Rust cheat sheet (2022)

Sat, 11 Dec 2021 22:21:47 +1100

Please refer to Don Bright’s original rust-lang-cheat-sheet which I based much of this content off, as I work through The Book.

Rust in a nutshell

Syntax similar to C
Ownership of memory enforced at compile time
Statically linked
Functional-ish, generic-ish, not so objecty
Control flow using patterns, match keyword
Packages: ‘cargo’ command, https://crates.io
Testing: cargo test, #[test]
Concurrency: ownership, mutability, channels, mutex, crossbeam + Rayon packages
Auto formatter: rustfmt filename.rs
Compiler engine: LLVM
Raw pointers, low level: unsafe{} keyword

Documentation

rustup doc for offline docs!
doc.rust-lang.org standard library, primitive types, standard macros
docs.rs for package documentation

Toolchain

$ rustup.sh               # install rust, see rust-lang.org for details
$ cargo new myproj        # start new executable project
$ cargo new --bin myproj  # as above
$ cargo new --lib myproj  # start new library project
$ cd myproj               # cd into the new directory
$ ls -lR                  # list our skeleton of files
src/main.rs               # main.rs, has main() entry point
Cargo.toml                # Cargo.toml defines packaging
$ $EDITOR Cargo.toml      # add dependencies and other details
$ cargo build             # downloads dependencies + builds main.rs
$ cargo build --release   # release build
$ cargo check             # make sure code compiles, without binary outputs
$ cargo update            # ignore Cargo.lock and figure out latest versions
$ cargo run               # runs program created from main.rs
$ cargo doc --open        # local web based doc
$ cargo test              # runs tests (in parallel by default)
$ cargo test -- --test-threads=1  # run tests one at a time
$ cargo test -- --nocapture       # run tests, show output
$ cargo run --example fundemo -- --argtodemo # run example with argument
$ rustc --explain E0384   # eli5 what an error code means

Mutability basic

let x = false;           // all variable bindings are immutable by default
x = true;                // compile error: can't change an immutable binding
let mut p = false;       // "mut" designates a binding as mutable
p = true;                // ok, mutable binding can change;

Types and variables

Rust provide two compound types; arrays and tuples.

Rust on Benny Simmonds

Rust cheat sheet (2022)

Rust in a nutshell

Documentation

Toolchain

Mutability basic

Types and variables