Ticket #2146: regroup.diff

django/template/defaulttags.py

@@ -195 +195 @@
         and_ = 0,
         or_ = 1
 
+class Group(list):
+    def __init__(self, grouper, groups):
+        self.grouper = grouper
+        super(Group, self).__init__(groups)
+
+    def __str__(self):
+        return str(self.grouper)
+
+    # for backwards compatability
+    def __getitem__(self, key):
+        if key == 'list':
+            return self
+        elif key == 'grouper':
+            return self.grouper
+        else:
+            raise KeyError
+
 class RegroupNode(Node):
     def __init__(self, target, expression, var_name):
         self.target, self.expression = target, expression
@@ -205 +222 @@
         if obj_list == '': # target_var wasn't found in context; fail silently
             context[self.var_name] = []
             return ''
-        output = [] # list of dictionaries in the format {'grouper': 'key', 'list': [list of contents]}
+        output = [] # list of Group objects
         for obj in obj_list:
             grouper = self.expression.resolve(Context({'var': obj}))
             # TODO: Is this a sensible way to determine equality?
-            if output and repr(output[-1]['grouper']) == repr(grouper):
-                output[-1]['list'].append(obj)
+            if output and repr(output[-1].grouper) == repr(grouper):
+                output[-1].append(obj)
             else:
-                output.append({'grouper': grouper, 'list': [obj]})
+                output.append(Group(grouper, [obj]))
         context[self.var_name] = output
         return ''
 
@@ -722 +739 @@
         {% regroup people by gender as grouped %}
         <ul>
         {% for group in grouped %}
-            <li>{{ group.grouper }}
+            <li>{{ group }}
             <ul>
-                {% for item in group.list %}
+                {% for item in group %}
                 <li>{{ item }}</li>
                 {% endfor %}
             </ul>
@@ -732 +749 @@
         </ul>
 
     As you can see, ``{% regroup %}`` populates a variable with a list of
-    objects with ``grouper`` and ``list`` attributes.  ``grouper`` contains the
-    item that was grouped by; ``list`` contains the list of objects that share
-    that ``grouper``.  In this case, ``grouper`` would be ``Male``, ``Female``
-    and ``Unknown``, and ``list`` is the list of people with those genders.
+    group objects. The group objects are lists of objects that share the
+    same ``grouper``. group objects behave just like lists, with one
+    exception: the str()-method returns the grouper. In this case, the
+    ```groupers``` would be would be ``Male``, ``Female``
+    and ``Unknown``, and each group is the list of people with those genders.
 
     Note that `{% regroup %}`` does not work when the list to be grouped is not
     sorted by the key you are grouping by!  This means that if your list of