Trait Comparator

pub trait Comparator<K>
where
    K: Copy,
{
    // Required method
    fn cmp(&self, a: K, b: K) -> Ordering;

    // Provided method
    fn search(&self, k: K, s: &[K]) -> Result<usize, usize> { ... }
}

Key comparator.

Keys don’t need to implement Ord. They are compared using a comparator object which provides a context for comparison.

Required Methods

fn cmp(&self, a: K, b: K) -> Ordering

Compare keys a and b.

This relation must provide a total ordering or the key space.

Provided Methods

fn search(&self, k: K, s: &[K]) -> Result<usize, usize>

Binary search for k in an ordered slice.

Assume that s is already sorted according to this ordering, search for the key k.

Returns Ok(idx) if k was found in the slice or Err(idx) with the position where it should be inserted to preserve the ordering.

Implementations on Foreign Types

impl<K> Comparator<K> for ()

where K: Copy + Ord,

Trivial comparator that doesn’t actually provide any context.

fn cmp(&self, a: K, b: K) -> Ordering

Implementors