wasefire_sync/
once.rs

1// Copyright 2023 Google LLC
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15/// Returns whether this statement was already executed.
16#[macro_export]
17macro_rules! executed {
18    () => {{
19        use $crate::{AtomicBool, Ordering};
20        static __X: AtomicBool = AtomicBool::new(false);
21        __X.swap(true, Ordering::Relaxed)
22    }};
23}
24
25#[cfg(test)]
26mod tests {
27    #[test]
28    fn executed_ok() {
29        fn test() -> bool {
30            executed!()
31        }
32        assert!(!test());
33        assert!(test());
34        assert!(test());
35    }
36}
wasefire_sync/once.rs

wasefire_sync/
once.rs
