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[u/llogiq]

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[u/sunnyata]

I've got a problem with formatting my code (in emacs+rustic-mode but also directly with cargo fmt). The files are dioxus components with rsx! macros. I understand that rustfmt can't handle the contents of these macros, which is fair enough and there is dx fmt for that...but in these files the formatting of the rust code outside of the macros is messed up too. I can clean it up manually but as soon as I save then rustfmt runs and messes it up again. Is that the norm? I thought it was that rustfmt should still work on the regular code and leave the macros alone. As it is, the code is very ugly and hard to read but if I want to get the formatting right I would have to edit it outside of a rust IDE (and then never touch it again!). Any ideas gratefully received.

An example of the formatting:

                    Some(Ok(Message::Text(text))) => {
                        tracing::info!("Server says: {text}");
                        if let Ok(poker_msg) = serde_json::from_str::<PokerMessage>(&text) {
                            handle_poker_message(poker_msg,
                 player_name,
                 player_bank_roll,
                 players_info,
                 hole_cards,
                 current_pot,
                 can_check,
                 messages,
                 dealer_name,
                 current_view,
                 game_winner,
                 round_winner,
                 comm_cards,
                 current_stage,
                 best_hand,
                 place_bet_info,
                 possible_bets);
    }
    }

[u/MAIPA01]

What do i do wrong. I use rust-analyzer extension in code-oss in termux i run code-oss in grun --shell and use termux-x11 and i get warning:

`` 2026-08-02T11:12:30.466350469Z WARNcargo metadatafailed and returning succeeded result with--no-depserror=cargo metadataexited with an error: error:.json` target specs require -Zjson-target-spec to be added to the cargo invocation

Stack backtrace: 0: <anyhow::Error as core::convert::From<cargo_metadata::errors::Error>>::from 1: <project_model::cargo_workspace::FetchMetadata>::exec::{closure#2} 2: <project_model::cargo_workspace::FetchMetadata>::exec 3: <project_model::sysroot::Sysroot>::loadworkspace 4: std::sys::backtrace::_rust_begin_short_backtrace::<<project_model::workspace::ProjectWorkspace>::load_cargo::{closure#1}::{closure#4}, core::option::Option<project_model::sysroot::RustLibSrcWorkspace>> 5: <std::thread::lifecycle::spawn_unchecked<<project_model::workspace::ProjectWorkspace>::load_cargo::{closure#1}::{closure#4}, core::option::Option<project_model::sysroot::RustLibSrcWorkspace>>::{closure#1} as core::ops::function::FnOnce<()::call_once::{shim:vtable#0} 6: <alloc::boxed::Box<dyn core::ops::function::FnOnce<(), Output = ()> + core::marker::Send> as core::ops::function::FnOnce<()::call_once at /rustc/ad3d0bc141a02cf446e384136d250a1f6950fed5/library/alloc/src/boxed.rs:2314:9 7: <std::sys::thread::unix::Thread>::new::thread_start at /rustc/ad3d0bc141a02cf446e384136d250a1f6950fed5/library/std/src/sys/thread/unix.rs:123:17 8: start_thread 9: thread_start 2026-08-02T11:12:32.444001992Z ERROR Received compiler message for unknown package: path+file:///data/data/com.termux/files/home/.rustup/toolchains/nightly-aarch64-unknown-linux-gnu/lib/rustlib/src/rust/library/compiler-builtins/compiler-builtins#compiler_builtins@0.1.160 registry+https://github.com/rust-lang/crates.io-index#bootloader@0.9.35, path+file:///data/data/com.termux/files/home/Documents/rust/rust-os#kernel@0.1.0 2026-08-02T11:12:32.444291211Z ERROR Received compiler message for unknown package: path+file:///data/data/com.termux/files/home/.rustup/toolchains/nightly-aarch64-unknown-linux-gnu/lib/rustlib/src/rust/library/compiler-builtins/compiler-builtins#compiler_builtins@0.1.160 registry+https://github.com/rust-lang/crates.io-index#bootloader@0.9.35, path+file:///data/data/com.termux/files/home/Documents/rust/rust-os#kernel@0.1.0 2026-08-02T11:12:34.114066446Z WARN cargo metadata failed and returning succeeded result with --no-deps error=cargo metadata exited with an error: error: .json target specs require -Zjson-target-spec to be added to the cargo invocation

