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[RustScript2025]

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[DebianFanatic]

Not a programmer, but I tinker. Consider me an absolute beginner.

I think the README needs to clarify that RustScript is a web-scripting language, not a shell-scripting language. I came here with the idea that RustScript was going to be a better scripting language than bash, NuShell, zsh, Powershell, Python, etc. But the opening pages of the tutorial seem to indicate this is for web use, not shell use.

Okay, I'm wiling to learn, so I'll keep going down this path a bit.

I already had Rust installed (as mentioned, I tinker), but it was several versions old, and when I went to "rustup update", I ran into an issue with some piece of it being deprecated, and whereas the on-screen instructions told me what to do to fix it, it still took me a bit to actually fix it because those instructions kind of assume the user knows more than I do. Nevertheless, I got it figured out, and I'm now at:

kent@westk-9463:~/Downloads/tmp/RustScript/rustscript-learning$ rustc --version rustc 1.91.1 (ed61e7d7e 2025-11-07) kent@westk-9463:~/Downloads/tmp/RustScript/rustscript-learning$

I have no idea if this is ...

with Edition 2024 support.

or not, nor how to determine that.

I was able to do the cargo install wasm-pack without any real difficulty, but probably only because I had some vague idea of wasm from tinkering (quite unsuccessfully) with wasm+Rust a year or so ago. Any greener than I am, and I doubt I would have noticed that requirement (even though it's plainly labeled a requirement) nor would I have understood cargo-based installation.

Thinking the README is the best place to start, I continued reading, and soon got lost in details that a newbie probably doesn't need yet to be exposed to. I was quickly getting lost, but then I found the Complete Tutorial link under the Learning RustScript heading. Ah! Perhaps this is the best place to start.

Okay, I have satisfied the Prerequisites (except possibly for the with Edition 2024 support).

I was able to clone the repository, but only because I spent a week or so last summer trying to wrap my head around git, and sort of kind of understand it, but not comfortably so - I don't "feel" like I understand it, and I instead feel like if I try to use it, I'm going to mangle stuff up.

I had no idea where I'm supposed to git-download this repository to, so I defaulted to my "Downloads" folder, making a "tmp/RustScript" folder within that, into which I git-downloaded.

Sort of being familiar with git, but not really, I was pleasantly tickled to see a clone of github.com's RustScript file structure, and then realized I probably should have expected that result instead of being mildly surprised by it. Like I say, I don't really understand git yet; I reckon I'm just dense in this area (but quite bright in others; call it a mental block).

I was able to cd RustScript and cargo build --release, which I understood well enough from my previous tinkering with Rust. I then thought maybe the resulting executable should be moved into my path, so I cp target/release/rjsc ~/bin, thinking that the rest of this cloned repository, being in a tmp directory, would probably soon be, if not already, ready to be deleted, now that the desired executable had been created. I later realized that was a useless move (at least for the next little bit of the tutorial), and later deleted that copy.

I at first tried to create my first RustScript program in my usual ~/projects directory, but running into a problem, I decided I better try to stick closer to the tutorial's instructions, so I created the rustscript-learning directory in my cloned repository directory, ~/Downloads/tmp/RustScript directory.

I cdd into that directory, and created the hello.rjsc file, and then ran ../target/release/rjsc hello.rjsc, which resulted in the same problem I had when I was in my usual ~projects` directory -- the process seems to hang; it never completes. I gave it hours to do so (I went to bed, and checked on it the next morning).

Obviously I've done something wrong.

So I Ctrl-C'd that process, and then thought I'd try the WebAssembly version. I created the hello.html file in my current directory (~/Downloads/tmp/RustScript/rustscript-learning), and tried to start the Python web server (a "web server" I discovered a year or so ago, to my surprised pleasure, but suspected such a web server to be a quick-and-dirty kludge for when you don't want to go through the work of setting up a "real" web server like Apache2), and ran into another problem:

kent@westk-9463:~/Downloads/tmp/RustScript/rustscript-learning$ python3 ../serve.py [04:26:08] ✗ Directory 'www' not found. [04:26:08] Did you run build_wasm.bat first? kent@westk-9463:~/Downloads/tmp/RustScript/rustscript-learning

At this point, I could probably sort it out, but I'm finding that RustScript is not what I was expecting (a shell-scripting language), and I don't really have need for a web-scripting language (I'm not a web developer), and even though I was at first excited about a Rust-based scripting language (albeit from the perspective of thinking it was a shell-scripting language), which excitement carried me over into a desire to continue exploring it as a (not really needed by me) web-scripting language, the hurdles are higher than my desire to continue chasing a product I'm not sure really benefits me.

