Joke tool that allows you to write and compile Rust code as folder names. The syntax for every folder name is <line number> <code> (for example "11 let a = 1;"). See lines 46-55 for the other syntax rules. Crate name is supposed to be "folderustc". Usage: folderustc <source folder> <rust compiler args>.

main.rs

use std::{
    fs::{self, DirEntry, File},
    io::{prelude::*, Error, Result},
    process::Command
};

//Default temp file name
const FILE_NAME: &'static str = "source.rs";

fn main() -> Result<()> {
    //Gets args and skips the first one (executable name)
    let mut args = std::env::args().skip(1);
    //Gets the source folder from remaining args
    let code_folder = args
        .next()
        .expect("Please specify a source directory!");

    //Reads the source code
    let source_code = fs::read_dir(&code_folder)
        .expect("Invalid source directory!")
        .fold(String::new(), process_folder_name);
    
    //Temp file path
    let temp_path: String = String::from(FILE_NAME);
    //Creates the file and write the source code
    let mut file = File::create(&temp_path).unwrap();
    file.write_all(source_code.as_bytes())?;
    //Compiles
    Command::new("rustc")
        .arg(FILE_NAME)
        .args(args)
        .output()
        .expect("Compilation failed!");

    //Removes temp file and returns
    fs::remove_file(&temp_path)?;
    Ok(())
}

//Gets called for each subfolder corresponding to a line
fn process_folder_name(data: String, current: std::result::Result<DirEntry, Error>) -> String {
    let fname = current.unwrap().file_name();
    let raw = fname.to_str().expect("IO Error!");

    //some replaces are applied here because folder names do not support some characters
    data + "\n" + &raw[(raw.find(" ").unwrap_or(0) + 1)..]
        .replace("''", "\"") //use '' as double quotes
        .replace("@", "*") //use @ as raw pointer thing
        .replace("§", "?") //use § as question mark
        .replace("°-", ">") //use °- as greater than
        .replace("-°", "<") //use -° as less than
        .replace("-°°", "\\") //use -°° as left bar
        .replace("°°-", "/") //use °°- as right bar
        .replace("-°-", "|") //use -°- as middle bar
        .replace("^^", ":") //use ^^ as colon
}

uwu this is so cursed