o3 0.7.0

shared-nothing primitives
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39

use std::cell::Cell;

use crate::marker::ThreadBound;

pub struct ScratchVec<T> {
    slot: Cell<Vec<T>>,
    _thread: ThreadBound,
}

impl<T> ScratchVec<T> {
    pub const fn new() -> Self {
        Self {
            slot: Cell::new(Vec::new()),
            _thread: ThreadBound::NEW,
        }
    }

    pub fn take(&self) -> Vec<T> {
        let mut out = self.slot.take();
        out.clear();
        out
    }

    pub fn put(&self, mut buf: Vec<T>) {
        buf.clear();
        let slot = self.slot.take();
        if buf.capacity() > slot.capacity() {
            self.slot.set(buf);
        } else {
            self.slot.set(slot);
        }
    }
}

impl<T> Default for ScratchVec<T> {
    fn default() -> Self {
        Self::new()
    }
}