| // Check that we expand multiple or-patterns from left to right. |
| |
| //@ run-pass |
| |
| fn search(target: (bool, bool, bool)) -> u32 { |
| let x = ((false, true), (false, true), (false, true)); |
| let mut guard_count = 0; |
| match x { |
| ((a, _) | (_, a), (b @ _, _) | (_, b @ _), (c @ false, _) | (_, c @ true)) |
| if { |
| guard_count += 1; |
| (a, b, c) == target |
| } => |
| { |
| guard_count |
| } |
| _ => unreachable!(), |
| } |
| } |
| |
| // Equivalent to the above code, but hopefully easier to understand. |
| fn search_old_style(target: (bool, bool, bool)) -> u32 { |
| let x = ((false, true), (false, true), (false, true)); |
| let mut guard_count = 0; |
| match x { |
| ((a, _), (b @ _, _), (c @ false, _)) |
| | ((a, _), (b @ _, _), (_, c @ true)) |
| | ((a, _), (_, b @ _), (c @ false, _)) |
| | ((a, _), (_, b @ _), (_, c @ true)) |
| | ((_, a), (b @ _, _), (c @ false, _)) |
| | ((_, a), (b @ _, _), (_, c @ true)) |
| | ((_, a), (_, b @ _), (c @ false, _)) |
| | ((_, a), (_, b @ _), (_, c @ true)) |
| if { |
| guard_count += 1; |
| (a, b, c) == target |
| } => |
| { |
| guard_count |
| } |
| _ => unreachable!(), |
| } |
| } |
| |
| // Check that a dummy or-pattern also leads to running the guard multiple times. |
| fn search_with_dummy(target: (bool, bool)) -> u32 { |
| let x = ((false, true), (false, true), ()); |
| let mut guard_count = 0; |
| match x { |
| ((a, _) | (_, a), (b, _) | (_, b), _ | _) |
| if { |
| guard_count += 1; |
| (a, b) == target |
| } => |
| { |
| guard_count |
| } |
| _ => unreachable!(), |
| } |
| } |
| |
| fn main() { |
| assert_eq!(search((false, false, false)), 1); |
| assert_eq!(search((false, false, true)), 2); |
| assert_eq!(search((false, true, false)), 3); |
| assert_eq!(search((false, true, true)), 4); |
| assert_eq!(search((true, false, false)), 5); |
| assert_eq!(search((true, false, true)), 6); |
| assert_eq!(search((true, true, false)), 7); |
| assert_eq!(search((true, true, true)), 8); |
| |
| assert_eq!(search_old_style((false, false, false)), 1); |
| assert_eq!(search_old_style((false, false, true)), 2); |
| assert_eq!(search_old_style((false, true, false)), 3); |
| assert_eq!(search_old_style((false, true, true)), 4); |
| assert_eq!(search_old_style((true, false, false)), 5); |
| assert_eq!(search_old_style((true, false, true)), 6); |
| assert_eq!(search_old_style((true, true, false)), 7); |
| assert_eq!(search_old_style((true, true, true)), 8); |
| |
| assert_eq!(search_with_dummy((false, false)), 1); |
| assert_eq!(search_with_dummy((false, true)), 3); |
| assert_eq!(search_with_dummy((true, false)), 5); |
| assert_eq!(search_with_dummy((true, true)), 7); |
| } |
