Show HN: Cicada – A scripting language that integrates with C

The for loop is odd. Why is the word counter in there twice?

    counter :: int

    for counter in <1, 10-counter> (
       print(counter)
       print(" ")
    )

    backfor counter in <1, 9> print(counter, " ")

Cool, I like these kinds of projects. When it comes to embedding a scripting language in C, there are already some excellent options: Notable ones are Janet, Guile, and Lua. Tcl is also worth considering. My personal favorite is still Janet[0]. Others?

[0]: https://janet-lang.org/

The "aliases not pointers" approach for memory safety is interesting. Curious how you handle the performance implications - traditional aliasing analysis in compilers is expensive because determining whether two aliases point to the same memory is hard.

Are you doing this at runtime (reference counting or similar), or have you found a way to make the static analysis tractable by restricting what aliasing patterns are allowed?

The 250kB size is impressive for a language with inheritance and N-dimensional arrays. For comparison, Lua's VM is around 200-300kB and doesn't include some of those features. What did you have to leave out to hit that size? I assume no JIT, but what about things like regex, IO libraries, etc?

Also - calling back into C functions from the script is a key feature for embeddability. How do you handle type marshalling between the script's type system and C's? Do you expose a C API where I register callbacks with type signatures, or is there reflection/dynamic typing on the boundary?

Thanks for the references! Writing a language was almost an accident — I worked on a neural networks tool with a scripted interface back around 2000, before I’d ever heard of some of these other languages.. and I’ve been using/updating it ever since.

Beyond NNs, my use case to embed fast C calculations into the language to make scientific programming easier. But the inspiration was less about the use case and more about certain programming innovations which I’m sure are elsewhere but I’m not sure where — like aliases, callable function arguments, generalized inheritance, etc.

That’s a great list — most of those languages I’ve honestly never heard of..

Can I call into the interpreter from multiple threads or does it use global state?

What's the use case? Clearly, you made it with some specific use in mind, at least initially. What was it?

I've lost count of projects called Cicada