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//@ run-pass
//@ edition:2021
use Foo::*;
#[allow(dead_code)]
#[derive(Eq, PartialEq, Debug)]
enum Foo {
A(u64),
B(u64),
C,
D,
}
macro_rules! foo {
($orpat:pat, $val:expr) => {
match $val {
x @ ($orpat) => x, // leading vert would not be allowed in $orpat
_ => B(0xDEADBEEFu64),
}
};
}
macro_rules! bar {
($orpat:pat, $val:expr) => {
match $val {
$orpat => 42, // leading vert allowed here
_ => 0xDEADBEEFu64,
}
};
}
fn main() {
// Test or-pattern.
let y = foo!(A(_)|B(_), A(32));
assert_eq!(y, A(32));
// Leading vert in or-pattern.
let y = bar!(|C| D, C);
assert_eq!(y, 42u64);
}
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