Rust (programming language)

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Rust is a low-level programming language. It's main advantage is supposed to be memory safety by default.
Recently, Rust has been adopted to many systems applications such as the Linux kernel drivers and Android.

Usage

Installation

See Install

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

Syntax

Basics

// Const variable, must have type annotation.
const IMPORTANT_VALUE: i32 = 50;
fn main() {
  // C++: int x = 3;
  let mut x: i32 = 3;

  // Shadowing, creating a new variable.
  let x = x + 5;

  // Loop over values [0, 1, 2]
  for i in 0..3 {
    println!("This number is {}", i);
  }

  // Ternary is a single line if statement.
  let big_x = if x > 5 {x} else {5};
}

fn lerp(a: f64, b: f64, x: f64) -> f64 {
   // No semicolon implies return.
  (1.0 - x) * a + x * b
}

// Copied from rustlings.
pub fn fizz_if_foo(fizzish: &str) -> &str {
    if fizzish == "fizz" {
        "foo"
    } else if fizzish == "fuzz" {
        "bar"
    } else {
        "baz"
    }
}

Borrowing

This is like references in C++.

let x = 5;
let mut y = 6;

// C++: const int &
example_borrow(&x)
// C++: int&
example_mut_borrow(&mut y)

Resources