Does Rust have a way to apply a function/method to each element in an array or vector?

Question

Does the Rust language have a way to apply a function to each element in an array or vector?

I know in Python there is the map() function which performs

Answer 1

Since Rust 1.21, the std::iter::Iterator trait defines a for_each() combinator which can be used to apply an operation to each element in the collection. It is eager (not lazy), so collect() is not needed:

fn main() {
    let mut vec = vec![1, 2, 3, 4, 5];
    vec.iter_mut().for_each(|el| *el *= 2);
    println!("{:?}", vec);
}

The above code prints [2, 4, 6, 8, 10] to the console.

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