scsys_core/stores/
kv.rs

1/*
2    Appellation: store <module>
3    Contrib: FL03 <jo3mccain@icloud.com>
4*/
5#![allow(unused_macros)]
6
7pub trait Entry<'a> {
8    type Key;
9    type Value;
10
11    fn key(&self) -> &Self::Key;
12
13    fn or_insert(self, default: Self::Value) -> &'a mut Self::Value;
14}
15
16pub trait Store<K, V> {
17    fn get(&self, key: &K) -> Option<&V>;
18
19    fn get_mut(&mut self, key: &K) -> Option<&mut V>;
20
21    fn insert(&mut self, key: K, value: V) -> Option<V>;
22
23    fn remove(&mut self, key: &K) -> Option<V>;
24}
25
26/*
27 ********* Implementations *********
28*/
29macro_rules! entry {
30    ($($prefix:ident)::* -> $call:ident($($arg:tt),*)) => {
31        $($prefix)::*::Entry::$call($($arg),*)
32    };
33
34}
35
36macro_rules! impl_entry {
37    ($($prefix:ident)::* where $($preds:tt)* ) => {
38
39        impl<'a, K, V> Entry<'a> for $($prefix)::*::Entry<'a, K, V> where $($preds)* {
40            type Key = K;
41            type Value = V;
42
43            fn key(&self) -> &Self::Key {
44                entry!($($prefix)::* -> key(self))
45            }
46
47            fn or_insert(self, default: Self::Value) -> &'a mut Self::Value {
48                entry!($($prefix)::* -> or_insert(self, default))
49            }
50        }
51
52    };
53
54}
55
56macro_rules! impl_store {
57    ($t:ty, where $($preds:tt)* ) => {
58
59        impl<K, V> Store<K, V> for $t where $($preds)* {
60            fn get(&self, key: &K) -> Option<&V> {
61                <$t>::get(self, &key)
62            }
63
64            fn get_mut(&mut self, key: &K) -> Option<&mut V> {
65                <$t>::get_mut(self, &key)
66            }
67
68            fn insert(&mut self, key: K, value: V) -> Option<V> {
69                <$t>::insert(self, key, value)
70            }
71
72            fn remove(&mut self, key: &K) -> Option<V> {
73                <$t>::remove(self, &key)
74            }
75        }
76
77    };
78}
79
80#[cfg(feature = "alloc")]
81impl_entry!(alloc::collections::btree_map where K: Ord);
82#[cfg(feature = "alloc")]
83impl_store!(alloc::collections::BTreeMap<K, V>, where K: Ord);
84
85#[cfg(feature = "std")]
86impl_entry!(std::collections::hash_map where K: Eq + core::hash::Hash);
87#[cfg(feature = "std")]
88impl_store!(std::collections::HashMap<K, V>, where K: Eq + core::hash::Hash);
scsys_core/stores/kv.rs

scsys_core/stores/
kv.rs
