struct Struct {}

trait Trait {
    type S;
    const S:usize;
}
impl Trait for Struct {
    type S = i32;
    const S:usize = std::mem::size_of::<Struct>();

}
/*
fn i_from_slice<T:Trait>(slice: &[u8]) -> Option<T>

{
    match slice.len() {
        T::S => {
            let mut buf = [0; T::S];
            buf.copy_from_slice(slice);
            Some(unsafe { std::mem::transmute_copy(&buf) })
        }
        _ => None,
    }
}
*/
fn main() {
    println!("Hello, world!");
}