sequence map

This commit is contained in:
Michael Sippel 2021-05-10 01:50:01 +02:00
parent 042fc6353c
commit c162e63b1d
Signed by: senvas
GPG key ID: F96CF119C34B64A6
2 changed files with 91 additions and 0 deletions

View file

@ -0,0 +1,90 @@
use {
std::sync::Arc,
std::sync::RwLock,
crate::{
sequence::{SequenceView},
core::{
Observer, ObserverExt, ObserverBroadcast,
View, ViewPort, InnerViewPort, OuterViewPort
}
}
};
//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>
impl<Item: 'static> OuterViewPort<dyn SequenceView<Item = Item>> {
pub fn map<
DstItem: 'static,
F: Fn(&Item) -> DstItem + Send + Sync + 'static
>(
&self,
f: F
) -> OuterViewPort<dyn SequenceView<Item = DstItem>> {
let port = ViewPort::new();
let map = Arc::new(RwLock::new(MapSequenceItem {
src_view: None,
f,
cast: port.inner().get_broadcast()
}));
self.add_observer(map.clone());
port.inner().set_view(Some(map));
port.into_outer()
}
}
//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>
pub struct MapSequenceItem<DstItem, SrcView, F>
where SrcView: SequenceView + ?Sized,
F: Fn(&SrcView::Item) -> DstItem + Send + Sync
{
src_view: Option<Arc<SrcView>>,
f: F,
cast: Arc<RwLock<ObserverBroadcast<dyn SequenceView<Item = DstItem>>>>
}
//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>
impl<DstItem, SrcView, F> View for MapSequenceItem<DstItem, SrcView, F>
where SrcView: SequenceView + ?Sized,
F: Fn(&SrcView::Item) -> DstItem + Send + Sync
{
type Msg = usize;
}
impl<DstItem, SrcView, F> SequenceView for MapSequenceItem<DstItem, SrcView, F>
where SrcView: SequenceView + ?Sized,
F: Fn(&SrcView::Item) -> DstItem + Send + Sync
{
type Item = DstItem;
fn len(&self) -> Option<usize> {
self.src_view.len()
}
fn get(&self, idx: &usize) -> Option<DstItem> {
self.src_view.get(idx).as_ref().map(|item| (self.f)(item))
}
}
//<<<<>>>><<>><><<>><<<*>>><<>><><<>><<<<>>>>
impl<DstItem, SrcView, F> Observer<SrcView> for MapSequenceItem<DstItem, SrcView, F>
where SrcView: SequenceView + ?Sized,
F: Fn(&SrcView::Item) -> DstItem + Send + Sync
{
fn reset(&mut self, view: Option<Arc<SrcView>>) {
let old_len = self.len();
self.src_view = view;
let new_len = self.len();
if let Some(len) = old_len { self.cast.notify_each(0 .. len ); }
if let Some(len) = new_len { self.cast.notify_each(0 .. len ); }
}
fn notify(&self, msg: &usize) {
self.cast.notify(msg);
}
}

View file

@ -1,6 +1,7 @@
pub mod seq2idx; pub mod seq2idx;
pub mod vec_buffer; pub mod vec_buffer;
pub mod map;
pub mod flatten; pub mod flatten;
pub use { pub use {