Struct astral::util::hash::NopHasher

pub struct NopHasher { /* private fields */ }

An implementation of Hasher hasher which only accepts values with a size of 8 bytes or an integral value fitting into 8 bytes.

Panics

Panics if values with a size greater than 8 bytes are passed in.

Examples

Usage:

use std::hash::{Hash, Hasher};

use astral::util::hash::NopHasher;

let mut hasher = NopHasher::default();
1234_5678_u32.hash(&mut hasher);
assert_eq!(hasher.finish(), 1234_5678);

Slices and arrays cannot be hashed directly, since their len is also hashed. Hash::hash_slice may be used instead:

use std::hash::{Hash, Hasher};

use astral::util::hash::NopHasher;

let mut hasher = NopHasher::default();
let arr = [0x12_u8, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0];
Hash::hash_slice(&arr, &mut hasher);
assert_eq!(hasher.finish(), 0x1234_5678_9ABC_DEF0_u64.to_be());

Trait Implementations

impl Clone for NopHasher

fn clone(&self) -> NopHasher

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NopHasher

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for NopHasher

fn default() -> NopHasher

Returns the “default value” for a type.

impl Hasher for NopHasher

fn finish(&self) -> u64

Returns the hash value for the values written so far.

fn write(&mut self, bytes: &[u8])

Writes some data into this Hasher.

fn write_u8(&mut self, i: u8)

Writes a single u8 into this hasher.

fn write_u16(&mut self, i: u16)

Writes a single u16 into this hasher.

fn write_u32(&mut self, i: u32)

Writes a single u32 into this hasher.

fn write_usize(&mut self, i: usize)

Writes a single usize into this hasher.

fn write_i8(&mut self, i: i8)

Writes a single i8 into this hasher.

fn write_i16(&mut self, i: i16)

Writes a single i16 into this hasher.

fn write_i32(&mut self, i: i32)

Writes a single i32 into this hasher.

fn write_isize(&mut self, i: isize)

Writes a single isize into this hasher.

fn write_u64(&mut self, i: u64)

Writes a single u64 into this hasher.

fn write_u128(&mut self, i: u128)

Writes a single u128 into this hasher.

fn write_i64(&mut self, i: i64)

Writes a single i64 into this hasher.

fn write_i128(&mut self, i: i128)

Writes a single i128 into this hasher.

fn write_length_prefix(&mut self, len: usize)

🔬This is a nightly-only experimental API. (hasher_prefixfree_extras)

Writes a length prefix into this hasher, as part of being prefix-free.

fn write_str(&mut self, s: &str)

🔬This is a nightly-only experimental API. (hasher_prefixfree_extras)

Writes a single str into this hasher.