switched back to explicit set for assignments.  {% foo = 42 %} becomes {% set foo = 42 %} and {% foo.something() }} becomes {{ void(foo.something() }} with this commit.

--HG--
branch : trunk
diff --git a/jinja2/defaults.py b/jinja2/defaults.py
index e124930..62dfda2 100644
--- a/jinja2/defaults.py
+++ b/jinja2/defaults.py
@@ -25,7 +25,8 @@
 DEFAULT_NAMESPACE = {
     'range':        xrange,
     'dict':         lambda **kw: kw,
-    'lipsum':       generate_lorem_ipsum
+    'lipsum':       generate_lorem_ipsum,
+    'void':         lambda *a: u''
 }