I only mention all of this so you'll have an idea of what neophytes might be facing when they come to check out RustScript.

I do really hope Rust makes progress in the web world; I like the general idea of Rust very much, and want to see it succeed, and think it would probably be a better tool than what I, in my limited experience, perceive about tools like JavaScript and php and Java and Kotlin and Go, etc.

[RustScript2025]

Thank you for this incredibly detailed feedback!

This is exactly the kind of insight we need from beginners trying RustScript for the first time. You've identified several critical issues that are blocking newcomers, and I really appreciate you taking the time to document your experience so thoroughly.

The Positioning Problem

You're absolutely right — the README needs to make it crystal clear right at the top that RustScript is a web-scripting language, not a shell-scripting language. It compiles to WebAssembly and runs in browsers, not on the command line like bash, Python, or PowerShell. I can completely understand the confusion, especially with a name like "RustScript." I'll update the opening paragraph immediately to set proper expectations.

The Hanging Compilation Bug 🚨

This is our highest priority issue to fix. When you ran ../target/release/rjsc hello.rjsc, it should have completed in seconds, not hung indefinitely. This is completely unacceptable and is blocking every beginner from even getting started. I need to reproduce this immediately and fix it before worrying about anything else in the documentation.

Can I ask a few quick questions to help debug this?

• What operating system are you running? (Looks like Linux from your prompt)
• Did you see any error messages at all, or did it just hang silently?
• What were the contents of your hello.rjsc file?

Edition 2024 Support

Good news: your Rust 1.91.1 definitely has Edition 2024 support (any version 1.85 or later does). I'll add a clear note about this in the prerequisites section so future users don't have the same worry.

The Missing www Directory

You're right that this is confusing. The serve.py script expects you to have run either build_wasm.bat (Windows) or build_wasm.sh (Linux/Mac) first to create the www directory. The tutorial should make this much more explicit as a required step, not something you discover when things fail.

Git and Path Confusion

Your instinct about where to clone the repository was fine — it doesn't really matter where you put it whilst you're learning. And your decision to copy rjsc to ~/bin made perfect sense, even if it turned out not to be necessary for the tutorial.

What I'm Going to Do

Based on your feedback, here are my immediate action items:

1. Fix the compilation hang bug — This is blocking everyone and must be resolved first
2. Rewrite the README opening — Make it immediately clear this is for web development, not shell scripting
3. Improve the tutorial flow — Add explicit steps for running the build scripts before attempting to serve
4. Add a "Common Issues" section — Including how to verify Edition 2024 support, what to do if compilation hangs, and clarification about the web-only focus
5. Test the complete beginner experience — I'll walk through the tutorial myself as if I know nothing and fix every stumbling block

Your Feedback Matters

I only mention all of this so you'll know that your detailed writeup has had a real impact. You represent exactly the kind of motivated beginner who could become an enthusiastic advocate for RustScript if the onboarding experience were smoother. Right now, the main barriers are unclear positioning and that compilation hang bug.

Even though RustScript might not be the tool you need right now (since you were looking for shell scripting), I genuinely hope you'll give it another try once we've fixed these issues. And if you do have any web development needs in the future, I'd love to hear how the improved experience works for you.

Would you be willing to test the improved documentation and fixed compiler once we've addressed the hanging bug? Your perspective as a "tinkerer but not a programmer" is incredibly valuable.

Thanks again for taking the time to document all of this so thoroughly!

[DebianFanatic]

On 11/29/25 4:30 AM, RustScript2025 wrote:

Thank you for this incredibly detailed feedback!
Thank you for your incredibly encouraging reply! Makes me want to be involved.

Can I ask a few quick questions to help debug this?

What operating system are you running? (Looks like Linux from your prompt)

/home/kent> cat /etc/debian_version
forky/sid
/home/kent>

Debian 13+

Did you see any error messages at all, or did it just hang silently?

