Disco is a pure, strict, statically typed functional programming language designed to be used in the setting of a discrete mathematics course. The goals of the language are to introduce students to functional programming concepts early, and to enhance their learning of mathematics by providing a computational platform for them to play with. It features mathematically-inspired notation, property- based testing, equirecursive algebraic types, subtyping, built-in list, bag, and finite set types, a REPL, and student-focused documentation. Disco is implemented in Haskell, with source code available on GitHub [https://github.com/disco-lang/disco], and interactive web-based REPL available through replit [https://replit.com/@BrentYorgey/Disco#README.md]. |