this post was submitted on 02 Sep 2023
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why?

Because bash feels clunky to write and work with for anything non-trivial, especially compared to other scripting languages.

Why not another scripting language (no compile necessary)?

Because bash and sh are installed nearly everywhere. Any other scripting language means the user is required to have that installed, and that is far less likely to be the case.

If I could write my scripts in a nice syntax, but be sure my users will be able to use it effortlessly by distributing to them compiled versions, then that would make both of our lives easier!

Thoughts? Are there any languges that do this?

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[–] [email protected] 54 points 1 year ago* (last edited 1 year ago) (7 children)

I write a lot of bootstrapping scripts, and I have a solution thats probably something you and others in this thread have never seen before. You can write a single script in a full/normal language, no compilation step, and it works on systems that only have bash/sh. It doesn't compile to bash, or at least not in the way you might think/expect it to, but it should do what you want.

(guillotine because it's a universal executor) https://github.com/jeff-hykin/deno-guillotine

This^ one uses Deno/JavaScript, but in principle it might be possible to do with other languages. It definitely requires some explanation, so I'll try to give that here;

As another person said, shells are not nearly as standardized as we need them to be. Mac uses zsh, Ubuntu uses dash, neither store a posix bash exectuable in the same place, and both have ls and grep differences that are big enough to crash common scripts. Even if you're super strict on POSIX compliance, common things will still break if you write a big script (or trying to compile a big program to bash).

I hate JS as much as the next guy, but it is possible to write a single text file that is valid bash/dash/zsh/powershell and valid JavaScript all at the same time. It sounds impossible, but there is enough overlapping syntax that actually any javascript program can be converted into a valid bash script without mangling the JS code. It might be possible to do for python as well.

POSIX is good enough for making a small, carefully-crafted well-tested OS-detecting caveat-handling script. So that's exactly what we do; use a small shell script at the top to ensure that the JS runtime you want is installed (auto install if missing). Then the script executes itself again using the JS runtime. It wasn't easy but I a made a library that explains how it's possible and gives a cli tool that automates it for the Deno runtime (the link I posted above).

After that, I just recreated tools that feel like bash, but this time they are actually cross platform. Ex:

let argWithSpaces = "some thing"
run`echo hello ${argWithSpaces}`

I picked Deno because it auto installs libraries (imports directly from URL so users don't have to install anything)

[–] aport 44 points 1 year ago (2 children)

its possible to write a single text file that is valid bash/dash/zsh/powershell and valid JavaScript all at the same time. It sounds impossible, but there is enough overlapping syntax that actually any javascript program can be converted into a valid bash script without mangling the JS code.

I'm both impressed and horrified

[–] UlrikHD 25 points 1 year ago* (last edited 1 year ago) (1 children)

It'd honestly the funniest thing I've read on this instance. Puts programmer humour to shame. Love it when developers finds the jankiest/unconventional way to solve problems.

[–] Mikina 2 points 1 year ago* (last edited 1 year ago)

It's one of those tools that can both be used on a resume or as a diagnosis. I love it!

[–] [email protected] 2 points 1 year ago

Agreed hahaha. I thought I'd enjoy the day my code golf skills would be used to solve a legit problem but instead it just feels kinda gross 😆

Honestly it's really dissapointing we don't just have an agreed-upon universal pre-installed language. And it's beyond ironic (more like the universe is laughing at us) that JS, the web language that gets used for every not-web-thing, is also the language with a syntax that allows it to become the effectively universal no-preinstall language.

[–] [email protected] 16 points 1 year ago

Okay at first I was pretty convinced that this was just the wrong way to accomplish what I thought your goal was. But now, after reading the StackOverflow post and your README, I think this is fascinating and frankly really awesome. What a clever and strange thing, using multiline comments that way, and string no-ops. I think just knowing this exists will cause me to find reason to use it.

[–] snowe 12 points 1 year ago (1 children)

Not only do you solve the problem op is trying to solve, but you also made the most horrifying and hilariously ingenious thing at the same time.

[–] [email protected] 3 points 1 year ago

Polyglot runtime lmao

[–] onlinepersona 12 points 1 year ago (1 children)

Bro, make a video and put it up on peertube please then link it in the README. I need to see this shit in action. It sounds awesome, but it's 10am and my eyes are just opening, so reading through everything and testing it isn't happening on my phone rn.

[–] [email protected] 3 points 1 year ago (1 children)

Actually I've been thinking of starting a Youtube/Peertube channel for a while so this will be a good place for me to start!

I'll come back and post a response once I've uploaded it! It'll probably take a week or two.

[–] onlinepersona 1 points 1 year ago

💖 looking forward to it!

[–] Mikina 2 points 1 year ago (1 children)

Do I understand it right that what the tool does is include install scripts in all of the other languages, that simply download a portable Deno runtime and then run the rest of the file (which is the original Javascript code) as Javascript?

So, you basically still have an install step, but it was just automated to work cross-platform though what's basically a polyglot install script. Meaning that this could probably be done with almost any other language, assuming it has a portable runtime - such as portable python and similar, is that correct?

[–] [email protected] 3 points 1 year ago* (last edited 1 year ago)

Almost, but you bring up an important point about other language support.

The code includes an install script for one language, and the second part about "any language" isn't quite right. There is an alternative way to get any-language support but the current approach requires a language to have a syntax that is compatible with bash/powershell. For example I abuse the hell out of multi-line strings and multi line comments in javascript to make it be interpreted as a do-nothing bash/powershell script.

Python specifically might be possible because of its triple-quote strings, I haven't spent a long time trying but I did try a bit. However in general I don't think languages, like Haskell or Elixr, can work in this form because their syntax is incompatible.

However, if you don't care about being able to edit the script, it should be possible to mangle code from other languages, like converting Haskell code to hex or some other escaped format (can't be binary because that's not valid bash/powershell). We'd need to handle unpacking that hex with shell/powershell, but it could be done. And in that case, yes it would work with any portable language. (And many are more portable than Deno, which struggles to run on old stuff like Ubuntu 16.04!)

If you're interested in the hex unpacking let me know. I'm working on an offline bootstrapping script for deno, which involves embedding the runtime binaries of all OS's as hex into the script itself. Once I make it, it should be a lot easier to get this kind of thing working for other portable runtimes.

[–] [email protected] 2 points 1 year ago (1 children)

Can this thing run complied WASM? Because compilers to WASM from other languages exists already

[–] [email protected] 4 points 1 year ago* (last edited 1 year ago)

It can run compiled wasm! So you could write a bootstrap script in rust, compile it to wasm, embed that wasm into a deno installer script using https://deno.land/x/binaryify and then ship that as a universal executor.

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago)

This is absolutely cursed and brilliant. Bravo!

Now I just need to find a place to use it.