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.
Why aren’t python and bash be available in all your systems? Which languages would be?
I would’ve recommended python, otherwise perl or Haskell (maybe Haskell’s too big) or something, but now I’m worried that whatever reason makes python undoable also makes perl etc. undoable
Mate, I came on here to post Haskell as a semi-ironic ‘joke’ and it’s included in the top comment. You’ve made my day.
I mean, it’s a functional programming language and an incredibly good one. But it probably has a far too big footprint for their use-case…
Oh, I know. I adore Haskell.
Why aren’t python and bash be available in all your systems?
Among others, I run stuff on alpine and openwrt.
I don’t need to run these scripts everywhere (strictly speaking, I don’t need the homlab at all), but I was wondering if there’s something that I can adopt as a default goto solution without having to worry about how each system is packaged/configured.
As for python, I doubt the full version would fit in my router plus as said I don’t want to deal with libraries/virtualenvs/… and (in the future) with which distro comes with python3 vs pyton4 (2 vs 3 was enough). Openwrt does have smaller python packages, but then I would be using different implementations on different systems: again something I’d rather not deal with.
As for perl, it would be small enough, but I find it a bit archaic/esoteric (prejudice, I know), plus again I don’t want to deal with how every distro decides to package the different things (eg. openwrt has some 40+ packages for perl - if I were doing serious development that would be ok, but I don’t want to worry about that for just some scripts).
Sounds like you want MicroPython. It’s definitely available on OpenWrt and AlpineLinux and has a very small footprint.
If you don’t like Python, have a look at Lua/luajit.
You’ve defined yourself into an impossible bind: you want something extremely portable, universal but with a small disk imprint, and you want it to be general purpose and versatile.
The problem is that to be universal and general purpose, you need a lot of libraries to interact with whatever type of systems you might have it on (and the peculiarities of each), and you need libraries that do whatever type of interactions with those systems that you specify.
E.g. under-the-hood, python’s
open("", 'r')is a systemcall to the kernel. But is that Linux? BSD? Windows NT? Android? Mach?What if you want your script to run a CLI command in a subshell? Should it call “cmd”? or “sh”? or “powershell”? Okay, okay, now all you need it to do is show the contents of a file… But is the command “cat” or “type” or “Get-FileContents”?
Or maybe you want to do more than simple read/write to files and string operations. Want to have graphics? That’s a library. Want serialization for data? That’s a library. Want to read from spreadsheets? That’s a library. Want to parse XML? That’s a library.
So you’re looking at a single binary that’s several GBs in size, either as a standalone or a self-extracting installer.
Okay, maybe you’ll only ever need a small subset of libraries (basic arithmetic, string manipulation, and file ops, all on standard glibc gnu systems ofc), so it’s not really “general purpose” anymore. So you find one that’s small, but it doesn’t completely fit your use case (for example, it can’t parse uci config files); you find another that does what you need it to, but also way too much and has a huge footprint; you find that perfect medium and it has a small, niche userbase… so the documentation is meager and it’s not easy to learn.
At this point you realize that any language that’s both easy to learn and powerful enough to manage all instances of some vague notion of “computer” will necessarily evolve to being general purpose. And being general purpose requires dependencies. And dependencies reduce portability.
At this point your options are: make your own language and interpreter that does exactly what you want and nothing more (so all the dependencies can be compiled in), or decide which criteria you are willing to compromise on.
Is compiling scripts an option? Aka compiling them in C, C++, Rust, whatever for your router on another machine, and copying and executing those binaries on your router?
if there’s something that I can adopt as a default goto solution without having to worry about how each system is packaged/configured.
Go is probably your best bet. Simple to use, and you can compile it so it runs everywhere
luajitis small, fast(well, it can jit), and has a small but complete standard library and can do FFI pretty easily, should be ideal for most homelab usecaseldd $(which luajit) linux-vdso.so.1 (0x00007ffee9dc7000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fb4db618000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fb4db613000) libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007fb4db5f3000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fb4db3ca000) /lib64/ld-linux-x86-64.so.2 (0x00007fb4db799000)
Python is what you want. You can install it on just about any system.
Other than that maybe Lua but that will be hell.
Python is what you want. You can install it on just about any system.
Perl and bash are already there, no need to install anything.
Perl isn’t normally preinstalled by Python is. (On Linux)
Try it now - go on. Type “perl” and tell me what you get.
And if you’re so certain it’s not used, try removing it and see how well your computer works afterwards.
Welp, can’t argue with that
If you just run perl it will sit waiting for input. Try perl --version
It isn’t installed
I know that because I installed it as it was a dependency of Buildroot.
Edit: My bad I must of been thinking about a Perl library
Once git no longer depends on it, it’ll be gone from my system
Um, exactly the opposite on all the distros I use. All Enterprise Linux distros, Suse and Debian.
