How can I obtain the address of a closure in Rust?

let say_hello = || println!("hello");

How can I display the address of the closure?

>Solution :

You can use a raw pointer conversion:

fn main() {
    let say_hello = || println!("hello");
    let address = (&say_hello as *const _) as usize;
    println!("{address}");
}

Playground

Also using std::ptr::addr_of and casting again:

let same_address = std::ptr::addr_of!(say_hello) as usize;

Playground