Undo/Redo Operations in Complex Environments

During the past thirty years, several types of non-linear undo models have been presented, but almost none of them solves undoing and redoing actions in environments, where multiple history buffers are involved and when there are causal dependencies among separate actions.This paper describes a new model which allows a user to select any action from any history buffer. The key part of the model is a smart command design and an undo manager, which searches for dependencies and offers possible solutions to the user. The results are presented in the context of evolution-management framework called DaemonX.