From b24b47e64355224c1bf4e46ed7c4d9f7df4e6f09 Mon Sep 17 00:00:00 2001 From: Jakub Stasiak Date: Wed, 6 Oct 2021 20:23:02 +0200 Subject: [doc] Mention __slots__ behavior in weakref.rst (GH-21061) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It took me longer than I expected to figure out why a random class I dealt with didn't support weak references. I believe this addition will make the __slots__/weakref interaction more discoverable to people having troubles with this. (Before this patch __slots__ was not mentioned in weakref documentation even once). Co-authored-by: Łukasz Langa --- Doc/library/weakref.rst | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Doc/library/weakref.rst b/Doc/library/weakref.rst index 5a8df4c27d..1102c634ed 100644 --- a/Doc/library/weakref.rst +++ b/Doc/library/weakref.rst @@ -88,6 +88,10 @@ support weak references but can add support through subclassing:: Extension types can easily be made to support weak references; see :ref:`weakref-support`. +When ``__slots__`` are defined for a given type, weak reference support is +disabled unless a ``'__weakref__'`` string is also present in the sequence of +strings in the ``__slots__`` declaration. +See :ref:`__slots__ documentation ` for details. .. class:: ref(object[, callback]) -- cgit v1.2.1