Rust code shared from the playground

playground.rs

/*
Iterators and all functions that operates on iterators, are lazy by default.
Executes on demand.

Here in we have `println` that executes the lazy expression that is `largest`.
*/

fn main() {

    let a = [5,2,3,1,5,7,3];
    
    let mut index = 0;
    let largest = a.iter()
                    .cloned()
                    .enumerate()
                    .inspect(|&(x, y)| println!("about to filter: {} and {}", x, y))
                    .fold(0, |check, (x, y)| {
                        if y > check {
                            index = x;
                            y
                        } else {
                            check
                        }
                    });
    
    println!("largest is {} occurs at {}", largest, index);
    
}