command-line-rust VS nushell

You absolutely must write programs, preferably using tests to ensure you are creating correct and reproducible code. May I suggest starting with my book, Command-Line Rust (O'Reilly, 2022). All the code/data/tests are in https://github.com/kyclark/command-line-rust Note that there are branches showing how to use the 4.x version of clap (command-line argument parser) rather than the 2.33 that was current when the book was published.

I think the best way to start learning a programming language is to write lots of small programs that you probably already know. Rust is a perfect command-line language, so I think it makes sense to start by implementing simple programs like "head" and "grep." I also think one should always learn to write and run tests, so I present my GitHub repo of inputs and tests you might like to use to write 14 such standard Unix command-line utilities: https://github.com/kyclark/command-line-rust If you want guidance on the language, I wrote a book called Command-Line Rust (O'Reilly, 2022) that explains all this code. One caveat is that the "clap" (command-line argument parser) module was at 2.33 when I published but is now v4, so you should look at the appropriate branches for versions of the programs that use the "builder" and "derive" patterns for that module. Or just use any old command-line parser you like as there's no requirement to use "clap." Best of luck to you!

You must write programs in a language in order to learn it. I also firmly believe that learning how to write and run tests is critical to learning any language. I wrote Command-Line Rust (O'Reilly, 2022) for the beginner (in Rust, at least) and with a focus on writing and testing small programs from very simple "Hello, world!" and getting increasingly more complex. You can look at https://github.com/kyclark/command-line-rust for the code/inputs/tests. Best of luck!

Code for the above book

I'm the author of Command-Line Rust (O'Reilly, 2022), which I wrote to introduce the language slowly to beginners by writing and testing short, focused programs. You can look over the code/tests/data at https://github.com/kyclark/command-line-rust. Note that there are branches that show the same programs using a more recent version of the "clap" crate.

I wrote Command-Line Rust (O'Reilly, 2022) to guide beginners in the language. You are challenged to write small functions and programs using tests to verify that everything is correct. You can look over the code and tests at https://github.com/kyclark/command-line-rust. Best of luck in your journey!

Here are the example programs from my book, Command-Line Rust (O'Reilly, 2022), along with the input files and tests: https://github.com/kyclark/command-line-rust

I like to suggest that students write programs they already know (or at least understand). For instance, you probably understand that head shows the first few lines of a text file, and you probably can already implement some version of that in one or two languages you know. Try that in Rust. I wrote 14 BSD/GNU command-line utilities in Rust for learning purposes. I wouldn't consider these high-performance/production programs as they are tailored to learning the language. I also stress how to test programs, so there are tests and inputs you can use to verify your programs match the output of the original programs (or you can modify these to suit your own tastes for how you would like them to work). https://github.com/kyclark/command-line-rust

Here are some more examples you may or may not find useful: https://github.com/kyclark/command-line-rust I tend to have a main() that calls a library's run() function that returns a Result and then exit with a nonzero code and error message on a failure.

The first method is through downloading the pre-built binaries. With this method, you don't need to install anything other than Nushell's dependencies. Once you've downloaded the binaries, add them to your system's environment path to run it directly in your terminal.

I rather nushell for this purpose, it's more fun to write and easier to read.

https://www.nushell.sh/

These are just three small examples of what this shell written in Rust allows. The features are many and many more, but I'll leave it up to you to discover and enjoy them; I'm currently playing around with it and it's giving me a lot of satisfaction and immediacy, now it has a fixed place among the tools I use when working! The project is Open Source, so if you want to contribute, I invite you, as always, to do so, I leave you the link to the repo here!

Any thoughts on fish as compared to nushell [0]? It's similar to PowerShell in its philosophy and is also written in Rust.

[0] https://github.com/nushell/nushell

> In PowerShell, structured output is the default and it seems to work very well.

PowerShell goes a step beyond JSON, by supporting actual mutable objects. So instead of just passing through structured data, you effectively pass around opaque objects that allow you to go back to earlier pipeline stages, and invoke methods, if I understand correctly: https://learn.microsoft.com/en-us/powershell/module/microsof....

I'm rather fond of wrappers like jc and libxo, and experimental shells like https://www.nushell.sh/. These still focus on passing data, not objects with executable methods. On some level, I find this comfortable: Structured data still feels pretty Unix-like, if that makes sense? If I want actual objects, then it's probably time to fire up Python or Ruby.

Knowing when to switch from a shell script to a full-fledged programming language is important, even if your shell is basically awesome and has good programming features.

Maybe if the "popular" shells, but http://www.nushell.sh/ is looking better and better

Yeah agreed, especially now that PowerShell is available cross-platform.

Nushell[1] also seems like a promising alternative, but I haven’t had a chance to play with it yet.

[1]: https://www.nushell.sh/

I also discovered an existing discussion[1] related to this topic which includes a link[2] to a "helper to call nushell nuon/json/yaml commands from bash/fish/zsh" and a comment[3] that the current nushell dev focus is "on getting the experience inside nushell right and [we] probably won't be able to dedicate design time to get the interface of native Nu commands with an outside POSIX shell right and stable.".

[0] https://gitlab.com/RancidBacon/notes_public/-/blob/main/note...

[1] "Expose some commands to external world #6554": https://github.com/nushell/nushell/issues/6554

[2] https://github.com/cruel-intentions/devshell-files/blob/mast...

[3] https://github.com/nushell/nushell/issues/6554#issuecomment-...