orx_parallel/infallible_use/
par_enum.rs

1use crate::ParUse;
2use crate::infallible_use::{ParUseIter, XapUseEnumByInput};
3use orx_concurrent_iter::{ConcurrentIter, enumerate::Enumerate};
4
5/// Adds index-value pairs to `ParUse` pipelines.
6///
7/// This is the `ParUse` counterpart of parallel `enumerate`, preserving the
8/// worker-local state while changing each item into `(index, item)`.
9///
10/// # Example
11///
12/// ```
13/// use orx_parallel::*;
14///
15/// let values: Vec<_> = (10..15)
16///     .into_par()
17///     .use_new(|_| ())
18///     .enumerate()
19///     .map(|_, (i, x)| i + x)
20///     .collect();
21///
22/// assert_eq!(values.len(), 5);
23/// assert!(values.contains(&10));
24/// assert!(values.contains(&18));
25/// ```
26pub trait EnumerateParUse: ParUse {
27    /// Transforms each item into `(index, item)` while keeping worker-local state.
28    ///
29    /// Indices are zero-based and correspond to the iterator order.
30    ///
31    /// # Example
32    ///
33    /// ```
34    /// use orx_parallel::*;
35    ///
36    /// let idx_sum: usize = (1..6)
37    ///     .into_par()
38    ///     .use_new(|_| ())
39    ///     .enumerate()
40    ///     .map(|_, (i, _)| i)
41    ///     .sum();
42    ///
43    /// assert_eq!(idx_sum, 10);
44    /// ```
45    fn enumerate(
46        self,
47    ) -> impl ParUse<
48        Using = Self::Using,
49        Use = Self::Use,
50        Item = (usize, Self::Item),
51        Input = Enumerate<Self::Input>,
52    >;
53}
54
55impl<P> EnumerateParUse for P
56where
57    P: ParUse,
58    P::Xap: XapUseEnumByInput,
59{
60    fn enumerate(
61        self,
62    ) -> impl ParUse<
63        Using = Self::Using,
64        Use = Self::Use,
65        Item = (usize, Self::Item),
66        Input = Enumerate<Self::Input>,
67    >
68    where
69        Self::Xap: XapUseEnumByInput,
70    {
71        let (u, iter, xap, exe, params) = self.destruct();
72        let iter = iter.enumerate();
73        let xap = xap.enumerate();
74        ParUseIter::new(u, iter, xap, exe, params)
75    }
76}
orx_parallel/infallible_use/par_enum.rs

orx_parallel/infallible_use/
par_enum.rs
