Trait Comparator

pub trait Comparator<Key: ?Sized> {
    // Required method
    fn cmp(&self, lhs: &Key, rhs: &Key) -> Ordering;
}

Interface for comparing keys (or entries) of a sorted collection.

The comparison function should provide a total order, just as Ord would.

Note that none of the axioms that define a total order require that two elements which compare as equal are “truly” equal in some more fundamental sense; that is, keys which are distinct (perhaps according to an Eq implementation) may compare as equal in the provided total order and corresponding equivalence relation.

Unsafe code is not allowed to rely on the correctness of implementations; that is, an incorrect Comparator implementation may cause severe logic errors, but must not cause memory unsafety.

Required Methods

fn cmp(&self, lhs: &Key, rhs: &Key) -> Ordering

Compare two keys (or entries) in a sorted collection.

This method is analogous to Ord::cmp, and should provide a total order.

Note that none of the axioms that define a total order require that two elements which compare as equal are “truly” equal in some more fundamental sense; that is, keys which are distinct (perhaps according to an Eq implementation) may compare as equal in the provided total order and corresponding equivalence relation.

Unsafe code is not allowed to rely on the correctness of implementations; that is, an incorrect implementation may cause severe logic errors, but must not cause memory unsafety.

Implementations on Foreign Types

impl<T, C, Key> Comparator<Key> for GenericContainer<T, C>

where T: ?Sized + Comparator<Key>, C: ?Sized + FragileContainer<T>,

fn cmp(&self, lhs: &Key, rhs: &Key) -> Ordering

Implementors

impl<Key: ?Sized + Ord> Comparator<Key> for DefaultComparator

impl<Key: ?Sized, C: FragileContainer<dyn Comparator<Key>>> Comparator<Key> for C