Arrays and tuples

In rust, the data types of all array element have to the same. We can declare an array by:

let x = [1, 2, 3];

We can access the elements of the array by:

first_element = x[0]

If we want to modify the elements of the array, we need to use the keyword mut during declaration:

let mut x = [1, 2, 3];
x[0] = 4

Some more example of array:

src/06-arrays/main.rs
fn main() {
    let arr1 = [1, 2, 3];
    println!("Second element of arr1 = {}", arr1[1]);
    println!("First element of arr1 = {:?}", arr1.get(0));
    // get method returns Options<T> enum (Some(T) or None), we can print using
    // debug formatter

    let mut arr2 = [2, 4, 6];
    arr2[0] = 0;
    println!("First element of arr2 = {}", arr2[0]);

    // swap two elements of an array
    println!("arr2 before swap: {:?}", arr2);
    // this way you can print a whole array
    arr2.swap(1, 2);
    println!("arr2 after swap: {:?}", arr2);

    // defining array without initialization
    let arr3: [i32; 5]; // array of size 5 containing 32 bit integers
    arr3 = [1; 5]; // initialize all elements with same number
    println!("3rd element of arr3 = {}", arr3[2]);

    let len_arr2 = arr2.len(); // data type of len is `usize`

    for i in 0..len_arr2 {
        println!("{}", arr2[i]);
    }

    // multi-dimensional arrays
    let arr4 = [[1, 2, 3], [4, 5, 6]];
    println!("arr4[1][1] = {}", arr4[1][1]);

    // initialize a multi-dimensional array;
    let arr5: [[[i32; 5]; 6]; 10];
    // notice inner most dimension size is 5, and outer most 10
    arr5 = [[[0; 5]; 6]; 10];
    println!("arr5[9][4][3] = {}", arr5[9][4][3]);
}

Tuples

Tuples elements can have different data types. Tuple elements are accessed using dot notation.

src/06-tuples/main.rs
fn main() {
    let data = (35, 185, "Pranab"); // order of elements in a tuple matters
    let first_item = data.0;

    println!("First element of the tuple = {}", first_item);
    println!("data = {:?}", data); // print whole tuple using debug formatter

    // destructuring
    let (age, height, name) = data;
    println!("Name: {name}, Age = {age}, Height = {height}");
}

Tuples​

Tuples