From 98302beddde613a77f63f8ab313227c33369041a Mon Sep 17 00:00:00 2001
From: euzuro <euzuro@metacarta.com>
Date: Mon, 3 Jul 2006 14:11:48 +0000
Subject: [PATCH] same-case these functions for if there is no baselayer. in
 theory, these should never be called if no baselayer is set... but one never
 knows what a user will do. So instead of crashing, we will just return null.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@857 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
---
 lib/OpenLayers/Map.js | 32 ++++++++++++++++++++++++++------
 1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/lib/OpenLayers/Map.js b/lib/OpenLayers/Map.js
index 086f674f30..fa2441d9d7 100644
--- a/lib/OpenLayers/Map.js
+++ b/lib/OpenLayers/Map.js
@@ -641,27 +641,47 @@ OpenLayers.Map.prototype = {
 
     /**
      * @returns A Bounds object which represents the lon/lat bounds of the 
-     *          current viewPort.
+     *          current viewPort. 
+     *          If no baselayer is set, returns null.
      * @type OpenLayers.Bounds
      */
     getExtent: function () {
-        return this.baseLayer.getExtent();
+        var extent = null;
+        
+        if (this.baseLayer != null) {
+            extent = this.baseLayer.getExtent();
+        }
+        return extent;
     },
 
     /**
-    * @type float
-    */
+     * @returns The current resolution of the map. 
+     *          If no baselayer is set, returns null.
+     * @type float
+     */
     getResolution: function () {
-        return this.baseLayer.getResolution();
+        var resolution = null;
+        
+        if (this.baseLayer != null) {
+            resolution = this.baseLayer.getResolution();
+        }
+        return resolution;
     },
 
     /**
     * @param {OpenLayers.Bounds} bounds
     *
+    * @returns A suitable zoom level for the specified bounds.
+    *          If no baselayer is set, returns null.
     * @type int
     */
     getZoomForExtent: function (bounds) {
-        return this.baseLayer.getZoomForExtent(bounds);        
+        zoom = null;
+        
+        if (this.baseLayer != null) {
+            zoom = this.baseLayer.getZoomForExtent(bounds);
+        }
+        return zoom;
     },
 
   /********************************************************/