Function format_xml::join

pub fn join<T>(sep: &'static str, collection: T) -> impl Display where
    T: IntoIterator,
    <T as IntoIterator>::Item: Display,
    <T as IntoIterator>::IntoIter: Clone, 

Displays an iterable with given separator between each item.

let result = join("--", &[1, 2, 3, 4]).to_string();
assert_eq!(result, "1--2--3--4");