Scryer Shen article

[mthom]

I describe a few novel features of Scryer Shen in this article I just posted.

If you're not familiar, Shen is a Lisp family programming language with optional static type checking and an integrated Prolog engine. Its static type checker is also implemented in Prolog.

Scryer Shen is a new Shen implementation I'm writing in Racket and Scryer Prolog. Unlike previous Shens, it isn't bootstrapped from provided code written in a much smaller seed Lisp. Consequently it's able to use Scryer Prolog to host its type checker and to serve as its logic engine. The article shows how a handful of Scryer Prolog's features are used to extend the expressive power of Shen's type system exemplified by adding variadic function types to Shen.

[jjtolton]

I've spent a lot of time doing Clojure. I'm a huge fan of Clojure. But I do wish it had optional type checking. Yes, there are many, many, many workarounds for it and yes, if you're a "real Clojure programmer" you can write you code in such a way that "you don't need typing". But it would still be nice, especially for readability and refactoring. The number of times I've come across

(defn handle-response [data] 
    ...)

and been like wtf is data... well it's at least one time too many. It's even worse when you git blame and realize you are the one that wrote it.

I also wish it had a built-in Prolog engine, because writing (and rewriting, and maintaining...) search code in Clojure is -- to me -- not very fun.

Lo and behold!

...Shen is a Lisp family programming language with optional static type checking and an integrated Prolog engine.

Will be very excited to follow this! 🍿 🍿 🍿