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/Rust

Struct std::hash::BuildHasherDefault

pub struct BuildHasherDefault<H>(_);

The BuildHasherDefault structure is used in scenarios where one has a type that implements Hasher and Default, but needs that type to implement BuildHasher.

This structure is zero-sized and does not need construction.

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

impl<H> Default for BuildHasherDefault<H> [src]

Returns the "default value" for a type. Read more

impl<H> Clone for BuildHasherDefault<H> [src]

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

impl<H> BuildHasher for BuildHasherDefault<H> where H: Default + Hasher [src]

Type of the hasher that will be created.

Creates a new hasher. Read more

impl<H> Debug for BuildHasherDefault<H>
1.9.0
[src]

Formats the value using the given formatter.

© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/hash/struct.BuildHasherDefault.html