macro_rules! unwrap_as {
($e:expr, $p:path) => {
match $e {
$p(s) => s,
_ => panic!("Not a {}: {:?}", stringify!($p), $e),
}
}
}
macro_rules! assert_extent {
($parsed:expr, $extent:expr) => (assert_eq!(crate::HasExtent::extent(&$parsed), Extent::from($extent)));
}