Struct std::hash::BuildHasherDefault
1.7.0 · source · pub struct BuildHasherDefault<H>(_);Expand description
Used to create a default BuildHasher instance for types that implement
Hasher and Default.
BuildHasherDefault<H> can be used when a type H implements Hasher and
Default, and you need a corresponding BuildHasher instance, but none is
defined.
Any BuildHasherDefault is zero-sized. It can be created with
default. When using BuildHasherDefault with HashMap or
HashSet, this doesn’t need to be done, since they implement appropriate
Default instances themselves.
Examples
Using BuildHasherDefault to specify a custom BuildHasher for
HashMap:
use std::collections::HashMap;
use std::hash::{BuildHasherDefault, Hasher};
#[derive(Default)]
struct MyHasher;
impl Hasher for MyHasher {
fn write(&mut self, bytes: &[u8]) {
// Your hashing algorithm goes here!
unimplemented!()
}
fn finish(&self) -> u64 {
// Your hashing algorithm goes here!
unimplemented!()
}
}
type MyBuildHasher = BuildHasherDefault<MyHasher>;
let hash_map = HashMap::<u32, u32, MyBuildHasher>::default();RunTrait Implementations§
const: unstable · source§impl<H> BuildHasher for BuildHasherDefault<H>where
H: Default + Hasher,
impl<H> BuildHasher for BuildHasherDefault<H>where
H: Default + Hasher,
source§impl<H> Clone for BuildHasherDefault<H>
impl<H> Clone for BuildHasherDefault<H>
source§fn clone(&self) -> BuildHasherDefault<H>
fn clone(&self) -> BuildHasherDefault<H>
Returns a copy of the value. Read more
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from
source. Read more