Struct PartitionedMphf 

pub struct PartitionedMphf { /* private fields */ }

A partitioned minimal perfect hash function.

Splits keys into partitions by hash range (Lemire fast-range reduction), builds one PHast MPHF per partition, and routes queries transparently. Global indices are offsets[partition] + inner_mphf.get(key).

Implementations

impl PartitionedMphf

pub fn build_from_vec<K: Hash + Clone + Send + Sync>( keys: Vec<K>, partitioned: bool, ) -> Self

Build a partitioned MPHF from an owned Vec of keys.

If partitioned is false (or there are fewer than AVG_PARTITION_SIZE keys), a single partition is used — equivalent to a monolithic MPHF with zero query overhead.

pub fn build_from_slice<K: Hash + Clone + Send + Sync>( keys: &[K], partitioned: bool, ) -> Self

Build a partitioned MPHF from a slice of keys (clones into Vec).

pub fn get<K: Hash + ?Sized>(&self, key: &K) -> usize

Look up a key and return its global index in [0, num_keys).

For keys NOT in the build set, returns num_keys (out-of-range sentinel). The COMBINE-lab ph fork returns usize::MAX for keys that exhaust all levels without matching, which we map to num_keys.

pub fn num_keys(&self) -> usize

Total number of keys.

pub fn num_partitions(&self) -> u32

Number of partitions.

pub fn write_to<W: Write>(&self, writer: &mut W) -> Result<()>

Serialize to a writer.

pub fn read_from(reader: &mut dyn Read) -> Result<Self>

Deserialize from a reader.

pub fn write_bytes(&self) -> usize

Estimate serialized byte size (for container offset table pre-allocation).