Conditional Compilation in Rust

Today I learnt that certain rust code can be marked such that it is compiled only for specific platform. This makes sense for low level libraries that provide platform-specific functionality that is not available on other platforms. This is achieved by tagging the function with #[cfg(target_os = "xyz")] Here xyz can be one of the following : “windows” “macos” “ios” “linux” “android” “freebsd” “dragonfly” “openbsd” “netbsd” Similar to target_os, here are other options :

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rust can Divide by Zero

At least for floating point numbers, it does not crash/panic! 🤷‍♂ fn main() { let x = 10.0; let y = 0.0; println!("{:?}", x/y); } This above code returns inf But if we change the number to int, compiler catches this 1 at shows the following error: error: this operation will panic at runtime This is a contrived example. Instead of static values, if these were passed at runtime, it would (should?

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Rust: Clone vs Copy

One of the strength of Rust is memory management. This also leads to compiler errors related to move or borrow When we assign an existing variable to new variable, two things can happen. Either the data is copied - in that case we can use both old and the new variable without worry. 1 Or data is moved - now we can only use the new variable, as the old variable is “out of scope”.

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How to create IDE like experience in terminal using Zellij

(undocumented?) Zellij Keybindings Undocumented, because these don’t show up in the default configuration, which shows (I assume) most useful key bindings. I had to look for these, and found them in Github discussions/issues. Ctrl p d Ctrl p is for pane, but d after that (which I assume stands for down) is not documented. This creates a new terminal in horizontal split fashion 1 Ctrl n - to reduce the size of the terminal.

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error: Unknown binary 'rust-analyzer'

As I am setting up my new machine, I came across this error when emacs tried to use rust-analyzer error: Unknown binary 'rust-analyzer' in official toolchain 'stable-x86_64-apple-darwin'. As mentioned in this SO question, which rust-analyzer did not show any error.1 Luckily, the same SO question also had the solution I needed to explicitly install it via rustup component add rust-analyzer Luckily, the comment in the accepted answer also explained why which works.

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Format raw strings in rust

When refactoring code to make API call to Gemini, I learnt how to format raw strings in rust. fn main() { let var1 = "test1"; let formatted = format!(r#"var1 is: {}"#, var1); println!("{}", formatted); } This gives output as : var1 is: test1 If you want { in the output, then it needs to be escaped with additional { like: fn main() { let var1 = "test1"; let formatted = format!

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How to use .env files with your rust project

It is very important that secrets are stored in environment variables during the runtime. During the development, it makes sense to use .env file. In my last project, there were probably 40+ variables in the .env. Although that project was in RoR the idea of .env itself is not new. But for me, using .env with rust is new. For my current (self) assignment, I needed to store an API Key.

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Why I switched to Zellij

I had tried switching to tmux for local shell sessions in past, but never truly understood why I might need it. I extensively used tmux for remote sessions. But why might I need it locally ? Then slowly I stopped using tmux and switched to wezterm which provided multiple tabs. Fast-forward several years later. Recently I came across Zellij. I decided to give it a go. When I had tried tmux it took some time to get used to the keybinding.

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How I generated 2000 parallel requests using nu-shell

At work, I need to load test new framework I had deployed. Usually, I work with QA team. They use JMeter (with Azure Load test) for such task. But today, the QA person was busy with other tasks, and I didn’t want to get blocked. Since I am learning rust, (nu-shell is built in rust) I remembered that it may be possible to run parallel requests in nu-shell. and it is!

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Clippy

Clippy is a linter for Rust programming language. If you are annoyed by the compiler (shouting at telling you how your code is wrong), wait till you install and use clippy 😄 Jokes apart, why I want to use clippy is it tells us about idiomatic rust and can autofix issues (if we tell it to do so) Couple of fun facts I discovered : First search result for clippy is not what I was looking for 😄 till I searched for rust clippy clippy can not be installed via cargo install (As I tried initially) (As with rest of the rust ecosystem) there was a helpful error message with solution 😇 error: Clippy is no longer available via crates.

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