Fixes #3529 -- more explicit documentation about Context.update. Thanks for the patch, ggetzie.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@14689 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/template/context.py

@@ -74,7 +74,7 @@ class Context(BaseContext):
         super(Context, self).__init__(dict_)
 
     def update(self, other_dict):
-        "Like dict.update(). Pushes an entire dictionary's keys and values onto the context."
+        "Pushes other_dict to the stack of dictionaries in the Context"
         if not hasattr(other_dict, '__getitem__'):
             raise TypeError('other_dict must be a mapping (dictionary-like) object.')
         self.dicts.append(other_dict)

docs/ref/templates/api.txt

@@ -281,6 +281,22 @@ If you ``pop()`` too much, it'll raise
     ...
     django.template.ContextPopException
 
+In addition to ``push()`` and ``pop()``, the ``Context``
+object also defines an ``update()`` method. This works like ``push()``
+but takes a dictionary as an argument and pushes that dictionary onto
+the stack instead of an empty one.
+
+    >>> c = Context()
+    >>> c['foo'] = 'first level'
+    >>> c.update({'foo': 'updated'})
+    {'foo': 'updated'}
+    >>> c['foo']
+    'updated'
+    >>> c.pop()
+    {'foo': 'updated'}
+    >>> c['foo']
+    'first level'
+
 Using a ``Context`` as a stack comes in handy in some custom template tags, as
 you'll see below.