BTree lengths are too expensive to compute

Objects that use BTrees need to keep track of lengths themselves. This class provides an object for doing this.

As a bonus, the object support application-level conflict resolution.

It is tempting to to assign length objects to __len__ attributes to provide instance-specific __len__ methods. However, this no longer works as expected, because new-style classes cache class-defined slot methods (like __len__) in C type slots. Thus, instance-define slot fillers are ignores.

Base classes

Implemented Interfaces


There are no attributes in this class.


Known Subclasses

There are no known subclasses.