Code shared from the Rust Playground

playground.rs

macro_rules! assert_matches {
    ($e:expr, $($pat:pat)|+ $(if $cond:expr)?) => {
        match $e {
            $($pat)|+ $(if $cond)? => (),
            ref e => panic!("assertion failed: `{:?}` does not match `{}`",
            e, stringify!($($pat)|+ $(if $cond)?))
        }
    };
}

fn main() {
    assert_matches!(Some(3), Some(_));
    assert_matches!(Some(3), Some(3) | None | Some(2));

    assert_matches!(Err(3), Ok(x) | Err(x) if x >= 3);

    assert_matches!(&[3, 4][..], &[3, x] | &[x, 3] if x > 4);
}