Join elements of vector into a string

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examples/vectors/join/src/main.rs

fn main() {
    let names = vec!["Foo", "Bar", "Baz"];
    println!("{:?}", names);

    let joined = names.join("");
    println!("{}", joined);

    let csv = names.join(",");
    println!("{}", csv);
}

["Foo", "Bar", "Baz"]
FooBarBaz
Foo,Bar,Baz