src/test/ui/or-patterns/slice-patterns.rs

   1 // Test or-patterns with slice-patterns
   2
   3 // run-pass
   4
   5 #[derive(Debug, PartialEq)]
   6 enum MatchArm {
   7     Arm(usize),
   8     Wild,
   9 }
  10
  11 #[derive(Debug)]
  12 enum Test {
  13     Foo,
  14     Bar,
  15     Baz,
  16     Qux,
  17 }
  18
  19 fn test(foo: &[Option<Test>]) -> MatchArm {
  20     match foo {
  21         [.., Some(Test::Qux | Test::Foo)] => MatchArm::Arm(0),
  22         [Some(Test::Foo), .., Some(Test::Baz | Test::Bar)] => MatchArm::Arm(1),
  23         [.., Some(Test::Bar | Test::Baz), _] => MatchArm::Arm(2),
  24         _ => MatchArm::Wild,
  25     }
  26 }
  27
  28 fn main() {
  29     let foo = vec![
  30         Some(Test::Foo),
  31         Some(Test::Bar),
  32         Some(Test::Baz),
  33         Some(Test::Qux),
  34     ];
  35
  36     // path 1a
  37     assert_eq!(test(&foo), MatchArm::Arm(0));
  38     // path 1b
  39     assert_eq!(test(&[Some(Test::Bar), Some(Test::Foo)]), MatchArm::Arm(0));
  40     // path 2a
  41     assert_eq!(test(&foo[..3]), MatchArm::Arm(1));
  42     // path 2b
  43     assert_eq!(test(&[Some(Test::Foo), Some(Test::Foo), Some(Test::Bar)]), MatchArm::Arm(1));
  44     // path 3a
  45     assert_eq!(test(&foo[1..3]), MatchArm::Arm(2));
  46     // path 3b
  47     assert_eq!(test(&[Some(Test::Bar), Some(Test::Baz), Some(Test::Baz), Some(Test::Bar)]),
  48         MatchArm::Arm(2));
  49     // path 4
  50     assert_eq!(test(&foo[4..]), MatchArm::Wild);
  51 }