pub trait SignalMap {
type Key;
type Value;
// Required method
fn poll_map_change(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
) -> Poll<Option<MapDiff<Self::Key, Self::Value>>>;
}
pub trait SignalMap {
type Key;
type Value;
// Required method
fn poll_map_change(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
) -> Poll<Option<MapDiff<Self::Key, Self::Value>>>;
}