crdts/
gset.rs

1use core::convert::Infallible;
2use std::collections::BTreeSet;
3
4use serde::{Deserialize, Serialize};
5
6use crate::{CmRDT, CvRDT};
7
8/// A `GSet` is a grow-only set.
9#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
10pub struct GSet<T: Ord> {
11    value: BTreeSet<T>,
12}
13
14impl<T: Ord> Default for GSet<T> {
15    fn default() -> Self {
16        GSet::new()
17    }
18}
19
20impl<T: Ord> From<GSet<T>> for BTreeSet<T> {
21    fn from(gset: GSet<T>) -> BTreeSet<T> {
22        gset.value
23    }
24}
25
26impl<T: Ord> CvRDT for GSet<T> {
27    type Validation = Infallible;
28
29    fn validate_merge(&self, _other: &Self) -> Result<(), Self::Validation> {
30        Ok(())
31    }
32
33    /// Merges another `GSet` into this one.
34    ///
35    /// # Examples
36    ///
37    /// ```rust
38    /// use crdts::{GSet, CvRDT, CmRDT};
39    /// let (mut a, mut b) = (GSet::new(), GSet::new());
40    /// a.insert(1);
41    /// b.insert(2);
42    /// a.merge(b);
43    /// assert!(a.contains(&1));
44    /// assert!(a.contains(&2));
45    /// ```
46    fn merge(&mut self, other: Self) {
47        other.value.into_iter().for_each(|e| self.insert(e))
48    }
49}
50
51impl<T: Ord> CmRDT for GSet<T> {
52    type Op = T;
53    type Validation = Infallible;
54
55    fn validate_op(&self, _op: &Self::Op) -> Result<(), Self::Validation> {
56        Ok(())
57    }
58
59    fn apply(&mut self, op: Self::Op) {
60        self.insert(op);
61    }
62}
63
64impl<T: Ord> GSet<T> {
65    /// Instantiates an empty `GSet`.
66    pub fn new() -> Self {
67        Self {
68            value: BTreeSet::new(),
69        }
70    }
71
72    /// Inserts an element into this `GSet`.
73    ///
74    /// # Examples
75    ///
76    /// ```rust
77    /// use crdts::GSet;
78    /// let mut a = GSet::new();
79    /// a.insert(1);
80    /// assert!(a.contains(&1));
81    /// ```
82    pub fn insert(&mut self, element: T) {
83        self.value.insert(element);
84    }
85
86    /// Returns `true` if the `GSet` contains the element.
87    ///
88    /// # Examples
89    ///
90    /// ```rust
91    /// use crdts::GSet;
92    /// let mut a = GSet::new();
93    /// a.insert(1);
94    /// assert!(a.contains(&1));
95    /// ```
96    pub fn contains(&self, element: &T) -> bool {
97        self.value.contains(element)
98    }
99
100    /// Returns the `BTreeSet` for this `GSet`.
101    ///
102    /// # Examples
103    ///
104    /// ```rust
105    /// use crdts::GSet;
106    /// use std::collections::BTreeSet;
107    /// let mut a = GSet::new();
108    /// let mut b = BTreeSet::new();
109    /// for i in 1..10 {
110    ///     a.insert(i);
111    ///     b.insert(i);
112    /// }
113    ///
114    /// assert_eq!(a.read(), b);
115    /// ```
116    pub fn read(&self) -> BTreeSet<T>
117    where
118        T: Clone,
119    {
120        self.value.clone()
121    }
122}
crdts/gset.rs

crdts/
gset.rs
