vortex_expr/
dyn_traits.rs

1// SPDX-License-Identifier: Apache-2.0
2// SPDX-FileCopyrightText: Copyright the Vortex contributors
3
4use std::any::Any;
5
6// TODO(adam): Look into having a similar setup as dyn-hash that will allow deriving `PartialEq` for structs
7// that have `Arc<dyn Trait>` fields.
8/// Allows comparing dyn-compatible objects, like [`ExprRef`](crate::ExprRef).
9pub trait DynEq {
10    fn dyn_eq(&self, other: &dyn Any) -> bool;
11}
12
13impl<T: Eq + Any> DynEq for T {
14    fn dyn_eq(&self, other: &dyn Any) -> bool {
15        Some(self) == other.downcast_ref::<Self>()
16    }
17}
18
19#[cfg(test)]
20mod tests {
21    use std::any::Any;
22    use std::fmt::Debug;
23
24    use super::DynEq;
25
26    trait MyTrait: DynEq + Debug + Any {}
27
28    impl MyTrait for u32 {}
29
30    impl MyTrait for u64 {}
31
32    impl PartialEq for dyn MyTrait {
33        fn eq(&self, other: &Self) -> bool {
34            self.dyn_eq(other)
35        }
36    }
37
38    #[test]
39    fn test_dyn_eq() {
40        let var_w = &2_u32 as &dyn MyTrait;
41        let var_x = &5_u32 as &dyn MyTrait;
42        let var_y = &5_u32 as &dyn MyTrait;
43        let var_z = &5_u64 as &dyn MyTrait;
44
45        // Same value, same type
46        assert_eq!(var_x, var_y);
47        // Different value, same type
48        assert_ne!(var_w, var_x);
49        // Same value, different type
50        assert_ne!(var_y, var_z);
51    }
52}
vortex_expr/dyn_traits.rs

vortex_expr/
dyn_traits.rs
