Visualization of Syntax Trees for Language Processing Courses

This article describes the educational tool VAST. We designed VAST to be used in compiler and language processing courses. The current version allows generating and visualizing syntax trees and their construction process. The main advantages of VAST follow: it is designed to be as independent from the parser generator as possible, it allows students to visualize the behavior of parsers they develop, and it has an interface designed to easily handle huge syntax trees. Finally, we describe two satisfactory preliminary evaluations from the usability and educational points of view.