Trait cuprate_database::Key

pub trait Key: Storable + Sized {
    type Primary: Storable;

    // Provided method
    fn compare(left: &[u8], right: &[u8]) -> Ordering { ... }
}

Database Table key metadata.

Purely compile time information for database table keys.

Required Associated Types

type Primary: Storable

The primary key type.

Provided Methods

fn compare(left: &[u8], right: &[u8]) -> Ordering

Compare 2 Key’s against each other.

By default, this does a straight byte comparison, not a comparison of the key’s value.

assert_eq!(
    <u64 as Key>::compare([0].as_slice(), [1].as_slice()),
    std::cmp::Ordering::Less,
);
assert_eq!(
    <u64 as Key>::compare([1].as_slice(), [1].as_slice()),
    std::cmp::Ordering::Equal,
);
assert_eq!(
    <u64 as Key>::compare([2].as_slice(), [1].as_slice()),
    std::cmp::Ordering::Greater,
);

Object Safety

This trait is not object safe.

Implementors

impl<T> Key for T

where T: Storable + Sized,

type Primary = T