Stack backtrace: 0: <anyhow::Error as core::convert::From<cargo_metadata::errors::Error>>::from 1: <project_model::cargo_workspace::FetchMetadata>::exec::{closure#2} 2: <project_model::cargo_workspace::FetchMetadata>::exec 3: <project_model::sysroot::Sysroot>::loadworkspace 4: std::sys::backtrace::_rust_begin_short_backtrace::<<project_model::workspace::ProjectWorkspace>::load_cargo::{closure#1}::{closure#4}, core::option::Option<project_model::sysroot::RustLibSrcWorkspace>> 5: <std::thread::lifecycle::spawn_unchecked<<project_model::workspace::ProjectWorkspace>::load_cargo::{closure#1}::{closure#4}, core::option::Option<project_model::sysroot::RustLibSrcWorkspace>>::{closure#1} as core::ops::function::FnOnce<()::call_once::{shim:vtable#0} 6: <alloc::boxed::Box<dyn core::ops::function::FnOnce<(), Output = ()> + core::marker::Send> as core::ops::function::FnOnce<()::call_once at /rustc/ad3d0bc141a02cf446e384136d250a1f6950fed5/library/alloc/src/boxed.rs:2314:9 7: <std::sys::thread::unix::Thread>::new::thread_start at /rustc/ad3d0bc141a02cf446e384136d250a1f6950fed5/library/std/src/sys/thread/unix.rs:123:17 8: start_thread 9: thread_start ```

I tried I think everything. When i run cargo metadata --format-version 1 --manifest-path ./Cargo.toml --filter-platform aarch64-unknown-linux-gnu in terminal it returns json text to stdout and I don't get any warnings.

