pub trait BestCandidate<Item: MetricSpace<Impl> + Clone, Impl>where
Self: Sized,{
type Output;
// Required methods
fn consider(
&mut self,
item: &Item,
distance: Item::Distance,
candidate_index: usize,
user_data: &Item::UserData,
);
fn distance(&self) -> Item::Distance;
fn result(self, user_data: &Item::UserData) -> Self::Output;
}
Expand description
You can implement this if you want to peek at all visited elements
struct Impl;
struct ReturnByIndex<I: MetricSpace<Impl>> {
distance: I::Distance,
idx: usize,
}
impl<Item: MetricSpace<Impl> + Clone> BestCandidate<Item, Impl> for ReturnByIndex<Item> {
type Output = (usize, Item::Distance);
fn consider(&mut self, _: &Item, distance: Item::Distance, candidate_index: usize, _: &Item::UserData) {
if distance < self.distance {
self.distance = distance;
self.idx = candidate_index;
}
}
fn distance(&self) -> Item::Distance {
self.distance
}
fn result(self, _: &Item::UserData) -> Self::Output {
(self.idx, self.distance)
}
}
Required Associated Types§
Required Methods§
Sourcefn consider(
&mut self,
item: &Item,
distance: Item::Distance,
candidate_index: usize,
user_data: &Item::UserData,
)
fn consider( &mut self, item: &Item, distance: Item::Distance, candidate_index: usize, user_data: &Item::UserData, )
This is a visitor method. If the given distance is smaller than previously seen, keep the item (or its index).
UserData
is the same as for MetricSpace<Impl>
, and it’s ()
by default.
Dyn Compatibility§
This trait is not dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.