postage 0.5.0

An async channel library
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
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143

#![allow(dead_code)]

use pin_project::pin_project;
use std::marker::PhantomData;

use crate::stream::{PollRecv, Stream};

pub fn ready<T>(value: T) -> impl Stream<Item = T>
where
    T: Clone,
{
    crate::stream::repeat(value)
}

pub fn pending<T>() -> impl Stream<Item = T> {
    PendingStream::new()
}

pub fn closed<T>() -> impl Stream<Item = T> {
    ClosedStream::new()
}

pub fn from_iter<I>(iter: I) -> impl Stream<Item = I::Item>
where
    I: IntoIterator,
{
    IterStream::new(iter.into_iter())
}

pub fn from_poll_iter<I, T>(iter: I) -> impl Stream<Item = T>
where
    I: IntoIterator<Item = PollRecv<T>>,
{
    PollIterStream::new(iter.into_iter())
}

struct PendingStream<T> {
    _t: PhantomData<T>,
}

impl<T> PendingStream<T> {
    pub fn new() -> Self {
        Self { _t: PhantomData }
    }
}

impl<T> Stream for PendingStream<T> {
    type Item = T;

    fn poll_recv(
        self: std::pin::Pin<&mut Self>,
        _cx: &mut crate::Context<'_>,
    ) -> crate::stream::PollRecv<Self::Item> {
        PollRecv::Pending
    }
}
struct ClosedStream<T> {
    _t: PhantomData<T>,
}

impl<T> ClosedStream<T> {
    pub fn new() -> Self {
        Self { _t: PhantomData }
    }
}

impl<T> Stream for ClosedStream<T> {
    type Item = T;

    fn poll_recv(
        self: std::pin::Pin<&mut Self>,
        _cx: &mut crate::Context<'_>,
    ) -> crate::stream::PollRecv<Self::Item> {
        PollRecv::Closed
    }
}
#[pin_project]
pub struct IterStream<I: Iterator> {
    iter: I,
}

impl<I> IterStream<I>
where
    I: Iterator,
{
    pub fn new(iter: I) -> Self {
        Self { iter }
    }
}

impl<I> Stream for IterStream<I>
where
    I: Iterator,
{
    type Item = I::Item;

    fn poll_recv(
        self: std::pin::Pin<&mut Self>,
        _cx: &mut crate::Context<'_>,
    ) -> PollRecv<Self::Item> {
        let this = self.project();
        match this.iter.next() {
            Some(value) => PollRecv::Ready(value),
            None => PollRecv::Closed,
        }
    }
}

#[pin_project]
pub struct PollIterStream<I: Iterator, T> {
    iter: I,
    _t: PhantomData<T>,
}

impl<I, T> PollIterStream<I, T>
where
    I: Iterator,
{
    pub fn new(iter: I) -> Self {
        Self {
            iter,
            _t: PhantomData,
        }
    }
}

impl<I, T> Stream for PollIterStream<I, T>
where
    I: Iterator<Item = PollRecv<T>>,
{
    type Item = T;

    fn poll_recv(
        self: std::pin::Pin<&mut Self>,
        _cx: &mut crate::Context<'_>,
    ) -> PollRecv<Self::Item> {
        let this = self.project();
        match this.iter.next() {
            Some(poll) => poll,
            None => PollRecv::Closed,
        }
    }
}