FromIterator

FromIterator lets you build a collection from an Iterator.

fn main() {
    let primes = vec![2, 3, 5, 7];
    let prime_squares = primes.into_iter().map(|prime| prime * prime).collect::<Vec<_>>();
}

Iterator implements fn collect<B>(self) -> B where B: FromIterator<Self::Item>, Self: Sized

There are also implementations which let you do cool things like convert an Iterator<Item = Result<V, E>> into a Result<Vec<V>, E>.