Rust by Example: Compound Types - Arrays

The array type is a compound type that allows you to store multiple values of the same type next to each other in memory. Arrays are useful when you want your data allocated on the stack rather than the heap or when you want to ensure you always have a fixed number of elements.
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fn main() {

Initialize array with values of same type

 
    let arr_inferred = [1, 2, 3, 4, 5];
    let arr_explicit: [i32; 5] = [1, 2, 3, 4, 5];
    println!("arr_inferred: {:?}", arr_inferred);
    println!("arr_explicit: {:?}", arr_explicit);

Initialize array with same value

 
    let arr_same = [3; 5];
    println!("arr_same: {:?}", arr_same);

We can access an array element directly by using brackets and the index of the value we want to access.

 
    let arr = [1, 2, 3, 4, 5];
    let first = arr[0];
    let second = arr[1];
    println!("first: {}, second: {}", first, second);

Slicing arrays

 
    let slice = &arr[1..3];
    let rest = &arr[1..];
    let all = &arr[..];
    println!("slice: {:?}", slice);
    println!("rest: {:?}", rest);
    println!("all: {:?}", all);

Iterating over arrays

 
    for element in arr.iter() {
        println!("element: {}", element);
    }
}

$ rustc arrays.rs
$ ./arrays
arr_inferred: [1, 2, 3, 4, 5]
arr_explicit: [1, 2, 3, 4, 5]
arr_same: [3, 3, 3, 3, 3]
first: 1, second: 2
slice: [2, 3]
rest: [2, 3, 4, 5]
all: [1, 2, 3, 4, 5]
element: 1
element: 2
element: 3
element: 4
element: 5
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