Visual Debugging Technology with Pencil Code — Cali Stenson

Cali and his team have made PencilCode: a tool to help students to debug, in a few ways:

Add the state of variables to lines, allowing users to step forwards and backwards in time, and overlaying the code with arrows to visualiza control flow.

2015-10-22 13.33.11

Really nice work. Cali ended with some challenges. Firstly, how to make this appealing? Cali tried it with some students, but they still did not use it 🙁 How to convince students that this really helps? There are technical challenges too: for example rewinding graphical state.

The paper is available.