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
//! Merges the contents of multiple streams.
use Data;
use dataflow::channels::pact::Pipeline;
use dataflow::{Stream, Scope};
use dataflow::operators::binary::Binary;
// NOTE : These used to have more exotic implementations that connected observers in a tangle.
// NOTE : It was defective when used with the Observer protocol, because it just forwarded open and
// NOTE : shut messages, without concern for the fact that there would be multiple opens and shuts,
// NOTE : from each of its inputs. This implementation does more staging of data, but should be
// NOTE : less wrong.
// NOTE : Observers don't exist any more, so maybe it could become a horrible tangle again! :D
// NOTE : Not clear that the tangle buys much, as buffers are simply passed along without copying.
/// Merge the contents of two streams.
pub trait Concat<G: Scope, D: Data> {
/// Merge the contents of two streams.
///
/// #Examples
/// ```
/// use timely::dataflow::operators::{ToStream, Concat, Inspect};
///
/// timely::example(|scope| {
///
/// let stream = (0..10).to_stream(scope);
/// stream.concat(&stream)
/// .inspect(|x| println!("seen: {:?}", x));
/// });
/// ```
fn concat(&self, &Stream<G, D>) -> Stream<G, D>;
}
impl<G: Scope, D: Data> Concat<G, D> for Stream<G, D> {
fn concat(&self, other: &Stream<G, D>) -> Stream<G, D> {
self.binary_stream(other, Pipeline, Pipeline, "Concat", |input1, input2, output| {
input1.for_each(|time, data| { output.session(&time).give_content(data); });
input2.for_each(|time, data| { output.session(&time).give_content(data); });
})
}
}
/// Merge the contents of multiple streams.
pub trait Concatenate<G: Scope, D: Data> {
/// Merge the contents of multiple streams.
///
/// #Examples
/// ```
/// use timely::dataflow::operators::{ToStream, Concatenate, Inspect};
///
/// timely::example(|scope| {
///
/// let streams = vec![(0..10).to_stream(scope),
/// (0..10).to_stream(scope),
/// (0..10).to_stream(scope)];
///
/// scope.concatenate(streams)
/// .inspect(|x| println!("seen: {:?}", x));
/// });
/// ```
fn concatenate(&self, Vec<Stream<G, D>>) -> Stream<G, D>;
}
impl<G: Scope, D: Data> Concatenate<G, D> for G {
fn concatenate(&self, mut sources: Vec<Stream<G, D>>) -> Stream<G, D> {
if let Some(mut result) = sources.pop() {
while let Some(next) = sources.pop() {
result = result.concat(&next);
}
result
}
else {
panic!("must pass at least one stream to concatenate");
}
}
}