src/test/run-pass/issues/issue-15104.rs

// run-pass
#![feature(slice_patterns)]

fn main() {
    assert_eq!(count_members(&[1, 2, 3, 4]), 4);
}

fn count_members(v: &[usize]) -> usize {
    match *v {
        []         => 0,
        [_]        => 1,
        [_, ref xs..] => 1 + count_members(xs)
    }
}