dbuff 0.1.0

Double-buffered state with async command chains, streaming, and keyed task pools for ratatui applications
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
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68

use dbuff::*;
use std::time::Duration;

#[derive(Debug, Clone)]
struct AppServices {
    prefix: String,
    multiplier: i32,
}

#[derive(Debug, Clone, Default)]
struct AppData {
    greeting: String,
    value: i32,
}

#[derive(Debug, Clone, wherror::Error)]
#[error(debug)]
struct CmdError;

struct Greet(String);

#[async_trait::async_trait]
impl Command<AppServices> for Greet {
    type Output = String;
    type Error = CmdError;

    async fn execute(self, services: AppServices) -> Result<Self::Output, Self::Error> {
        Ok(format!("{} {}", services.prefix, self.0))
    }
}

struct Scale(i32);

#[async_trait::async_trait]
impl Command<AppServices> for Scale {
    type Output = i32;
    type Error = CmdError;

    async fn execute(self, services: AppServices) -> Result<Self::Output, Self::Error> {
        Ok(self.0 * services.multiplier)
    }
}

#[tokio::main]
async fn main() {
    let rt = tokio::runtime::Handle::current();
    let services = AppServices {
        prefix: ">>".into(),
        multiplier: 3,
    };

    let (domain, write_handle) =
        SharedDomainData::with_coalesce(AppData::default(), Duration::from_micros(500));
    tokio::spawn(write_handle.run());

    drop(domain.bind(services, rt.clone())
        .exec(Greet("world".into()), |d, v: &String| d.greeting.clone_from(v))
        .exec(Scale(10), |d, v: &i32| d.value = *v)
        .go());

    tokio::time::sleep(Duration::from_millis(10)).await;

    let guard = domain.read();
    assert_eq!(guard.greeting, ">> world");
    assert_eq!(guard.value, 30);
    println!("greeting = {}", guard.greeting);
    println!("value = {}", guard.value);
}