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.
Micropython.
That does seem to be just one, maybe two small files, and no dependencies. And a built in map() function.
i use mostly python and lua.
Lua
Shutters
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)
I honestly love Powershell, but haven’t tried the Linux version yet. I only use Bash on linux but it has a load of odd quirks that make it unpleasant to use imo. Can’t comment on anything else.
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?
OP is on OpenWRT
Fair point - I missed that, buried in the comments as it was.
In that scenario, you use what’s available, I guess.
OP said they just want to copy a binary around. Can you do that with perl?
This is linux. Someone will have done it.
I’ve looked into this a lot actually. There see many options. I’ll highlight the pros and cons of each option.
Lua: extremely lightweight, but standard library is lacking, and doesn’t include stuff like map or fold. But that would be easy to fix.
Python: thicc standard library, but is not lightweight by any means. There are modifications made to be more shell like, such as xonsh
Rash: based on scheme, very much functional but if you’re not used to lisp style, might take a bit to get used to it. This is actually my favorite option. It has a cli interpreter, and really pleasant to use. Cons is… Well it’s not very common
You can honestly use any language. Even most compiled languages have a way to run immediately.
No one has mentioned PHP yet? Man, times really have changed.
I used it for scripting a decade after everyone else, but even I have to admit PHP is rarely the best choice now.
I’ve actually tried using PHP on OpenWRT and embedded before. It’s not exactly lightweight, it’s a memory and CPU hog. Keep in mind that the kind of machine that runs OpenWRT might only have 32 or even 16 MB of RAM to work with.
Also, PHP is not the first language that comes to mind when doing data processing and/or functional programming. You can but it doesn’t lend itself well to it.
For data processing?
Yeah, it’s really flexible when it comes to arrays and string processing. Super easy to work with, too.
JavaScript through Node.js, or TypeScript through Deno if you like typed languages. They both check all your boxes (just check the size of the executables to make sure that it’s what you would consider “small footprint”).
Both languages and runtimes are quite popular, so you will find any answers on StackOverflow.
They are both single-executable with little dependencies, and Deno can also compile your scripts to self-contained executables.
As a bonus, both support the vast and extensive NPM package repository where you can find all sort of libraries for even the most complex tasks.
And they work with your favourite IDE or editor, not just syntax highlighting, but also contextual suggestions.
Installing node uses some 60MB (according to zypper on my current desktop). I’d rather have something small and possibly that consists of a single executable.
As a bonus, both support the vast and extensive NPM package repository
That’s not necessarily a feature :) Package repos are great if you are a developer (I am one) working primarily with that language, but are frustrating if you just want to run things.
I thought so. Although almost nothing for modern standards, 60MB is not exactly tiny. Sorry about that.
On a different note, a repository is always a good thing imho. If you’d rather not have to worry about the dependency-pull step you can always include the dependencies with your sources, or just limit your code to using features included in the standard library.
As a Java developer, and someone who never learned Python or other scripting languages, Node is my go-to scripting language. I’ve only come around to it for that in the past year or two. But it’s great.
Not quite a scripting language, but I highly recommend you check out cosmo for your usecase. Cosmopolitan, and/or Actually Portable Executable (APE for short) is a project to compile a single binary in such a way that is is extremely portable, and that single binary can be copied across multiple operating systems and it will still just run. It supports, windows, linux, mac, and a few BSD’s.
— this is where you can download precompiled binaries of certain things using cosmo.
From my testing, the APE version of python works great, and is only 34 megabytes, + 12 kilobytes for the ape elf interpreter.
In addition to python, cosmopolitan also has precompiled binaries of:
And a few more, like tclsh, zsh, dash or emacs (53 MB), which I’m pretty sure can be used as an emacs lisp intepreter.
And it should be noted these may require the ape elf interpeter, which is 12 kilobytes, or the ape assimilate program, which is 476 kilobytes.
EDIT: It also looks like there is an APE version of perl, and the full executable is 24 MB.
EDIT again: I found even more APE/cosmo binaries:
I still love bash. I’m able to accomplish quite a lot with it. I vote bash.
Bash? On windows it’s pretty much unusable even if you use cygwin. Python or Lua are the only reasonable suggestions here
I just assumed the scripts would run on Linux.
Nah, gross. You need to set a bunch of global options to get sane behavior on errors.
Nushell is shaping up really really nicely, and it’ll actually stop executing if something fails! Even if that happens in a pipe! And it’s not super eager to convert between arrays and strings if you use the wrong cryptic rune.
A scripting language written in Rust would certainly fulfill you requirement of only needing to copy one file since they are always statically linked and you can even statically compile against musl so it will work on any Linux system without needing a correct libc. Maybe check out rhai.