core/context/
value.rs

1use std::any::{Any, TypeId};
2use std::collections::hash_map::DefaultHasher;
3use std::hash::{Hash, Hasher};
4
5/// 上下文 Value key 约束：可比较、可哈希、'static。
6pub trait ValueKey: Send + Sync + 'static {
7    fn equals(&self, other: &dyn ValueKey) -> bool;
8    fn hash_dyn(&self, state: &mut dyn Hasher);
9    fn type_id(&self) -> TypeId;
10    fn as_any(&self) -> &dyn Any;
11}
12
13impl<T> ValueKey for T
14where
15    T: Eq + Hash + Send + Sync + 'static,
16{
17    fn equals(&self, other: &dyn ValueKey) -> bool {
18        if Any::type_id(self) != other.type_id() {
19            return false;
20        }
21        other
22            .as_any()
23            .downcast_ref::<T>()
24            .map(|v| v == self)
25            .unwrap_or(false)
26    }
27
28    fn hash_dyn(&self, state: &mut dyn Hasher) {
29        let mut tid_hasher = DefaultHasher::new();
30        TypeId::of::<T>().hash(&mut tid_hasher);
31        let mut val_hasher = DefaultHasher::new();
32        Hash::hash(self, &mut val_hasher);
33        state.write_u64(tid_hasher.finish());
34        state.write_u64(val_hasher.finish());
35    }
36
37    fn type_id(&self) -> TypeId {
38        TypeId::of::<T>()
39    }
40
41    fn as_any(&self) -> &dyn Any {
42        self
43    }
44}
core/context/value.rs

core/context/
value.rs
