Rust Programming By Example
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Tuples

Tuples and structures are similar, except that tuples' fields are unnamed. Tuples are declared inside parentheses, with the element separated by a comma:

let tuple = (24, 42);
println!("({}, {})", tuple.0, tuple.1);

As you can see on the second line, we can access the elements of a tuple with .index, where index is a constant and this index starts at 0.

Tuples can be used to return multiple values from a function. For instance, the str::split_at() method returns two strings:

let (hello, world) = "helloworld".split_at(5);
println!("{}, {}!", hello, world);

Here, we assign the two elements of the tuple to the hello and world variables. We'll see why this works in the Pattern matching section.