[Zope] Warning: don't refresh MonkeyPatches

Dieter Maurer dieter@handshake.de
Sat, 22 Mar 2003 22:24:00 +0100

Paul Winkler wrote at 2003-3-21 12:47 -0500:
 > Posting this on the off chance that it saves someone the week
 > of hair-tearing that I've just experienced...
 > I sometimes find MonkeyPatches a convenient way to globally change 
 > behavior of zope or 3rd-party products. But I just discovered
 > something very important:
 > it's apparently NOT safe to "refresh" a MonkeyPatch-style product.
 > I have a monkeypatch that works fine until I refresh it, then I get
 > mysterious errors like "Object of type 'None' is not callable" with no
 > indication in the traceback of what object is None or even what's 
 > trying to call it!
 > In a debugging session, I explored everything near the end of the 
 > traceback and could not find any variables that are None. I know
 > it's in there somewhere...

This is not a problem of monkey patching, but of refreshing
in general.

Search the mailing list archives: Shane explains in some
message why it happens and how to avoid it.