Function itertools::join

pub fn join<I>(iterable: I, sep: &str) -> String
where
    I: IntoIterator,
    I::Item: Display,

Combine all iterator elements into one String, separated by sep.

IntoIterator enabled version of Itertools::join.

use itertools::join;

assert_eq!(join(&[1, 2, 3], ", "), "1, 2, 3");