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// 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);
}
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