collections::vec!

macro_rules! vec {
    ($elem:expr; $n:expr) => (
        $crate::vec::from_elem($elem, $n)
    );
    ($($x:expr),*) => (
        <[_]>::into_vec($crate::boxed::Box::new([$($x),*]))
    );
    ($($x:expr,)*) => (vec![$($x),*])
}

Creates a Vec containing the arguments.

vec! allows Vecs to be defined with the same syntax as array expressions. There are two forms of this macro:

• Create a Vec containing a given list of elements:

fn main() { let v = vec![1, 2, 3]; assert_eq!(v[0], 1); assert_eq!(v[1], 2); assert_eq!(v[2], 3); }

let v = vec![1, 2, 3];
assert_eq!(v[0], 1);
assert_eq!(v[1], 2);
assert_eq!(v[2], 3);

• Create a Vec from a given element and size:

fn main() { let v = vec![1; 3]; assert_eq!(v, [1, 1, 1]); }

let v = vec![1; 3];
assert_eq!(v, [1, 1, 1]);

Note that unlike array expressions this syntax supports all elements which implement Clone and the number of elements doesn't have to be a constant.