dvcompute 2.0.0

Discrete event simulation library (sequential simulation)
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

// Copyright (c) 2020-2022  David Sorokin <davsor@mail.ru>, based in Yoshkar-Ola, Russia
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at https://mozilla.org/MPL/2.0/.

use crate::simulation::stream::*;

use dvcompute_utils::grc::Grc;

/// It represents the source of `Stream` computations.
#[must_use = "computations are lazy and do nothing unless to be run"]
#[derive(Clone)]
pub struct StreamFn<T> where T: 'static {
    gen: Grc<Box<dyn Fn() -> Stream<T>>>
}

impl<T> StreamFn<T> {

    /// Create a new source of computations.
    #[inline]
    pub fn new<F>(f: F) -> Self
        where F: Fn() -> Stream<T> + 'static
    {
        StreamFn {
            gen: Grc::new(Box::new(move || { f() }))
        }
    }

    /// Get the next computation.
    #[inline]
    pub fn next(&self) -> Stream<T> {
        (self.gen)()
    }

    /// Return the prefix of the stream of the specified length.
    pub fn take(&self, n: isize) -> Self
        where T: 'static
    {
        let gen = self.gen.clone();
        StreamFn {
            gen: Grc::new(Box::new(move || { gen().take(n) }))
        }
    }

    /// Return the suffix of the stream after the specified first elements.
    pub fn drop(&self, n: isize) -> Self
        where T: 'static
    {
        let gen = self.gen.clone();
        StreamFn {
            gen: Grc::new(Box::new(move || { gen().take(n) }))
        }
    }
}