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// Test or-patterns with slice-patterns
//@ run-pass
#[derive(Debug, PartialEq)]
enum MatchArm {
Arm(usize),
Wild,
}
#[derive(Debug)]
enum Test {
Foo,
Bar,
Baz,
Qux,
}
fn test(foo: &[Option<Test>]) -> MatchArm {
match foo {
[.., Some(Test::Qux | Test::Foo)] => MatchArm::Arm(0),
[Some(Test::Foo), .., Some(Test::Baz | Test::Bar)] => MatchArm::Arm(1),
[.., Some(Test::Bar | Test::Baz), _] => MatchArm::Arm(2),
_ => MatchArm::Wild,
}
}
fn main() {
let foo = vec![
Some(Test::Foo),
Some(Test::Bar),
Some(Test::Baz),
Some(Test::Qux),
];
// path 1a
assert_eq!(test(&foo), MatchArm::Arm(0));
// path 1b
assert_eq!(test(&[Some(Test::Bar), Some(Test::Foo)]), MatchArm::Arm(0));
// path 2a
assert_eq!(test(&foo[..3]), MatchArm::Arm(1));
// path 2b
assert_eq!(test(&[Some(Test::Foo), Some(Test::Foo), Some(Test::Bar)]), MatchArm::Arm(1));
// path 3a
assert_eq!(test(&foo[1..3]), MatchArm::Arm(2));
// path 3b
assert_eq!(test(&[Some(Test::Bar), Some(Test::Baz), Some(Test::Baz), Some(Test::Bar)]),
MatchArm::Arm(2));
// path 4
assert_eq!(test(&foo[4..]), MatchArm::Wild);
}
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