diff -r cf76514ea0c4 -r 396424834902 src/ztfy/utils/decorator.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/ztfy/utils/decorator.py	Fri Jan 17 13:28:22 2014 +0100
@@ -0,0 +1,52 @@
+### -*- coding: utf-8 -*- ####################################################
+##############################################################################
+#
+# Copyright (c) 2008 Thierry Florac <tflorac AT ulthar.net>
+# All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
+# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+# FOR A PARTICULAR PURPOSE.
+#
+##############################################################################
+
+
+# import standard packages
+import functools
+import warnings
+
+# import Zope3 interfaces
+
+# import local interfaces
+
+# import Zope3 packages
+
+# import local packages
+
+
+def deprecated(*msg):
+    """This is a decorator which can be used to mark functions
+    as deprecated. It will result in a warning being emitted
+    when the function is used.
+    """
+
+    def decorator(func):
+
+        @functools.wraps(func)
+        def new_func(*args, **kwargs):
+            warnings.warn_explicit("Function %s is deprecated. %s" % (func.__name__, message),
+                                   category=DeprecationWarning,
+                                   filename=func.func_code.co_filename,
+                                   lineno=func.func_code.co_firstlineno + 1)
+            return func(*args, **kwargs)
+        return new_func
+
+    if len(msg) == 1 and callable(msg[0]):
+        message = u''
+        return decorator(msg[0])
+    else:
+        message = msg[0]
+        return decorator