resholve VS swift-sh

I'm also not 100% on whether it answers the question, but I imagine you're thinking of https://github.com/abathur/resholve (doc in nixpkgs: https://github.com/NixOS/nixpkgs/blob/master/pkgs/development/misc/resholve/README.md)

I intend to eventually find some time to figure out how feasible it would be to use https://github.com/abathur/resholve or wrapper techniques to bolt basalt (and perhaps other bash PMs) on to the nix ecosystem and nix-package some of your libraries.

(I'd love to have this ability for https://github.com/abathur/resholve to reliably identify arguments to one command that are also external commands/programs that it will in turn exec. I can't imagine trying to start it until/unless I have any bright ideas about how that executable spec and a parser for it would work.)

In https://github.com/abathur/resholve/blob/master/default.nix and https://github.com/abathur/resholve/blob/master/shell.nix you can see one approach to extending that line of thought to the default.nix itself.

Completions have in general been of interest, though the shell-specific completions I've looked at so far were all too dynamic.

I'd forgotten all about Fig since I saw your launch post here last year, so thanks for reminder. (I don't think I had quite started to work on parsing specific external commands, yet. Was still focused on just identifying the likely presence of exec in the executables.)

Are you familiar with the parse code? Are you handling painful stuff like combined short flags with a trailing option? (If I ferreted out some of the more painful cases I've had to wrangle, I am curious if you'd have a gut sense of whether your approach handles it. Would you mind if I reach out? I am working on this for https://github.com/abathur/resholve)

@dloreto @robrich A little aside from the announcement, but since it seems like you both work on this I wanted to surface something that came up down in a subthread:

I'm curious if you attempted to support macOS by doing this with Nix's dockerTools and cross-compiling (there may be better sources, but it's at least hinted at in https://nix.dev/tutorials/building-and-running-docker-images...)? If so, I'm wondering where that failed or bogged down?

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Background: I build a tool (https://github.com/abathur/resholve) for ~packaging Bash/Shell (i.e., for demanding all dependencies be present). The tool's technically agnostic, but I built it specifically to fix Shell packaging in Nix.

I think it could benefit a lot of other Shell projects, since one of Shell's big tribulations is dealing with heterogenous environments, but most Shell projects wouldn't see much reason to endure the pain of adopting Nix if they still had to support the heterogenous environments.

Much like you're doing here, I've entertained figuring out how to build a Nix-based packaging flow that can generate deployable standalone bundles or containers. It'd be a heavy way to bundle Shell, but I imagine some projects would take the tradeoff for predictability and reduced support load. But since it would need to take place within a Nix build, I'd need to cross-compile for it to work on macOS. Hoping you know if it's a dead-end or not :)

For a concrete example, I've been developing a tool (https://github.com/abathur/resholve) that can ~build/link Bash/Shell scripts--i.e., rewrite them with external executables converted to absolute paths. (This helps ensure dependencies are known, declared, present, and don't have to be on the global PATH for the script to execute cleanly.)

There's a devilish sub-problem, which is that any given executable can potentially exec arbitrary arguments. For now I handle this with a very crude automated binary/executable analysis that needs to be augmented by human source analysis. Deep multi-language source analysis wouldn't be very scalable, but I suspect fairly-standardized structural annotations could improve the results in a scalable way.

I have to imagine there are other applications of the same information.

I'm not 100% sure if you see the minimal PATH dependencies as a problem or not--so this may or may not help--but I develop https://github.com/abathur/resholve to make it easier to package Shell in Nix/nixpkgs by rewriting invocations of external dependencies in Shell scripts to absolute paths--and shunit2 is one of the Nix packages that I've updated to use resholve.

I came here to say this, too :)

But, of course, it still isn't a silver bullet...

1. You still have to have a sane PATH. A fair amount of the Nix install-related issues that get opened are PATH problems, and you can also run into problems with PATH in cron/launchd.

2. You still have to know what the script depends on. This can get tricky beyond small scripts you wrote yourself. (I write a tool for ~linking/resolving external dependencies in Shell scripts, https://github.com/abathur/resholve. As I've been working on converting some of nixpkgs' existing Shell packages to use it, I almost always find dependencies the initial packager missed.)

Check out resholve. https://github.com/abathur/resholve

Yes, swift CLI will compile and run your swift file.

But many people also want to use libraries. For Python, they use the system libraries or work within an environment with installed libraries (i.e., the library-install process happens at environment-configuration time).

In Swift, the easiest way to consume libraries is using packages, but that requires a Package.swift declaring the project scope for the script file (which must comply with top-level and main-entrypoint code requirements).

The easiest way to do that when scripting is a swift tool that manages the process of gathering your library dependencies, auto-generating a project, building the tool, and caching it all so there's no overhead the next time.

The best available tool now is https://github.com/mxcl/swift-sh. It reads dependency information off import comments.

It can also generate the project for you, if/when you want to build in XCode (e.g., move into a more complex application, perhaps requiring sandbox declarations).

Working scripts are not always updated, so any script-build tool has to maintain backwards compatibility, but the swift package manager has changed a lot in recent versions. swift-sh seems to err on the side of backwards compatibility, and does not support e.g., the most recent dependency versioning styles.

Swift-forum discussions about better support for scripting haven't resulted in any official tooling.

Note that this has nothing to do with the Raspberry Pi. You'll have the same issue running on the command-line. If you wish to test your programs on your computer where you have more tools and horse-power, I find swift-sh gives a good command-line experience and is a great alternative to Playgrounds especially for small tests.