Rust (programming language)

Rust icon

Rust is a programming language designed for systems, which are "software designed to provide a platform for other software". It is or was used to write operating system and web browser components, services such as OpenDNS and Tor, and game engines. It was made by former Mozilla engineer Graydon Hoare.

Applications

• Astrophysics
• GPU programming
• Simulation

Examples

Here is a hello world program in Rust.

// Define entry point.
fn main() {
    // Write to output.
    println!("Hello world!");
}

Here is an example of declaring a variable and writing its value to the output in Rust.

// Define entry point.
fn main() {
    // Assigns value 5 to the variable called x.
    let x = 5;

    // Writes the value of x to the output.
    println!("{}", x);
}

Here is an example of using if-else statement in Rust.

// Define entry point.
fn main() {
    // Assigns value 5 to the variable callex x.
    let x = 5;

    // Checks if the variable x is equal to 5, if it isn't, the code in the else block will execute instead.
    if x == 5 {
        println!("x is a 5!");
    } else {
        println!("x is not a 5!");
    }
}

Here is an example of using a loop statement that breaks after it reaches 7 in Rust.

// Define entry point.
fn main() {
    // Assigns value 0 to the variable called x.
    let counter = 0;

    // "Loop" loop runs forever until it reaches a break.
    loop {
        if counter == 7 {
            break
        }

        // Increases the value of counter by 1.
        counter += 1;
    }

    // Writes the value of counter to the output.
    println!("{}", counter);
}

Here is an example of a function that returns sum of two numbers in Rust.

// Define entry point.
fn main() {
    // Declares two variables with the data type of signed 32-bit integer.
    let x: i32 = 5;
    let y: i32 = 2;

    // Prints the sum of the variables x and y.
    println!("{}", sum(x, y));
}

/*
The `fn` keyword is used for defining functions, which is followed by the name of the function. 
Parameters are written in the parantheses, and are followed by a colon and its data type.
A data type of the returned value is put after the hyphen and right angle bracket.
If the expression is the last thing in the function's body, you don't need to use the `return` keyword and a semicolon.
*/
fn sum(x: i32, y: i32) -> i32 {
    x + y
}