Algorithm::Dependency is a framework for creating simple read-only dependency hierarchies, where you have a set of items that rely on other items in the set, and require actions on them as well. Despite the most visible of these being software installation systems like the CPAN installer, or debian apt-get, they are useful in other situations. This module intentionally uses implementation-neutral words, to avoid confusion. WWW: http://search.cpan.org/dist/Algorithm-Dependency/