struct Foo;
use std::io::Read;

fn main() {
    let data: Vec<u8> = vec![1,2,3,4,5];
    let mut data_slice = data.as_slice();
    let mut vec: Vec<u8> = vec![];
    let mut slice = vec.as_mut_slice();
    data_slice.read(&mut slice);

    assert_eq!(data, vec, "not equal");
}