I have made an experimental implementation of materialized trees for
In a materialized tree, each node contains an explicit path attribute.
This allows for efficient subtree searches [expensive in acts_as_tree]
and insertion and removal of children [expensive in acts_as_nested_set]
This should be considered proof-of-concept rather than production-ready
code. Requires ActiveRecord 2.1.x or later, as it makes extensive use of
Code: git clone git://rubyforge.org/acts-as-matree.git