Macro stack_buf::stack_vec[−][src]

macro_rules! stack_vec {
    () => { ... };
    ($ty: ty; $cap: literal) => { ... };
    ($elem:expr; $n:expr) => { ... };
    ($cap:literal# $elem:expr; $n:expr) => { ... };
    ($($x:expr),+ $(,)?) => { ... };
    ($cap:literal# $($x:expr),+ $(,)?) => { ... };
}

Creates a StackVec containing the arguments.

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

use stack_buf::{StackVec, stack_vec};

let vec: StackVec<i32, 8> = stack_vec![];
assert!(vec.is_empty());
assert_eq!(vec.capacity(), 8);

let vec = stack_vec![i32; 16];
assert!(vec.is_empty());
assert_eq!(vec.capacity(), 16);
  • Creates a StackVec containing a given list of elements:
use stack_buf::{StackVec, stack_vec};

let vec = stack_vec![128#1, 2, 3];
assert_eq!(vec.capacity(), 128);
assert_eq!(vec[0], 1);
assert_eq!(vec[1], 2);
assert_eq!(vec[2], 3);

let vec = stack_vec![1, 2, 3];
assert_eq!(vec.capacity(), 3);
  • Creates a StackVec from a given element and size:
use stack_buf::{StackVec, stack_vec};

let v = stack_vec![0x8000#1; 3];
assert_eq!(v.as_slice(), [1, 1, 1]);
assert_eq!(v.capacity(), 0x8000);

let v = stack_vec![1; 3];
assert_eq!(v.capacity(), 3);

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.

This will use clone to duplicate an expression, so one should be careful using this with types having a nonstandard Clone implementation. For example, stack_vec![Rc::new(1); 5] will create a vector of five references to the same boxed integer value, not five references pointing to independently boxed integers.