Just hangs silently:

home/kent/Downloads/tmp/RustScript/rustscript-learning> ../target/release/rjsc hello_world.rjsc
^CError: nu::shell::terminated_by_signal

× External command was terminated by a signal
╭─[entry #7:1:1]
1 │ ../target/release/rjsc hello_world.rjsc
· ───────────┬──────────
· ╰── terminated by SIGINT (2)
╰────

/home/kent/Downloads/tmp/RustScript/rustscript-learning>

What were the contents of your hello.rjsc file?

/home/kent/Downloads/tmp/RustScript/rustscript-learning> cat hello.rjsc
fn main() {
console.log("Hello, World!");
}

main();

/home/kent/Downloads/tmp/RustScript/rustscript-learning>

Would you be willing to test the improved documentation and fixed compiler once we've addressed the hanging bug? Your perspective as a "tinkerer but not a programmer" is incredibly valuable.

Yes.

--

Kent

[DebianFanatic]

I remember seeing some warnings when I built RustScript, so I built it again to capture those warnings:

``
/home/kent/Downloads/tmp/RustScript> cargo build --release
warning: method determine_output_path is never used
--> src/main.rs:77:8
|
65 | impl Cli {
| -------- method in this implementation
...
77 | fn determine_output_path(&self) -> PathBuf {
| ^^^^^^^^^^^^^^^^^^^^^
|
= note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default

warning: associated items from_path, is_rustscript, and expected_output_extension are never used
--> src/ast.rs:435:12
|
434 | impl FileType {
| ------------- associated items in this implementation
435 | pub fn from_path(path: &PathBuf) -> Self {
| ^^^^^^^^^
...
446 | pub fn is_rustscript(&self) -> bool {
| ^^^^^^^^^^^^^
...
450 | pub fn expected_output_extension(&self, target: &str) -> &'static str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^

warning: struct DialectRule is never constructed
--> src/ast.rs:464:12
|
464 | pub struct DialectRule {
| ^^^^^^^^^^^

warning: associated functions union and intersection are never used
--> src/ast.rs:473:12
|
471 | impl Type {
| --------- associated functions in this implementation
472 | /// Creates a union type (TypeScript-style: A | B | C).
473 | pub fn union(types: Vec) -> Self {
| ^^^^^
...
482 | pub fn intersection(types: Vec) -> Self {
| ^^^^^^^^^^^^

warning: enum Token is never used
--> src/lexer.rs:19:10
|
19 | pub enum Token {
| ^^^^^

warning: struct Lexer is never constructed
--> src/lexer.rs:168:12
|
168 | pub struct Lexer<'input> {
| ^^^^^

warning: associated function new is never used
--> src/lexer.rs:176:12
|
172 | impl<'input> Lexer<'input> {
| -------------------------- associated function in this implementation
...
176 | pub fn new(input: &'input str) -> Self {
| ^^^

warning: variants Mismatch and CannotInfer are never constructed
--> src/typechecker.rs:19:5
|
16 | pub enum TypeError {
| --------- variants in this enum
...
19 | Mismatch { expected: Type, found: Type, span: Span },
| ^^^^^^^^
...
23 | CannotInfer { span: Span },
| ^^^^^^^^^^^
|
= note: TypeError has derived impls for the traits Clone and Debug, but these are intentionally ignored during dead code analysis

warning: variant Borrowed is never constructed
--> src/borrow_checker.rs:28:5
|
22 | pub enum OwnershipState {
| -------------- variant in this enum
...
28 | Borrowed(Vec),
| ^^^^^^^^
|
= note: OwnershipState has derived impls for the traits Clone and Debug, but these are intentionally ignored during dead code analysis

warning: fields files and file_ids are never read
--> src/diagnostics.rs:27:5
|
25 | pub struct DiagnosticManager {
| ----------------- fields in this struct
26 | /// Storage for source files and their contents.
27 | files: SimpleFiles<String, String>,
| ^^^^^
28 | /// List of file IDs that have been added.
29 | file_ids: Vec,
| ^^^^^^^^

warning: methods add_file and report_error are never used
--> src/diagnostics.rs:43:12
|
32 | impl DiagnosticManager {
| ---------------------- methods in this implementation
...
43 | pub fn add_file(&mut self, name: String, source: String) -> usize {
| ^^^^^^^^
...
64 | pub fn report_error(&self, span: Span, message: &str) -> String {
| ^^^^^^^^^^^^

