This video demos a prototype that Max Boksem and I built to investigate a modular graph structure for representing and running source code. The tool allows you to create different projections out of the code such as code structure, documentation view, and execution history. The tool supports incremental and exploratory programming (multiple execution sessions) and "nested graphs" (importing a graph as a node) for hierarchical views. The work was presented at Splash earlier. See the paper here. @Konrad Hinsen, this is the video I promised you a while ago.

Very nice! Graphs can indeed unify many different projections that have traditionally been assumed as the default. This might work much better if we had excellent keyboard-based graph manipulation tools. That's one reason why text continues to dominate.