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 :

Put @microblog.desipenguin.com@web.brid.gy in the search box.

Thanks to Bridgy.fed this site automatically gets it’s own mastodon account.

Following this account is like subscribing to the RSS feed (I think 😄)

Few days ago, I heard about this on some podcast (maybe changelog ? 🤷‍♂)

I have been using similar notation for my commits - even for this blog¹ - but I did not know it is a specification.

The idea is that very first word of the commit message should indicate what sort of commit is it.

Most common ones are : fix, feat (To indicate bugfix and a feature)

Other useful ones are: docs, style, refactor, test

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

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”. But there is a way to access both the new and old variables. But in that case we have to explicit.

(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.
  • By default, it is split 50-50
  • Usually, you’ll want more screen real estate for the editor (Helix in my case, but works for (n)vi(m) or emacs-in-terminal as wlel)

There is also a possibility of running a floating pane. This may be used for running a server process, which mostly one doesn’t need to look at constantly.

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

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!(r#"{{contents: {}}}"#, var1);
    println!("{}", formatted);
}

This gives output as : {contents: test1}