warning: struct SourceMap is never constructed
--> src/sourcemap.rs:18:12
|
18 | pub struct SourceMap {
| ^^^^^^^^^

warning: struct SourceMapGenerator is never constructed
--> src/sourcemap.rs:41:12
|
41 | pub struct SourceMapGenerator {
| ^^^^^^^^^^^^^^^^^^

warning: struct Mapping is never constructed
--> src/sourcemap.rs:51:8
|
51 | struct Mapping {
| ^^^^^^^

warning: associated items new, add_source, add_mapping, generate, encode_vlq, and base64_char are never used
--> src/sourcemap.rs:67:12
|
66 | impl SourceMapGenerator {
| ----------------------- associated items in this implementation
67 | pub fn new(file: String) -> Self {
| ^^^
...
75 | pub fn add_source(&mut self, source_path: String) -> u32 {
| ^^^^^^^^^^
...
80 | pub fn add_mapping(
| ^^^^^^^^^^^
...
102 | pub fn generate(&self) -> SourceMap {
| ^^^^^^^^
...
157 | fn encode_vlq(&self, output: &mut String, value: i32) {
| ^^^^^^^^^^
...
177 | fn base64_char(&self, value: i32) -> char {
| ^^^^^^^^^^^

warning: struct StdLib is never constructed
--> src/std_lib.rs:20:12
|
20 | pub struct StdLib {
| ^^^^^^

warning: associated function new is never used
--> src/std_lib.rs:33:12
|
25 | impl StdLib {
| ----------- associated function in this implementation
...
33 | pub fn new() -> Self {
| ^^^

warning: rustscript (bin "rjsc") generated 17 warnings
Finished release profile [optimized] target(s) in 0.64s
/home/kent/Downloads/tmp/RustScript>

[RustScript2025]

It's going to take a few days, I'm only one person & this week I have a bunch of things to do, so I'll start as soon as I can.

[RustScript2025]

Hi Kent,

Thanks for the detailed bug report! I've been able to reproduce and identify the issue.

The Problem:

When you run rjsc hello.rjsc, the compiler is actually searching for and attempting to compile every .rjsc file in your entire directory tree, not just the one you specified. It uses a recursive glob pattern (**/*.rjsc) that walks through all subdirectories from the project root.

Here's what's happening:

You run ../target/release/rjsc hello.rjsc from your rustscript-learning directory
The compiler determines the "project root" by taking the parent directory of your input file (which is your current directory)
It then recursively searches that entire tree for all .rjsc files
On Linux, this recursive search can hang or take an extremely long time, especially if there are symlinks, large subdirectories (like .git), or permission issues
On Windows, the same glob pattern completes quickly due to different filesystem characteristics, which is why I didn't catch this during development.

The Fix:

The compiler should only compile the specific file you provide, not scan the entire directory tree. I'm working on a fix that will:

Compile only the specified file when you provide a file path
Only do the recursive search when you explicitly provide a directory path
This should resolve the hanging issue you're experiencing. I'll have a fix pushed shortly and would appreciate it if you could test it once it's available.

Thanks again for your patience and for providing such thorough feedback!

[DebianFanatic]

I just re-cloned the repository;

# On Linux/Mac ./build_wasm.sh

Just FYI; build_wasm.sh is not executable, and needs a chmod +x build_wasm.sh first.

Running the script was then successful, and I was able to start the python web server and open the games demo page.

=====

You have a "Compiler hangs and never finishes?" section in the "Troubleshooting" section under the "Browser Runtime" heading, but up to this point there's been no mention of compiling to hello.rjsc, so this information here can be confusing to a newbie.

This information is also duplicated farther down in the README, after the "Learning RustScript"/"Complete Tutorial" is mentioned; it makes much better sense here, but it would probably make even more sense in the "Complete Tutorial".

Nice rewrite of the README, though; excellent job!

[RustScript2025]

I can’t actually set executable permissions — like using chmod +x — through GitHub’s web interface or any of its APIs. GitHub doesn’t handle permissions that way, since those flags are tied to your own file system rather than the file’s contents. The only way to make a script executable is to set the permissions locally on your machine.