Struct ahash::AHasher [−][src]
pub struct AHasher { /* fields omitted */ }
Expand description
A Hasher
for hashing an arbitrary stream of bytes.
Instances of AHasher
represent state that is updated while hashing data.
Each method updates the internal state based on the new data provided. Once
all of the data has been provided, the resulting hash can be obtained by calling
finish()
Clone is also provided in case you wish to calculate hashes for two different items that start with the same data.
Implementations
impl AHasher
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impl AHasher
[src]pub fn new_with_keys(key1: u128, key2: u128) -> Self
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pub fn new_with_keys(key1: u128, key2: u128) -> Self
[src]Creates a new hasher keyed to the provided keys.
Normally hashers are created via AHasher::default()
for fixed keys or RandomState::new()
for randomly
generated keys and RandomState::with_seeds(a,b)
for seeds that are set and can be reused. All of these work at
map creation time (and hence don’t have any overhead on a per-item bais).
This method directly creates the hasher instance and performs no transformation on the provided seeds. This may be useful where a HashBuilder is not desired, such as for testing purposes.
Example
use std::hash::Hasher; use ahash::AHasher; let mut hasher = AHasher::new_with_keys(1234, 5678); hasher.write_u32(1989); hasher.write_u8(11); hasher.write_u8(9); hasher.write(b"Huh?"); println!("Hash is {:x}!", hasher.finish());
Trait Implementations
impl Default for AHasher
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impl Default for AHasher
[src]Provides a default Hasher with fixed keys. This is typically used in conjunction with BuildHasherDefault to create AHashers in order to hash the keys of the map.
Generally it is preferable to use RandomState instead, so that different hashmaps will have different keys. However if fixed keys are desireable this may be used instead.
Example
use std::hash::BuildHasherDefault; use ahash::{AHasher, RandomState}; use std::collections::HashMap; let mut map: HashMap<i32, i32, BuildHasherDefault<AHasher>> = HashMap::default(); map.insert(12, 34);
fn default() -> AHasher
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fn default() -> AHasher
[src]Constructs a new AHasher with fixed keys.
If std
is enabled these will be generated upon first invocation.
Otherwise if the compile-time-rng
feature is enabled these will be generated at compile time.
If neither of these features are available, hardcoded constants will be used.
Because the values are fixed, different hashers will all hash elements the same way. This could make hash values predictable, if DOS attacks are a concern. If this behaviour is not required, it may be preferable to use RandomState instead.
Examples
use ahash::AHasher; use std::hash::Hasher; let mut hasher_1 = AHasher::default(); let mut hasher_2 = AHasher::default(); hasher_1.write_u32(1234); hasher_2.write_u32(1234); assert_eq!(hasher_1.finish(), hasher_2.finish());
impl Hasher for AHasher
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impl Hasher for AHasher
[src]Provides Hasher methods to hash all of the primitive types.
fn write_u128(&mut self, i: u128)
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fn write_u128(&mut self, i: u128)
[src]Writes a single u128
into this hasher.
fn write_usize(&mut self, i: usize)
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fn write_usize(&mut self, i: usize)
[src]Writes a single usize
into this hasher.
fn write_i128(&mut self, i: i128)
1.26.0[src]
fn write_i128(&mut self, i: i128)
1.26.0[src]Writes a single i128
into this hasher.
fn write_isize(&mut self, i: isize)
1.3.0[src]
fn write_isize(&mut self, i: isize)
1.3.0[src]Writes a single isize
into this hasher.
Auto Trait Implementations
impl RefUnwindSafe for AHasher
impl Send for AHasher
impl Sync for AHasher
impl Unpin for AHasher
impl UnwindSafe for AHasher
Blanket Implementations
impl<T> BorrowMut<T> for T where
T: ?Sized,
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impl<T> BorrowMut<T> for T where
T: ?Sized,
[src]pub fn borrow_mut(&mut self) -> &mut T
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pub fn borrow_mut(&mut self) -> &mut T
[src]Mutably borrows from an owned value. Read more
impl<T> ToOwned for T where
T: Clone,
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impl<T> ToOwned for T where
T: Clone,
[src]type Owned = T
type Owned = T
The resulting type after obtaining ownership.
pub fn to_owned(&self) -> T
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pub fn to_owned(&self) -> T
[src]Creates owned data from borrowed data, usually by cloning. Read more
pub fn clone_into(&self, target: &mut T)
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pub fn clone_into(&self, target: &mut T)
[src]🔬 This is a nightly-only experimental API. (toowned_clone_into
)
recently added
Uses borrowed data to replace owned data, usually by cloning. Read more