TQL: a case study of integrating DSL in a product

Domain-specific languages power numerous modern applications and libraries, including but not limited to: Wolfram Alpha, Microsoft Excel, Graphviz. This work aims to share the experience gathered from developing TQL (Talisman Query Language) – a domain-specific language used in Talisman platform. Talisman platform is a set of tools to automate data processing tasks, developed by Ivannikov Institute for System Programming of RAS. TQL implementation, discussed in this article, supports error-recovery, can be run directly inside a browser as well as on a server, and it also has an interactive playground that visualizes the parse tree while typing. This article describes several techniques and technologies that were used to make these qualities possible while keeping a single, maintainable codebase.