I’ve been looking around for a scripting language that:
- has a cli interpreter
- is a “general purpose” language (yes, awk is touring complete but no way I’m using that except for manipulating text)
- allows to write in a functional style (ie. it has functions like map, fold, etc and allows to pass functions around as arguments)
- has a small disk footprint
- has decent documentation (doesn’t need to be great: I can figure out most things, but I don’t want to have to look at the interpter source code to do so)
- has a simple/straightforward setup (ideally, it should be a single executable that I can just copy to a remote system, use to run a script and then delete)
Do you know of something that would fit the bill?
Here’s a use case (the one I run into today, but this is a recurring thing for me).
For my homelab I need (well, want) to generate a luhn mod n check digit (it’s for my provisioning scripts to generate synchting device ids from their certificates).
I couldn’t find ready-made utilities for this and I might actually need might a variation of the “official” algorithm (IIUC syncthing had a bug in their initial implementation and decided to run with it).
I don’t have python (or even bash) available in all my systems, and so my goto language for script is usually sh (yes, posix sh), which in all honestly is quite frustrating for manipulating data.
What about Lua/Luajit?
In most scripting languages you have the interpreter binary and the (standard) libraries as separate files. But creating self-extracting executables, that clean up after themselves can easily be done by wrapping them in a shell script.
IMO, if low dependencies and small size is really important, you could also just write your script in a low level compiled language (C, Rust, Zig, …), link it statically (e.g. with musl) and execute that.
I use Lua for this sort of thing. Not my favorite language, but it works well for it. Easy to build for any system in the last 20-30 years, and probably the next 20 too. The executable is small so you can just redistribute it or stick it in version control.