Rust

Rust started around Mozilla and is now a separate project. There is no garbage collector. Instead there is an ownership rule: every value has one owner. If the rule breaks, the program does not build. That stops many mistakes before the program runs.

Rust shows up in a command-line tool, a network service, a browser piece, and a Wasm module.

• A safer system tool
• A fast API
• Calling an existing C library
• Work in the browser with Wasm

With Rust you write a tool and a service with less risk of a memory overrun. cargo builds the package and runs tests. The learning curve is steep, so Python stays shorter for a small script.

The first week is hard. When the borrow checker rejects code, the reason is a memory rule, not the syntax. After that, a refactor is calmer because many mistakes do not build.

Advantage: speed and memory safety sit together. Limit: the compiler is strict, build time can grow, and a GUI or a simple website is still not the first choice.

Ownership is who owns a value. A borrow is a temporary look. String is growable text. &str is a view of text that lives somewhere else.

• cargo new opens a project
• A crate is a package
• Result returns an error as a value
• An unsafe block loosens the rule on purpose

This program writes one line to the terminal. The command is cargo run.

fn main() {
    println!("Hello");
}

• Has Rust replaced C++? Not everywhere. It is often chosen for a new system tool. Old code stays.
• Is there a garbage collector? No. Memory is tracked by the ownership rule.
• Is it as fast to learn as Python? No. The first week is steeper.