Function display_utils::join

pub fn join<T, I, J>(iterator: I, joiner: J) -> Join<I::IntoIter, J> where
    T: Display,
    I: IntoIterator<Item = T>,
    I::IntoIter: Clone,
    J: Display, 

Concatenate iterator elements, separating each element pair with a given joiner.

Equivalent to slice::join.

The iterator must be cloneable, because Display objects may be printed multiple times.

let strings = &["hello", "wonderful", "world"];

let output = join(strings, ", ");
assert_eq!(output.to_string(), "hello, wonderful, world");