Added experiments

experiments/callableweakref.py

@@ -0,0 +1,52 @@
+import types
+import weakref
+
+
+def ref(function):
+    return CallableWeakReference(function)
+
+
+class CallableWeakReference(object):
+
+    def __init__(self, function):
+        'Create a weak reference to a callable'
+        try:
+            if function.im_self:
+                # We have a bound method or class method
+                self._reference = weakref.ref(function.im_self)
+            else:
+                # We have an unbound method
+                self._reference = None
+            self._function = function.im_func
+            self._class = function.im_class
+        except AttributeError:
+            try:
+                function.func_code
+                # We have a normal function or static method
+                self._reference = None
+                self._function = function
+                self._class = None
+            except AttributeError:
+                function = function.__call__
+                # We have a class masquerading as a function
+                self._reference = weakref.ref(function.im_self)
+                self._function = function.im_func
+                self._class = function.im_class
+
+    def __call__(self):
+        if self.dead:
+            return
+        if self._reference:
+            # We have a bound method
+            return types.MethodType(self._function, self._reference(), self._class)
+        elif self._class:
+            return types.MethodType(self._function, None, self._class)
+        else:
+            return self._function
+
+    @property
+    def dead(self):
+        if self._reference and not self._reference():
+            # We have a bound method whose parent reference has died
+            return True
+        return False