String concatenate karat
let text1 = "hello".to_owned();
let text2 = text1 + " world";
println!("{}", text2);
Mackerel
let text1 = "hello".to_owned();
let text2 = text1 + " world";
println!("{}", text2);let s = concat!("test", 10, 'b', true); // concatenates string literals
assert_eq!(s, "test10btrue");