I have the following two implementations of extracting the largest item out of a collection, one implementation is for a LinkedList and one for a Vec.

Live Demo:

use std::collections::LinkedList;

fn get_largest_in_list(coll: &LinkedList<i32>) -> i32 {
    let mut largest: i32 = 0;
    for &item in coll {
        if item > largest {
            largest = item;
        }
    }
      
    largest
}

macro_rules! linked_list {
    ($($e:expr),*) => {{
        let mut list = LinkedList::new();
        $(list.push_back($e);)*
        list
    }};
}

fn get_largest_in_vec(coll: &Vec<i32>) -> i32 {
    let mut largest: i32 = 0;
    for &item in coll {
        if item > largest {
            largest = item;
        }
    }

    largest
}

pub fn main() {
    // let mut s = String::from("hello world");

    // let len = s.len();

    let myvec: Vec<i32> = vec![9, 4, 2, 13, 81, 92];
    let largest: i32 = get_largest_in_vec(&myvec);
    println!("The largest item in vector is {:?}", largest);


    let mylist: LinkedList<i32> = linked_list![10, 15, 2, 3, 7, 100];
    let largest: i32 = get_largest_in_list(&mylist);
    println!("The largest item in list is {:?}", largest);

    // println!("{:?}", myvec);
}

You can see that there is quite some amount of code duplication. What I want to do now is to write a generic function get_largest that works for both LinkedList and Vec. What would be the rustacean way to do this?

(side question: It appears there is no linked_list! macro in the standard library, so I had to write my own.. Why is that?)