use derive_new::new;
use serde::{Deserialize, Serialize};
use super::{
folder_par_sink, FolderSync, FolderSyncReducer, FolderSyncReducerFactory, ParallelPipe, ParallelSink, SumFolder
};
#[derive(new)]
#[must_use]
pub struct Count<I> {
i: I,
}
impl_par_dist! {
impl<I: ParallelPipe<Source>, Source> ParallelSink<Source> for Count<I> {
folder_par_sink!(CountFolder, SumFolder<usize>, self, CountFolder::new(), SumFolder::new());
}
}
#[derive(Clone, Serialize, Deserialize, new)]
pub struct CountFolder;
impl<A> FolderSync<A> for CountFolder {
type Output = usize;
fn zero(&mut self) -> Self::Output {
0
}
fn push(&mut self, state: &mut Self::Output, _item: A) {
*state += 1;
}
}