I am pleased to announce Algebraic Racket, an extension for algebraic structures in untyped Racket.
https://github.com/dedbox/racket-algebraic Algebraic structures provide the operational under-pinnings for algebraic data types. What's missing is the static typing constraints. The initial release provides a #lang algebraic/racket/base that extends #lang racket/base with: 1. First class, lexically scoped, naturally ordered data constructors. > (data Maybe (Just Nothing)) > (define maybe (function* [(n _ Nothing) n] [(_ f (Just x)) (f x)])) > (maybe #f values (Just 123)) 123 > (maybe #f values Nothing) #f 2. A consistent destructuring syntax for functions and macros. > (define fib (function [n #:if (< n 2) 1] [n (+ (fib (- n 1)) (fib (- n 2)))])) > (map fib (build-list 7 values)) '(1 1 2 3 5 8 13) > (define-syntax m-fib (macro [n:nat #:if (< (var n) 2) 1] [n:nat (+ (m-fib #,(- (var n) 1)) (m-fib #,(- (var n) 2)))])) > (list (m-fib 0) (m-fib 1) (m-fib 2) (m-fib 3) (m-fib 4) (m-fib 5) (m-fib 6)) '(1 1 2 3 5 8 13) The package is fully documented. The documentation includes the first of three tutorials in a series on building interpreters with Algebraic Racket. Algebraic Racket is the first major milestone in a larger effort to produce a complete language-oriented toolkit for integrating algebraic structure into more sophisticated designs. The project aims to: 1. Implement and document the forms, functions, and syntax classes comprising Algebraic Racket for maximum potential reuse. 2. Support the development of modular type systems and other language-facing components as libraries. Pull requests of any size are welcome. For major changes, please start a conversation on racket-users or open an issue to discuss what you would like to change. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
