use derive_new::new;
use futures::Stream;
use pin_project::pin_project;
use serde_closure::traits::FnMut;
use std::{
pin::Pin, task::{Context, Poll}
};
use super::Pipe;
#[pin_project]
#[derive(new)]
pub struct Map<P, F> {
#[pin]
pipe: P,
f: F,
}
impl<P: Stream, F> Stream for Map<P, F>
where
F: FnMut<(P::Item,)>,
{
type Item = F::Output;
#[inline]
fn poll_next(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Self::Item>> {
let mut self_ = self.project();
let (mut pipe, f) = (self_.pipe, &mut self_.f);
pipe.as_mut()
.poll_next(cx)
.map(|t| t.map(|t| f.call_mut((t,))))
}
}
impl<P: Pipe<Input>, F, Input> Pipe<Input> for Map<P, F>
where
F: FnMut<(P::Output,)>,
{
type Output = F::Output;
#[inline]
fn poll_next(
self: Pin<&mut Self>, cx: &mut Context, mut stream: Pin<&mut impl Stream<Item = Input>>,
) -> Poll<Option<Self::Output>> {
let mut self_ = self.project();
let (mut pipe, f) = (self_.pipe, &mut self_.f);
pipe.as_mut()
.poll_next(cx, stream.as_mut())
.map(|t| t.map(|t| f.call_mut((t,))))
}
}