omango_util/
defer.rs

1// Copyright (c) 2024 Trung Tran <tqtrungse@gmail.com>
2//
3// Permission is hereby granted, free of charge, to any person obtaining a copy
4// of this software and associated documentation files (the "Software"), to deal
5// in the Software without restriction, including without limitation the rights
6// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
7// copies of the Software, and to permit persons to whom the Software is
8// furnished to do so, subject to the following conditions:
9//
10// The above copyright notice and this permission notice shall be included in all
11// copies or substantial portions of the Software.
12//
13// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
18// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
19// SOFTWARE.
20
21pub struct Defer<F: FnOnce()> {
22    f: Option<F>,
23}
24
25impl<F: FnOnce()> Defer<F> {
26    #[inline(always)]
27    pub fn new(f: F) -> Defer<F> {
28        Defer { f: Some(f) }
29    }
30}
31
32impl<F: FnOnce()> Drop for Defer<F> {
33    #[inline(always)]
34    fn drop(&mut self) {
35        if let Some(f) = self.f.take() {
36            f();
37        }
38    }
39}
40
41#[cfg(test)]
42mod test {
43    #[test]
44    fn test() {
45        fn defer() {
46            let a = 4u32;
47            let _df = crate::defer::Defer::new(|| {
48                assert_eq!(1u32, a);
49            });
50        }
51
52        let result = std::panic::catch_unwind(|| {
53            defer();
54        });
55        
56        assert!(result.is_err());
57    }
58}
omango_util/defer.rs

omango_util/
defer.rs
