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Weird Expressions in Rust

wakunguma.com

1–10 of 155 posts

Re: Weird Expressions in Rust

#3
Great, now this stuff gets fed into LLM trainings and we'll see them in the next-gen model outputs.

Seriously though, I love "abusing" programming languages in unexpected ways. My favorite so far is: https://evuez.net/posts/cursed-elixir.html. Reading this made me realize Elixir is literally macros all the way down, and it's a Lisp!

Re: Weird Expressions in Rust

#5
they exist because whole language built to treat expressions as firstclass citizens : blocks, ifs, matches, even macros as expressions that return values. so once you internalize that, all these weirdo one liners are artifacts. just artifact of a system where expressions compose infinitely. the syntax tree runs deeper than most people's habbits allow. you hit that depth and brain says this is wrong but compiler's allowing.

Re: Weird Expressions in Rust

#6
This post is missing my favorite one!

    fn evil_lincoln() { let _evil = println!("lincoln"); }
What's weird about this?

To understand what evil_lincoln is doing, you have to understand very old Rust. Here's the commit that introduced it: https://github.com/rust-lang/rust/commit/664b0ad3fcead4fe4d2...

    fn evil_lincoln() {
        let evil 
log was a keyword to print stuff to the screen. Hence the joke, https://en.wikipedia.org/wiki/Lincoln_Logs Now that log is the println! macro, the joke is lost.

It doesn't say explicitly why this is "weird", but given some other comments in the file,

    // FIXME: Doesn't compile
    //let _x = log true == (ret 0);
I am assuming that using the return value of log was buggy, and so this tested that you could save it in a variable. I don't remember the exact semantics of log, but if it's like println!, it returns (), which is useless, so binding it to a variable is something you'd never write in real code, so it's "weird" in that sense.

Re: Weird Expressions in Rust

#10

This post is missing my favorite one! fn evil_lincoln() { let _evil = println!("lincoln"); } What's weird about this? To understand what evil_lincoln is doing, you have to understand very old Rust. Here's the commit that introduced it: https://github.com/rust-lang/rust/commit/664b0ad3fcead4fe4d2... fn evil_lincoln() { let evil log was a keyword to print stuff to the screen. Hence the joke, https://en.wikipedia.org/wi…

What's the joke exactly? English is not my native language.
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