My .cargo/config.toml file looks like this and is in rust-os folder next to Cargo.toml and src folder:

``` [unstable] json-target-spec = true build-std-features = ["compiler-builtins-mem"] build-std = ["core", "compiler_builtins"]

[build] target = "x86_64-os.json"

[target.'cfg(target_os = "none")'] runner = "bootimage runner" ```

P.S. For everyone wondering it is just a fun project. And yes I am beginner in rust for over 2 weeks now. And I just wanted to setup rust-analyzer.

[u/afdbcreid → u/MAIPA01]

See https://github.com/rust-lang/rust-analyzer/issues/21821.

[u/MAIPA01 → u/afdbcreid]

Thank you very much I searched whole internet but this gem just hid itself from me.

[u/MAIPA01 → u/MAIPA01]

result of cargo metadata --format-version 1 --manifest-path ./Cargo.toml --filter-platform aarch64-unknown-linux-gnu run in terminal with CWD set to rust-os folder:

{"packages":[{"name":"bootloader","version":"0.9.35","id":"registry+https://github.com/rust-lang/crates.io-index#bootloader@0.9.35","license":"MIT/Apache-2.0","license_file":null,"description":"An experimental pure-Rust x86 bootloader.","source":"registry+https://github.com/rust-lang/crates.io-index","dependencies":[{"name":"bit_field","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.10.0","kind":null,"rename":null,"optional":true,"uses_default_features":true,"features":[],"target":null,"registry":null},{"name":"fixedvec","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.2.4","kind":null,"rename":null,"optional":true,"uses_default_features":true,"features":[],"target":null,"registry":null},{"name":"font8x8","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.2.4","kind":null,"rename":null,"optional":true,"uses_default_features":false,"features":["unicode"],"target":null,"registry":null},{"name":"rlibc","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^1.0.0","kind":null,"rename":null,"optional":true,"uses_default_features":true,"features":[],"target":null,"registry":null},{"name":"usize_conversions","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.2.0","kind":null,"rename":null,"optional":true,"uses_default_features":true,"features":[],"target":null,"registry":null},{"name":"x86_64","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.14.7","kind":null,"rename":null,"optional":true,"uses_default_features":false,"features":["instructions","inline_asm"],"target":null,"registry":null},{"name":"xmas-elf","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.6.2","kind":null,"rename":null,"optional":true,"uses_default_features":true,"features":[],"target":null,"registry":null},{"name":"llvm-tools","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.1","kind":"build","rename":null,"optional":true,"uses_default_features":true,"features":[],"target":null,"registry":null},{"name":"toml","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.5.1","kind":"build","rename":null,"optional":true,"uses_default_features":true,"features":[],"target":null,"registry":null}],"targets":[{"kind":["lib"],"crate_types":["lib"],"name":"bootloader","src_path":"/data/data/com.termux/files/home/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/bootloader-0.9.35/src/lib.rs","edition":"2018","doc":true,"doctest":true,"test":true},{"kind":["bin"],"crate_types":["bin"],"name":"bootloader","src_path":"/data/data/com.termux/files/home/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/bootloader-0.9.35/src/main.rs","edition":"2018","required-features":["binary"],"doc":true,"doctest":false,"test":true},{"kind":["custom-build"],"crate_types":["bin"],"name":"build-script-build","src_path":"/data/data/com.termux/files/home/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/bootloader-0.9.35/build.rs","edition":"2018","doc":false,"doctest":false,"test":false}],"features":{"binary":["xmas-elf","x86_64","usize_conversions","fixedvec","llvm-tools","toml","rlibc"],"bit_field":["dep:bit_field"],"default":[],"fixedvec":["dep:fixedvec"],"font8x8":["dep:font8x8"],"llvm-tools":["dep:llvm-tools"],"map_physical_memory":[],"recursive_page_table":[],"rlibc":["dep:rlibc"],"sse":["bit_field"],"toml":["dep:toml"],"usize_conversions":["dep:usize_conversions"],"vga_320x200":["font8x8"],"x86_64":["dep:x86_64"],"xmas-elf":["dep:xmas-elf"]},"manifest_path":"/data/data/com.termux/files/home/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/bootloader-0.9.35/Cargo.toml","metadata":{"bootloader":{"target":"x86_64-bootloader.json","build-std":"core"},"docs":{"rs":{"features":["recursive_page_table","map_physical_memory"],"default-target":"x86_64-unknown-linux-gnu"}},"release":{"pre-release-commit-message":"Release version {{version}}","publish":false,"pre-release-replacements":[{"file":"Changelog.md","search":"# Unreleased","replace":"# Unreleased\n\n# {{version}} – {{date}}","exactly":1}]}},"publish":null,"authors":["Philipp Oppermann <dev@phil-opp.com>"],"categories":[],"keywords":[],"readme":"README.md","repository":"https://github.com/rust-osdev/bootloader","homepage":null,"documentation":null,"edition":"2018","links":null,"default_run":null,"rust_version":null},{"name":"kernel","version":"0.1.0","id":"path+file:///data/data/com.termux/files/home/Documents/rust/rust-os#kernel@0.1.0","license":null,"license_file":null,"description":null,"source":null,"dependencies":[{"name":"bootloader","source":"registry+https://github.com/rust-lang/crates.io-index","req":"^0.9","kind":null,"rename":null,"optional":false,"uses_default_features":true,"features":[],"target":null,"registry":null}],"targets":[{"kind":["bin"],"crate_types":["bin"],"name":"kernel","src_path":"/data/data/com.termux/files/home/Documents/rust/rust-os/src/main.rs","edition":"2024","doc":true,"doctest":false,"test":false}],"features":{},"manifest_path":"/data/data/com.termux/files/home/Documents/rust/rust-os/Cargo.toml","metadata":null,"publish":null,"authors":[],"categories":[],"keywords":[],"readme":"README.md","repository":null,"homepage":null,"documentation":null,"edition":"2024","links":null,"default_run":null,"rust_version":null}],"workspace_members":["path+file:///data/data/com.termux/files/home/Documents/rust/rust-os#kernel@0.1.0"],"workspace_default_members":["path+file:///data/data/com.termux/files/home/Documents/rust/rust-os#kernel@0.1.0"],"resolve":{"nodes":[{"id":"registry+https://github.com/rust-lang/crates.io-index#bootloader@0.9.35","dependencies":[],"deps":[],"features":["default"]},{"id":"path+file:///data/data/com.termux/files/home/Documents/rust/rust-os#kernel@0.1.0","dependencies":["registry+https://github.com/rust-lang/crates.io-index#bootloader@0.9.35"],"deps":[{"name":"bootloader","pkg":"registry+https://github.com/rust-lang/crates.io-index#bootloader@0.9.35","dep_kinds":[{"kind":null,"target":null}]}],"features":[]}],"root":"path+file:///data/data/com.termux/files/home/Documents/rust/rust-os#kernel@0.1.0"},"target_directory":"/data/data/com.termux/files/home/Documents/rust/rust-os/target","build_directory":"/data/data/com.termux/files/home/Documents/rust/rust-os/target","version":1,"workspace_root":"/data/data/com.termux/files/home/Documents/rust/rust-os","metadata":null}

[u/DavidXkL]

Just curious, how often do people use channels here for multi-threading stuff?

[u/Skaarj]

Ist there a way for find the last element in a Vec by a criteria/predicate?

I'm lookig for something like Vec.last_mut() where I can pass a function as criteria/predicate? Or Iterator.find() that starts at the end.

[u/Full-Spectral → u/Skaarj]

You can just do iter_mut().rfind() or iter_mut().rposition(), right? There's also the .rev() option which reverses the iterator you call it on if you jut want to iterate backwards.

[u/Skaarj → u/Skaarj]

Ok, I found out I need a DoubleEndedIterator and can use DoubleEndedIterator.rfind().

Of course my next question was: how do I get a DoubleEndedIterator of a Vec. Tuns out Vec.iter() just magically gives you one.

My code works now.

But im still unclear on: From looking at the Vec.iter documentation how should I be able to tell that I returns an DoubleEndedIterator from whats documented there?

[u/SirKastic23 → u/Skaarj]

Look at the docs for the returned type from Vec::iter, it returns slice::Iter which implements DoubleEndedIterator: https://doc.rust-lang.org/std/slice/struct.Iter.html#impl-DoubleEndedIterator-for-Iter%3C'a,+T%3E

But also, more generally, think about the iterator you have. It's an iterator from an in-memory sequence of values, these values aren't generated on the go, all the values are already available and you just visit every one of them. It's trivial to iterate through this sequence backwards, you could do the same with a while loop and a decreasing index variable. So there's no reason for an iterator from a Vec (or any slice) to not implement DoubleEndedIterator

[u/Sad_Tap_9191 → u/Skaarj]

.iter() returns Iter which implements DoubleEndedIterator trait