5. Compound types: tuples and arrays

tuples_arrays.md

5. Compound types: tuples and arrays

• Tuple type and syntax of tuples
• Printing
• Tuples as argument types, access to components
• Tuples as return values
• Destructuring tuples
• Array type and array syntax
• Printing
• Bounds checking at compile time
• Bounds checking at run time
• Array slices
• Bounds checking the same

Tuples

fn f(a : (u64, u32)) -> (u32, u64) {
    (a.1, a.0)
}

fn main() {
    let a : (u64, u32) = (1, 2);
    let b : (i32, String) = (17, "abc".to_string());
    println!("{:?} {:?}", a, b);
    println!("{:?} {}", f(a), b.1);
    let (c, d) = f(a);
    println!("{} {}", c, d);
}

Arrays

fn main() {
    let a : [u16; 3] = [1, 2, 3];
    let args : Vec<String> = std::env::args().collect();
    println!("{:?}", args);
    let b = usize::from_str_radix(&args[1], 10).unwrap();
    println!("{}", a[b]);
}

Slicing works as for strings:

fn main() {
    let a : [u16; 3] = [1, 2, 3];
    let args : Vec<String> = std::env::args().collect();
    println!("{:?}", args);
    let b = usize::from_str_radix(&args[1], 10).unwrap();
    println!("{}", a[b]);
    let c = &args[1..3];
    println!("{:?}", c);
}

Even mutable slices are allowed:

fn main() {
    let a : [u16; 3] = [1, 2, 3];
    let mut args : Vec<String> = std::env::args().collect();
    println!("{:?}", args);
    let b = usize::from_str_radix(&args[1], 10).unwrap();
    println!("{}", a[b]);
    let c = &mut args[1..3];
    c[0] = "abc".to_string();
    println!("{:?}", c);
    println!("{:?}", args);
}

References:

• Rust book: https://doc.rust-lang.org/book/ch03-02-data-types.html#compound-types
• Rust book: https://doc.rust-lang.org/book/ch04-03-slices.html
• Video: https://youtu.be/awZFzOvYtGA
• Overview: https://gist.github.com/max-itzpapalotl/18f7675a60f6f9603250367bcb63992e