Dev Notes

Software Development Resources by David Egan.

Rust Vectors


Rust
David Egan

The vec! macro makes initializing vectors convenient:

fn main() {
    let expected = vec![
        0x77, 0xd6, 0x57, 0x62, 0x38, 0x65, 0x7b, 0x20,
        0x3b, 0x19, 0xca, 0x42, 0xc1, 0x8a, 0x04, 0x97,];
    print_vec(&expected);
}

Initialize a vector of size n = 5 setting each element to 42:

let mut my_vec = vec![42; 5]; // Note semicolon seperator

Get an index within a for loop using .iter().enumerate():

fn print_vec(v: &Vec<u8>) {
    print!("[");
    for (i, el) in v.iter().enumerate() {
        if i != 0 {print!(", ")}
        print!("{}", el);
    }
    print!("]");
}

Initialize a Vector with Values

fn main() {
    let expected = vec![
        0x77, 0xd6, 0x57, 0x62, 0x38, 0x65, 0x7b, 0x20,
        0x3b, 0x19, 0xca, 0x42, 0xc1, 0x8a, 0x04, 0x97,];
    
    print_vec(&expected);

    // Initialize a 5 element vector, each element set to 42
    let my_vec = vec![42; 5];
    print_vec(&my_vec);
}

fn print_vec(v: &Vec<u8>) {
    print!("[");
    for (i, el) in v.iter().enumerate() {
        if i != 0 {print!(", ")}
        print!("{}", el);
    }
    print!("]\n");
}

Initialize an Array

// Array of 32 u8, each element set to 0
let mut result: [u8; 32] = [0; 32];
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