Select All Non-Null Layers.jsx

/**
 * @name Select All Non-Null Layers
 * @version 1.1
 * @author Kyle Martinez <www.kyle-martinez.com>
 *
 * @description Select all layers in a composition that are not a null layer.
 *
 * @license This script is provided "as is," without warranty of any kind, expressed or implied. In
 * no event shall the author be held liable for any damages arising in any way from the use of this
 * script.
 *
 * In other words, I'm just trying to help make life as an animator easier
 * "A rising tide lifts all boats." - John F. Kennedy, 1963
 */

(function() {
	try {
		app.beginUndoGroup("Select All Non-Null Layers");
		var comp = app.project.activeItem;
		var layers = comp.layers;
		var numLayers = layers.length;
		for (var l = 1; l <= numLayers; l++) {
			var layer = layers[l];
			if (layer.nullLayer !== true) {
				layer.selected = true;
			}
		}
	} catch (err) {
		alert(err);
	} finally {
		app.endUndoGroup();
	}
})();