prettyplease/
ring.rs

Help
1use std::collections::VecDeque;
2use std::ops::{Index, IndexMut, Range};
3
4pub struct RingBuffer<T> {
5    data: VecDeque<T>,
6    // Abstract index of data[0] in infinitely sized queue
7    offset: usize,
8}
9
10impl<T> RingBuffer<T> {
11    pub fn new() -> Self {
12        RingBuffer {
13            data: VecDeque::new(),
14            offset: 0,
15        }
16    }
17
18    pub fn is_empty(&self) -> bool {
19        self.data.is_empty()
20    }
21
22    pub fn len(&self) -> usize {
23        self.data.len()
24    }
25
26    pub fn push(&mut self, value: T) -> usize {
27        let index = self.offset + self.data.len();
28        self.data.push_back(value);
29        index
30    }
31
32    pub fn clear(&mut self) {
33        self.data.clear();
34    }
35
36    pub fn index_range(&self) -> Range<usize> {
37        self.offset..self.offset + self.data.len()
38    }
39
40    pub fn first(&self) -> &T {
41        &self.data[0]
42    }
43
44    pub fn first_mut(&mut self) -> &mut T {
45        &mut self.data[0]
46    }
47
48    pub fn pop_first(&mut self) -> T {
49        self.offset += 1;
50        self.data.pop_front().unwrap()
51    }
52
53    pub fn last(&self) -> &T {
54        self.data.back().unwrap()
55    }
56
57    pub fn last_mut(&mut self) -> &mut T {
58        self.data.back_mut().unwrap()
59    }
60
61    pub fn second_last(&self) -> &T {
62        &self.data[self.data.len() - 2]
63    }
64
65    pub fn pop_last(&mut self) {
66        self.data.pop_back().unwrap();
67    }
68}
69
70impl<T> Index<usize> for RingBuffer<T> {
71    type Output = T;
72    fn index(&self, index: usize) -> &Self::Output {
73        &self.data[index.checked_sub(self.offset).unwrap()]
74    }
75}
76
77impl<T> IndexMut<usize> for RingBuffer<T> {
78    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
79        &mut self.data[index.checked_sub(self.offset).unwrap()]
80    }
81}
prettyplease/ring.rs

prettyplease/
ring.rs
