Guido explicitly rejects PEP 3142.

pep-3142.txt

@@ -3,12 +3,13 @@ Title: Add a "while" clause to generator expressions
 Version: $Revision$
 Last-Modified: $Date$
 Author: Gerald Britton <gerald.britton@gmail.com>
-Status: Draft
+Status: Rejected
 Type: Standards Track
 Content-Type: text/plain
 Created: 12-Jan-2009
 Python-Version: 3.0
 Post-History:
+Resolution: http://mail.python.org/pipermail/python-dev/2013-May/126136.html
 
 
 Abstract