What Building a DSL Teaches Us About Constraints

I’ve been working on a domain-specific language for a point-and-click framework called Escoria built on top of the Godot game engine . The original DSL was implemented as a regular language, largely using regular expressions. It was flexible in the sense that it accepted a wide range of inputs, but that flexibility came at a cost. There were very few meaningful constraints. As a result: pre-compilation validation was limited runtime behaviour was harder to reason about error handling was brittle