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pyrex41yesterday at 8:06 PM1 replyview on HN

Shen has some really unique properties that are under-developed here. It's type system itself is Turing complete and very flexible / expressive. Also, the Shen kernel is extremely compact, and easy to port into a wide variety of runtime languages (C, Lisp, Ruby, Python, JS, Go, etc https://shen-language.github.io/#downloads). What I discussed about using it as a compile-time gate + codegen is just scratching the surface, I think.

Now, a lot of the ports haven't been maintained. But the underlying Shen kernel is only 4-5k lines of code...remains extremely portable. More discussion here https://news.ycombinator.com/item?id=39602472

I didn't focus a ton on Shen in the blog post, because the underlying principles aren't really about the implementation. Shen is very cool tho.


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zozbot234yesterday at 8:54 PM

> It's type system itself is Turing complete

That's not a good thing! A Turing complete type system means that compilation is potentially undecidable and non-terminating. The whole unintuitive mess in dependently-typed systems about "definitional" equality (loosely speaking, a notion of equalities that are 'trivially' checked as part of evaluation) is entirely about avoiding Turing-complete type checking!

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