From 3ed4114f7d3aa14dafe830e50c569438b4b5afcb Mon Sep 17 00:00:00 2001 From: Georg Brandl Date: Fri, 15 Oct 2010 16:19:43 +0000 Subject: #9801: document how list and dict proxies created by Managers behave w.r.t. mutable items. --- Doc/library/multiprocessing.rst | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst index f8327ec..09d6de9 100644 --- a/Doc/library/multiprocessing.rst +++ b/Doc/library/multiprocessing.rst @@ -1284,6 +1284,24 @@ their parent process exits. The manager classes are defined in the Create a shared ``list`` object and return a proxy for it. + .. note:: + + Modifications to mutable values or items in dict and list proxies will not + be propagated through the manager, because the proxy has no way of knowing + when its values or items are modified. To modify such an item, you can + re-assign the modified object to the container proxy:: + + # create a list proxy and append a mutable object (a dictionary) + lproxy = manager.list() + lproxy.append({}) + # now mutate the dictionary + d = lproxy[0] + d['a'] = 1 + d['b'] = 2 + # at this point, the changes to d are not yet synced, but by + # reassigning the dictionary, the proxy is notified of the change + lproxy[0] = d + Namespace objects >>>>>>>>>>>>>>>>> -- cgit v0.12