Closure with Box<T> arguments in Rust
Solution 1:
Here is an example how you can do that:
fn main() {
let a = Box::new(5);
let double = |x: Box<i32>| 2 * *x;
let b = double(a);
print!("{b}")
}
First, you need to specify the closure parameter type in this case. Instead of Box<i32>, you can also write Box<_>.
Next, you need to get the value owned by the Box via *x.