Example-driven software language engineering

Language workbenches---tools to define software languages together with their IDEs---are designed to simplify language engineering and implementation: they free language engineers from many meticulous tasks, but oftentimes have a very steep learning curve even for experienced software professionals. With the assumption that meta-definitions are one of the key factors that hinder language engineering, we introduce an example-driven approach to language definition. We describe in this paper our vision of a web-based tool aimed at beginner language engineers, and list possible requirements for such a tool. A language is defined by giving examples of code written in it using illustrative syntax definition. These examples are then annotated to specify different concerns of language definition---abstract syntax, typing rules, validation rules, formatting rules, and dynamic semantics.