Macro vecc

macro_rules! vecc {
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr; if $cond:expr) => { ... };
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr) => { ... };
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr; if $cond:expr; $($tail:tt)+) => { ... };
    (@__ $acc:ident, $exp:expr; for $item:pat in $iter:expr; $($tail:tt)+) => { ... };
    ($exp:expr; $($tail:tt)+) => { ... };
}

Vector Comprehension

Creates a new Vec from the contents of the comprehension. Vector comprehensions are analogous to Python’s list comprehension.

Python code:

items = [4, 7, 2]

even_squares = [x*x for x in items if x % 2 == 0]

Rust equivalent code:

let items = [4, 7, 2];

let even_squares = vecc![x*x; for x in &items; if x % 2 == 0];

assert_eq!(even_squares, vec![16, 4]);