composable_indexes_core/
collection.rs

1use std::collections::HashMap;
2
3use crate::index::{Index, QueryEnv};
4
5#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
6pub struct Key {
7    pub id: u64,
8}
9
10pub struct Collection<In, Ix> {
11    index: Ix,
12    data: HashMap<Key, In>,
13    next_key_id: u64,
14}
15
16impl<'t, In, Ix> Collection<In, Ix>
17where
18    Ix: Index<'t, In>,
19{
20    pub fn new(ix: Ix) -> Self {
21        Collection {
22            data: HashMap::new(),
23            next_key_id: 0,
24            index: ix,
25        }
26    }
27
28    pub fn get(&self, key: Key) -> Option<&In> {
29        self.data.get(&key)
30    }
31
32    pub fn iter(&self) -> impl Iterator<Item = (&Key, &In)> {
33        self.data.iter()
34    }
35
36    pub fn insert(&mut self, value: In) -> Key {
37        let key = self.mk_key();
38        let existing = self.data.insert(key, value);
39
40        // There shouldn't be an existing key, as we just generated it
41        debug_assert!(existing.is_none());
42
43        self.index.insert(&Insert {
44            key,
45            new: &self.data[&key],
46        });
47
48        key
49    }
50
51    pub fn update<F>(&mut self, key: Key, f: F)
52    where
53        F: FnOnce(Option<&In>) -> In,
54    {
55        let existing = self.data.get(&key);
56        let new = f(existing);
57
58        match existing {
59            Some(existing) => {
60                self.index.update(&Update {
61                    key,
62                    new: &new,
63                    existing,
64                });
65                self.data.insert(key, new);
66            }
67            None => {
68                self.index.insert(&Insert { key, new: &new });
69                self.data.insert(key, new);
70            }
71        };
72    }
73
74    pub fn delete(&mut self, key: Key) {
75        match self.data.remove(&key) {
76            Some(ref existing) => {
77                self.index.remove(&Remove { key, existing });
78            }
79            None => {}
80        }
81    }
82
83    pub fn query(&'t self) -> Ix::Query<In> {
84        let env = QueryEnv { data: &self.data };
85        self.index.query(env)
86    }
87
88    pub fn len(&self) -> usize {
89        self.data.len()
90    }
91
92    fn mk_key(&mut self) -> Key {
93        let k = Key {
94            id: self.next_key_id,
95        };
96        self.next_key_id += 1;
97        k
98    }
99}
100
101#[derive(Clone)]
102pub struct Insert<'t, In> {
103    pub key: Key,
104    pub new: &'t In,
105}
106
107#[derive(Clone)]
108pub struct Update<'t, In> {
109    pub key: Key,
110    pub new: &'t In,
111    pub existing: &'t In,
112}
113
114#[derive(Clone)]
115pub struct Remove<'t, In> {
116    pub key: Key,
117    pub existing: &'t In,
118}
composable_indexes_core/collection.rs

composable_indexes_core/
collection.rs
