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rust

Table of Contents

Tooling
#

Install Rust with the official installation script.

  • rustc: The Rust compiler
  • rustup: Manages Rust versions/updates
  • cargo: Rust’s build tool

Running and building
#

Cargo is the primary tool development with Rust.

New project
#

cargo new --bin NAME # create a application
cargo new --bin NAME # create a library

Directory structure:

.
├── Cargo.toml
└── src
    └── main.rs

Cargo.toml contains project meta info and dependencies.

Run project
#

cargo run

“pure” rust:

rustc src/main.rs && ./main # for linux

Build project
#

cargo build # fast compilation
cargo build --release # slower compilation with optimizations

.
├── Cargo.lock
├── Cargo.toml
├── main
├── src
│   └── main.rs
└── target
    ├── debug
    │   ├── fibonacci
    └── release
        ├── fibonacci

Cargo.lock allows reproducible builds. target/release contains the release build, target/debug the default build. (fibonacci is the projects’s name and the executable’s name)

Also available: cargo test, cargo doc and cargo publish.

Types
#

Scalars
#

let number1: u8 = 1;
let number2: u16 = 10;
let number3: u32 = 100;
let number4: u64 = 1_000;
let number5: usize = 10_000;

let number6: i8 = -1;
let number7: i16 = -10;
let number8: i32 = -100; // default
let number9: i64 = -1_000;
let number0: isize = -10_000;

let decimal1: f32 = 3.14;
let decimal2: f64 = 2.78; // default

let b1: bool = true;
let b2: bool = false;

let char1: char = 'z';
let char2: char = '';

Compounds
#

let t1: (u8, u8, bool) = (1, 10, true);
let (x, y, z) = t1;

let arr = [1, 2, 3, 4, 5]; // FIXED size

Mutability
#

Rust’s default for variables is immutability. Therefore, once assigned the value of a variable cannot be altered. The mut keyword allows to define mutable variables:

let mut var = String::new()

Functions
#

fn main() {
    // main entryp point
}

Controls
#

IF-Else
#

if number < 5 {
    println!("True");
} else {
    println!("False")
}

Loops
#

  1. loop
loop {
    println!("Loop forever till break!");
    if condition {
        break;
    }
}
  1. while
let mut i = 0;
while i < 10 {
    println!("{}", i);
    i = i + 1;
}
  1. for
let mut sum = 0;
for n in 1..11 { // including start and excluding end
    sum += n;
}
println!("{}", sum);

let v = &["rust", "go", "c++"];
for text in v {
    println!("I like {}.", text);
}