Janet is nice, but the ecosystem is too small. I’ve actually uninstalled it from my Macs recently because I ended up not using it, whereas I can take any C and Lua library and do something with Fennel.

The only real issue with Fennel is luarocks—the experience of adding new libraries (or general dependency management) to a (Lua) project is still gnarly.

Janet has a way to break into REPL, but AFAIK no way to restart (a la condition system).

Fennel has something a bit more robust (assert-repl) and it can restart, but can only return a single value from the REPL, which often creates more errors downstream.

It's been a couple years but I think janet has the primitives for this in the netrepl module which I think is part of the standard library. I remember being really surprised at how much introspection and control over the env when you responded to a repl connection, just at that time no one had put it together into what you want. I also seem to remember the actual janet repl being a different implementation which always seemed weird to me.

Any reference for this? The docs[1] don't seem to have much of anything.

[1]: https://janet-lang.org/api/spork/netrepl.html

Yeah that standard lib extension has always been extremely underdocumented.

I thought I remembered being able to manipulate the env as a dynamic which I think could get you what you need. But reading the source now I guess not? I'm pretty out of practice reading janet.

it has the opposite of the numeric tower – numbers are floats. (ugh)