VisAST: Generic AST Visualiser for Software Language Education

Abstract

Structural concepts such as abstract syntax trees (ASTs) are often best explained through visual representations. Students may, however, struggle with connecting such visual representations with the corresponding program text. To bridge this gap, we developed visAST, a tool for easily visualising ASTs of small languages written in Haskell. To assess the benefits and usability of visAST we conducted a user study in the context of students implementing interpreters. Students reported liking visAST and it being beneficial for learning. The experiment’s results were not conclusive, but hint at visAST use improving students’ performance.