Struct wasmer_types::lib::std::hash::BuildHasherDefault 1.7.0[−][src]
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();
Trait Implementations
Returns the “default value” for a type. Read more
Auto Trait Implementations
impl<H> RefUnwindSafe for BuildHasherDefault<H> where
H: RefUnwindSafe,
impl<H> Send for BuildHasherDefault<H> where
H: Send,
impl<H> Sync for BuildHasherDefault<H> where
H: Sync,
impl<H> Unpin for BuildHasherDefault<H> where
H: Unpin,
impl<H> UnwindSafe for BuildHasherDefault<H> where
H: UnwindSafe,
Blanket Implementations
type ArchivedMetadata = ()
type ArchivedMetadata = ()
The archived version of the pointer metadata for this type.
Converts some archived metadata to the pointer metadata for itself.
Mutably borrows from an owned value. Read more
Compare self to key
and return true
if they are equal.