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BloomFilter

Struct BloomFilter 

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pub struct BloomFilter { /* private fields */ }
Expand description

Space-efficient probabilistic membership filter.

False negatives are impossible; false positives occur with probability ≤ the configured false_positive_rate when the number of inserted items does not exceed expected_items.

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impl BloomFilter

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pub fn new(expected_items: usize, false_positive_rate: f64) -> Self

Construct a new BloomFilter optimised for expected_items items and the target false_positive_rate (between 0 and 1 exclusive).

Panics if expected_items == 0 or false_positive_rate is outside (0, 1).

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pub fn insert(&mut self, item: &[u8])

Insert item into the filter. After this call contains(item) is guaranteed to return true.

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pub fn contains(&self, item: &[u8]) -> bool

Return true if item may be in the set; false means it definitely is not.

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pub fn estimate_false_positive_rate(&self) -> f64

Estimate the current false-positive probability given the number of items inserted so far.

Formula: (1 - e^(-k * n / m))^k

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pub fn item_count(&self) -> u64

Return the number of items inserted so far.

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pub fn num_bits(&self) -> usize

Return the number of addressable bits in the underlying array.

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pub fn num_hash_functions(&self) -> u8

Return the number of hash functions used per operation.

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impl Clone for BloomFilter

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fn clone(&self) -> BloomFilter

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

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

Performs copy-assignment from source. Read more
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impl Debug for BloomFilter

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

Formats the value using the given formatter. Read more

Auto Trait Implementations§

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.