Overview

fn main() {
    let random_number = generate_random_number();
    let mut my_choice = 10;
    my_choice += random_number;
    println!("{my_choice}");
}

fn generate_random_number() -> i32 {
    4 // chosen by dice roll, guaranteed to be random
}

What is Rust?

Rust is an empathic systems programming language that is determined to not let you shoot yourself in the foot.

A Little Bit of History

  • Rust began around 2006
  • An experimental project by Graydon Hoare
  • Adopted by Mozilla
  • Presented to the general public as version 0.4 in 2012
  • Looked a bit Go-like back then

Focus

  • Rust lost many features leading up to 1.0:
    • Garbage collector
    • evented runtime
    • complex error handling
    • ~T syntax
  • Orientation towards a usable systems programming language

Development

  • Always together with a larger project (e.g. Servo)
  • Early adoption of regular releases, deprecations and an RFC process

Release Method

  • Nightly releases
  • experimental features are only present on nightly releases
  • Every 6 weeks, the current nightly is promoted to beta
  • After 6 weeks of testing, beta becomes stable
  • Guaranteed backwards-compatibility
  • Makes small iterations easier

Note:

  • Cargo's "stabilization" section https://doc.crates.io/contrib/process/unstable.html#stabilization
  • Crater tool
  • Editions

Goals

  • Explicit over implicit
  • Predictable runtime behaviour
  • Supporting stable software development for programming at large
  • Pragmatism and easy integration
  • Approachable project

Many examples in this course are very small, which is why we will also spend time discussing the impact of many features on large projects.

The Three Words

  • Safety
  • Performance
  • Productivity

Safety

  • Rust is memory-safe and thread-safe
    • Buffer overflows, use-after-free, double free: all impossible
    • Unless you tell the compiler you know what you're doing
  • De-allocation is automated
    • Great for files, mutexes, sockets, etc

Performance

  • These properties are guaranteed at compile time and have no runtime cost!
  • Optimizing compiler based on LLVM
  • Features with runtime cost are explicit and hard to activate "by accident"
  • Zero-cost abstractions
  • Use threads with confidence

Productive

  • User-focused tooling
  • Comes with a build-system, dependency manager, formatter, etc
  • Compiler gives helpful error messages
  • FFI support to interface with existing systems

Where do Rustaceans come from?

From diverse backgrounds:

  • Dynamic languages (JS, Rubyists and Pythonistas)
  • Functional languages like Haskell and Scala
  • C/C++
  • Safety critical systems