2 files changed, 21 insertions, 16 deletions
diff --git a/django/template/context.py b/django/template/context.py
index 6ba53f340b..8f16a95021 100644
--- a/django/template/context.py
+++ b/django/template/context.py
@@ -62,6 +62,8 @@ class Context(object):
 
     def update(self, other_dict):
         "Like dict.update(). Pushes an entire dictionary's keys and values onto the context."
+        if not hasattr(other_dict, '__getitem__'): 
+            raise TypeError('other_dict must be a mapping (dictionary-like) object.')
         self.dicts = [other_dict] + self.dicts
         return other_dict
 
diff --git a/django/template/defaulttags.py b/django/template/defaulttags.py
index 01c43ee86f..489faa243e 100644
--- a/django/template/defaulttags.py
+++ b/django/template/defaulttags.py
@@ -157,8 +157,8 @@ class ForNode(Node):
         return nodelist.render(context)
 
 class IfChangedNode(Node):
-    def __init__(self, nodelist, *varlist):
-        self.nodelist = nodelist
+    def __init__(self, nodelist_true, nodelist_false, *varlist):
+        self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false
         self._last_seen = None
         self._varlist = map(Variable, varlist)
         self._id = str(id(self))
@@ -173,20 +173,21 @@ class IfChangedNode(Node):
                 # like an OR evaluation of the multiple variables.
                 compare_to = [var.resolve(context) for var in self._varlist]
             else:
-                compare_to = self.nodelist.render(context)
+                compare_to = self.nodelist_true.render(context)
         except VariableDoesNotExist:
             compare_to = None
 
-        if  compare_to != self._last_seen:
+        if compare_to != self._last_seen:
             firstloop = (self._last_seen == None)
             self._last_seen = compare_to
             context.push()
             context['ifchanged'] = {'firstloop': firstloop}
-            content = self.nodelist.render(context)
+            content = self.nodelist_true.render(context)
             context.pop()
             return content
-        else:
-            return ''
+        elif self.nodelist_false:
+            return self.nodelist_false.render(context)
+        return ''
 
 class IfEqualNode(Node):
     def __init__(self, var1, var2, nodelist_true, nodelist_false, negate):
@@ -363,12 +364,9 @@ class URLNode(Node):
         try:
             return reverse(self.view_name, args=args, kwargs=kwargs)
         except NoReverseMatch:
-            try:
-                project_name = settings.SETTINGS_MODULE.split('.')[0]
-                return reverse(project_name + '.' + self.view_name,
-                               args=args, kwargs=kwargs)
-            except NoReverseMatch:
-                return ''
+            project_name = settings.SETTINGS_MODULE.split('.')[0]
+            return reverse(project_name + '.' + self.view_name,
+                           args=args, kwargs=kwargs)
 
 class WidthRatioNode(Node):
     def __init__(self, val_expr, max_expr, max_width):
@@ -803,9 +801,14 @@ def ifchanged(parser, token):
             {% endfor %}
     """
     bits = token.contents.split()
-    nodelist = parser.parse(('endifchanged',))
-    parser.delete_first_token()
-    return IfChangedNode(nodelist, *bits[1:])
+    nodelist_true = parser.parse(('else', 'endifchanged'))
+    token = parser.next_token()
+    if token.contents == 'else':
+        nodelist_false = parser.parse(('endifchanged',))
+        parser.delete_first_token()
+    else:
+        nodelist_false = NodeList()
+    return IfChangedNode(nodelist_true, nodelist_false, *bits[1:])
 ifchanged = register.tag(ifchanged)
 
 #@register.tag