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Show HN: Cicada – A scripting language that integrates with C
I wrote a lightweight scripting language that runs together with C. Specifically, it's a C library, you run it through a C function call, and it can callback your own C functions. Compiles to ~250 kB. No dependencies beyond the C standard library.

Key language features: * Uses aliases not pointers, so it's memory-safe * Arrays are N-dimensional and resizable * Runs scripts or its own 'shell' * Error trapping * Methods, inheritance, etc. * Customizable syntax

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

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/

Thanks! I’m unfamiliar with Janet but I’ve looked into the others you listed.

One personal preference is that a scripting syntax be somewhat ‘C-like’.. which might recommend a straight C embedded implementation although I think that makes some compromises.

Io is nice (Smalltalk/Self-like). A mostly comprehensive list: https://dbohdan.github.io/embedded-scripting-languages/
Should have replied directly —- thanks! That’s a great list..
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..

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What's the use case? Clearly, you made it with some specific use in mind, at least initially. What was it?
To be more specific (see my general comment), I’ve used the language in two open-source projects: 1) a chromosome conformation reconstruction tool, and 2) a fast neural network generator (back end). Re Project 2: I’m also planning to embed the language into results webpages served from the NN generator website.