Struct fastbloom::BuilderWithFalsePositiveRate

pub struct BuilderWithFalsePositiveRate<const BLOCK_SIZE_BITS: usize = 512, S = DefaultHasher> { /* private fields */ }

A bloom filter builder with an immutable false positive rate.

This type can be used to construct an instance of BloomFilter via the builder pattern.

Examples

use fastbloom::BloomFilter;

let builder = BloomFilter::with_false_pos(0.01);

Implementations

impl<const BLOCK_SIZE_BITS: usize> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS>

pub fn seed(self, seed: &u128) -> Self

Sets the seed for this builder. The later constructed BloomFilter will use this seed when hashing items.

Examples

use fastbloom::BloomFilter;

let bloom = BloomFilter::with_false_pos(0.001).seed(&1).expected_items(100);

impl<const BLOCK_SIZE_BITS: usize, S: BuildHasher> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

pub fn hasher<H: BuildHasher>( self, hasher: H ) -> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, H>

Sets the hasher for this builder. The later constructed BloomFilter will use this hasher when inserting and checking items.

Examples

use fastbloom::BloomFilter;
use ahash::RandomState;

let bloom = BloomFilter::with_false_pos(0.001).hasher(RandomState::default()).expected_items(100);

pub fn expected_items( self, expected_num_items: usize ) -> BloomFilter<BLOCK_SIZE_BITS, S>

“Consumes” this builder, using the provided expected_num_items to return an empty BloomFilter. The number of hashes and underlying memory is optimized based on expected_num_items to meet the desired false positive rate. More or less than expected_num_items may be inserted into BloomFilter.

Examples

use fastbloom::BloomFilter;

let bloom = BloomFilter::with_false_pos(0.001).expected_items(500);

pub fn items<I: IntoIterator<IntoIter = impl ExactSizeIterator<Item = impl Hash>>>( self, items: I ) -> BloomFilter<BLOCK_SIZE_BITS, S>

“Consumes” this builder and constructs a BloomFilter containing all values in items. Like BuilderWithFalsePositiveRate::expected_items, the number of hashes per item and underlying memory is optimized based on items.len() to meet the desired false positive rate.

Examples

use fastbloom::BloomFilter;

let bloom = BloomFilter::with_false_pos(0.001).items([1, 2, 3]);

impl<const BLOCK_SIZE_BITS: usize, S: BuildHasher> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

pub fn block_size_64(self) -> BuilderWithFalsePositiveRate<64, S>

Set the block size of the bloom filter to 64 bits. The underlying bit vector size will be rounded up to be a multiple of the block size.

Example

use fastbloom::BloomFilter;
let builder = BloomFilter::with_false_pos(0.01).block_size_64();

impl<const BLOCK_SIZE_BITS: usize, S: BuildHasher> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

pub fn block_size_128(self) -> BuilderWithFalsePositiveRate<128, S>

Set the block size of the bloom filter to 128 bits. The underlying bit vector size will be rounded up to be a multiple of the block size.

Example

use fastbloom::BloomFilter;
let builder = BloomFilter::with_false_pos(0.01).block_size_128();

impl<const BLOCK_SIZE_BITS: usize, S: BuildHasher> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

pub fn block_size_256(self) -> BuilderWithFalsePositiveRate<256, S>

Set the block size of the bloom filter to 256 bits. The underlying bit vector size will be rounded up to be a multiple of the block size.

Example

use fastbloom::BloomFilter;
let builder = BloomFilter::with_false_pos(0.01).block_size_256();

impl<const BLOCK_SIZE_BITS: usize, S: BuildHasher> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

pub fn block_size_512(self) -> BuilderWithFalsePositiveRate<512, S>

Set the block size of the bloom filter to 512 bits. The underlying bit vector size will be rounded up to be a multiple of the block size.

Example

use fastbloom::BloomFilter;
let builder = BloomFilter::with_false_pos(0.01).block_size_512();

Trait Implementations

impl<const BLOCK_SIZE_BITS: usize, S: Clone> Clone for BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

fn clone(&self) -> BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<const BLOCK_SIZE_BITS: usize, S: Debug> Debug for BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

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

Formats the value using the given formatter.

impl<const BLOCK_SIZE_BITS: usize, S: BuildHasher> PartialEq for BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<const BLOCK_SIZE_BITS: usize, S: BuildHasher> Eq for BuilderWithFalsePositiveRate<BLOCK_SIZE_BITS, S>