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.
There’s always nushell. It’s fairly new, not quite to 1.0 yet (0.96.1 at time of writing), but the constant breaking changes seemed to have stopped. It hits all your points and it’s quite fun to use when writing scripts. Bonus that it’s also pretty much tailor-made to manipulate data.
I don’t know if it matches your desire for easy install of small disk space, but it might make up for it in other arenas - Ruby is my new-found love when making simple scripts. Being able to mostly emulate the shell integration that bash has by just using backticks to call a shell command is the killer feature in my book.
Technically, you could bundle a Perl script with the interpreter on another system using
ppand run the packed version on systems with no installed Perl, but at that point you might as well just use a compiled language.guile scheme or Julia
Neither of them seem to be a single file, and both seem to have several dependencies, at least that’s the case with the Homebrew versions.
@gomp I like TypeScript.
I used Python for 15 years or so until they changed from v2 to v3. At that point I realised I couldn’t understand my old code because it lacked types, so I got discouraged with that. So rather than learn v3 I stopped using it.
Perl is a disaster. sh is good for shell scripts but let’s not stretch it.
TypeScript can use all the JS libraries and runs on node which is supported by all sorts of platforms. Yes there are a few holes in the type safety, so don’t do that.
The internet is full of “how to do X in JS”. You can read them and add the types you need.
I can’t really think of anything that’s less frustrating than sh and ticks all your boxes. You can try TCL but it’s bound to be a shit show. It was painful to use two decades ago.
Perl is a step up in terms of developer comfort, but it’s at the same time too big and too awkward to use.
Maybe a statically linked Python?
I was thinking about recommending TCL as a joke. My favorite thing about it is it’s “whimsicly typed.”
Perl is a step up in terms of developer comfort, but it’s at the same time too big and too awkward to use.
How do you mean?
It’s already on nearly every distro, so there’s no core size unless you lean into modules. The scripts aren’t exactly big either.
He doesn’t have bash. I’m not sure I’ve seen a system this millennium with Perl but not bash.
Try it now - type perl. It’s a dependency on a huge amount of core system tools.
OP is on OpenWRT (a router distro), and Alpine. Those distros don’t come with very much by default, and perl is not a core dependency for any of their default tools. Neither is python.
Based on the way the cosmo project has statically linked builds of python, but not perl, I’m guessing it’s more difficult to create a statically linked perl. This means that it’s more difficult to put perl on a system where it isn’t already there, and that system doesn’t have a package manager*, than python or other options.
*or the the user doesn’t want to use a package manager. OP said they just want to copy a binary around. Can you do that with perl?
Micropython.
That does seem to be just one, maybe two small files, and no dependencies. And a built in map() function.
Maybe something like Elvish or Nushell could be worth a look. They have a lot of similarities to classic shells like bash, but an improved syntax and more powerful features. Basically something in between bash and Python. Not sure about disk footprint or general availability/portability though
Python.
Just remember to use pyenv for interpreter installation, version and environment management. It’s pretty straightforward that way and you have predictability.
Don’t ever manually fiddle with the system python and/or libraries or you’ll break your system. You should just rely on the package manager for that.
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.
If you can, just use Perl. Probably installed on your systems, even the ones without python.
So often the right answer, perl. It’s a shame that it’s so unfashionable these days.
another vote for Lua – lua5.4 is available for all 8 Alpine architectures, tiny installed size (120–200 kB) (and Alpine package only installs two files)
posix sh + awk for manipulating data?
Perl is already installed on most linux machines and unless you start delving into module usage, you won’t need to install anything else.
Python is more fashionable, but needs installing on the host and environments can get complicated. I don’t think it scales as well as Perl, if that’s a concern of yours.
Why not give (Common)LISP a try?
