immut_list

immutable persistent list

```rust extern crate immutlist; extern crate datastructure_traits;

use immutlist::ImmutList; use datastructure_traits::*;

fn main() { let mut a = ImmutList::new();

for i in 0..32 {
    a = a.push(i);
}

let mut index = 32;
for i in &a {
    index -= 1;
    assert_eq!(i, &index);
}

println!("{:?}", a);

} ```