SF #1479988: add methods to allow access to weakrefs for the

weakref.WeakKeyDictionary and weakref.WeakValueDictionary

1 files changed, 48 insertions, 0 deletions

diff --git a/Lib/weakref.py b/Lib/weakref.py
index 09bd0be..4f6d757 100644
--- a/Lib/weakref.py
+++ b/Lib/weakref.py
@@ -118,6 +118,18 @@ class WeakValueDictionary(UserDict.UserDict):
     def __iter__(self):
         return self.data.iterkeys()
 
+    def itervaluerefs(self):
+        """Return an iterator that yields the weak references to the values.
+
+        The references are not guaranteed to be 'live' at the time
+        they are used, so the result of calling the references needs
+        to be checked before being used.  This can be used to avoid
+        creating references that will cause the garbage collector to
+        keep the values around longer than needed.
+
+        """
+        return self.data.itervalues()
+
     def itervalues(self):
         for wr in self.data.itervalues():
             obj = wr()
@@ -162,6 +174,18 @@ class WeakValueDictionary(UserDict.UserDict):
         if len(kwargs):
             self.update(kwargs)
 
+    def valuerefs(self):
+        """Return a list of weak references to the values.
+
+        The references are not guaranteed to be 'live' at the time
+        they are used, so the result of calling the references needs
+        to be checked before being used.  This can be used to avoid
+        creating references that will cause the garbage collector to
+        keep the values around longer than needed.
+
+        """
+        return self.data.values()
+
     def values(self):
         L = []
         for wr in self.data.values():
@@ -263,6 +287,18 @@ class WeakKeyDictionary(UserDict.UserDict):
             if key is not None:
                 yield key, value
 
+    def iterkeyrefs(self):
+        """Return an iterator that yields the weak references to the keys.
+
+        The references are not guaranteed to be 'live' at the time
+        they are used, so the result of calling the references needs
+        to be checked before being used.  This can be used to avoid
+        creating references that will cause the garbage collector to
+        keep the keys around longer than needed.
+
+        """
+        return self.data.iterkeys()
+
     def iterkeys(self):
         for wr in self.data.iterkeys():
             obj = wr()
@@ -275,6 +311,18 @@ class WeakKeyDictionary(UserDict.UserDict):
     def itervalues(self):
         return self.data.itervalues()
 
+    def keyrefs(self):
+        """Return a list of weak references to the keys.
+
+        The references are not guaranteed to be 'live' at the time
+        they are used, so the result of calling the references needs
+        to be checked before being used.  This can be used to avoid
+        creating references that will cause the garbage collector to
+        keep the keys around longer than needed.
+
+        """
+        return self.data.keys()
+
     def keys(self):
         L = []
         for wr in self.data.keys():