std::vec!

( $ elem : expr ; $ n : expr ) => ( $ crate:: vec:: from_elem ( $ elem , $ n )
) ; ( $ ( $ x : expr ) , * ) => (
< [ _ ] as $ crate:: slice:: SliceExt > :: 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, vec![1, 1, 1]); }

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