Structure Editor for Building Software Models

Abstract: Alloy is well known a declarative modeling language. A key strength of Alloy is its scenario finding toolset, the Analyzer, which allows users to explore all valid scenarios that adhere to the model's constraints up to a user-provided scope. Despite the Analyzer, Alloy is still difficult for novice users to learn and use. A recent empirical study of over 93,000 new user models reveals that users have trouble from the very start: nearly a third of the models novices write fail to compile. We believe that the issue is that Alloy's grammar and type information is passively relayed to the user despite this information outlining a narrow path for how to compose valid formulas. In this paper, we outline a proof-of-concept for a structure editor for Alloy in which user's build their models using block based inputs, rather than free typing, which by design prevents compilation errors.