height:50px;overflow-y:scroll;' + 'position:absolute;top:-200px;left:-200px;"><div style="height:100px;width:100%">' + '</div>');

			$('body').append(div);
			var w1 = $(div).innerWidth();
			var w2 = $('div', div).innerWidth();
			$(div).remove();

			size = w1 - w2;
		}

		return size;
	};
	
})(jQuery);