给出以下代码,为什么每个向量的capacity
是0而不是chunk_size
?
#[test]
fn test() {
let chunk_size = 1024;
let data: Vec<Vec<u8>> = vec![Vec::with_capacity(chunk_size); 2];
assert_eq!(data[0].capacity(), chunk_size);
assert_eq!(data[1].capacity(), chunk_size);
}
playground 链接:https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=0c40515b164044621c369adef1090c6e